Agilent 8757D Operating Reference

Operating Reference

Agilent Technologies

8757D Scalar Network Analyzer

Manufacturing Part Number: 08757-90169

Master Set Part Number: 08757-90109

Printed in USA

Print Date: November 2000

Supersedes: March 19 93

© Agilent Technologies, Inc. 1993, 2000

Hewlett-Packard to Agilent Technologies Transition

This manual may contain references to HP or Hewlett-Packard. Please note that
Hewlett-Packard's former test and measurement, semiconductor products and chemical analysis
businesses are now part of Agilent Technologies. To reduce potential confusion, the only
change to product numbers and names has been in the company name prefix: where a product
number/name was HP XXXX the current name/number is now Agilent XXXX. For example,
model number HP8648 is now model number Agilent 8648.

Documentation Warranty

THE MATERIAL CONTAINED IN THIS DOCUMENT IS PROVIDED "AS IS," AND IS
SUBJECT TO BEING CHANGED, WITHOUT NOTICE, IN FUTURE EDITIONS. FUR­THER, TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, AGILENT
DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED WITH REGARD TO
THIS MANUAL AND ANY INFORMATION CONTAINED HEREIN, INCLUDING BUT
NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FIT­NESS FOR A PARTICULAR PURPOSE. AGILENT SHALL NOT BE LIABLE FOR
ERRORS OR FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES IN CONNECTION
WITH THE FURNISHING, USE, OR PERFORMANCE OF THIS DOCUMENT OR ANY
INFORMATION CONTAINED HEREIN. SHOULD AGILENT AND THE USER HAVE A
SEPARATE WRITTEN AGREEMENT WITH WARRANTY TERMS COVERING THE
MATERIAL IN THIS DOCUMENT THAT CONFLICT WITH THESE TERMS, THE WAR­RANTY TERMS IN THE SEPARATE AGREEMENT WILL CONTROL.

DFARS/Restricted Rights Notice

If software is for use in the per formance of a U.S. Government prime contract or
subcontract, Software is delivered and licensed as “Commercial computer software” as
defined in DFAR 252.227-7014 (June 1995), or as a “commercial item” as defined in FAR

2.101(a) or as “Restricted computer sof tware” as defined in FAR 52.227-19 (June 1987) or
any equivalent agency regulation or contract clause. Use, duplication or disclosure of
Software is subject to Agilent Technologies’ standard commercial l icense terms, and
non-DOD Departments and Agencies of the U.S. Government will receive no greater than
Restricted Rights as defined in FAR 52.227-19(c)(1-2) (June 1987) . U.S. Government users
will receive no greater than Limited Rights as defined in FAR 52.227-14 (June 1987) or
DFAR 252.227-7015 (b)(2) (November 1995), as applicable in any technical data.

Printing Copies of Documentation from the Web

To print copies of documentation from the Web, download the PDF file from the Agilent
web site:

•Go to http://www.agilent.com.

• Enter the document’s pa rt number (located on the title page) in the Quick Search box.

• Click GO.

• Click on the hyperlink for the document.

• Click the printer icon located in the tool bar.

Contacting Agilent

This information supersedes all prior HP contact information.

Online assistance: www.agilent.com/find/assist

Americas

Brazil

(tel) ([phone]
(fax) ([phone]

Canada

(tel) 888 447 7378
(fax) 905 282 6495

Mexico

(tel) 1 800 254 2440
(fax) 1 800 254 4222

Asia Pacific and Japan

Australia

(tel) 1 800 225 574
(fax) 1 800 681 776
(fax) 1 800 225 539

Japan (Bench)

(tel) 0120 32 0119
(alt) ([phone]
(fax) 0120 01 2144

Taiwan

(tel) 0800 047 669
(fax) 0800 047 667
(fax) 886 3492 0779

China

(tel) 800 810 0508
(alt) 800 810 0510
(fax) 800 810 0507
(fax) 800 810 0362

Japan (On-Site)

(tel) 0120 802 363
(alt) ([phone]
(fax) ([phone]

Thailand

(tel) 1 800 2758 5822
(alt) ([phone]
(fax) 1 800 656 336

Hong Kong
(tel) 800 933 229
(fax) 800 900 701

Singapore

(tel) 1 800 275 0880
(fax) ([phone]
(fax) ([phone]

Malaysia

(tel) 1800 880 399
(fax) 1800 801 054

Europe

Austria

(tel) 0820 87 44 11*
(fax) 0820 87 44 22

France

(tel) 0825 010 700*
(alt) (+33) (0)1 6453 5623
(fax) 0825 010 701*

Italy

(tel) (+39) (0)2 9260 8484
(fax) (+39) (0)2 9544 1175

Spain

(tel) ([phone]
(alt) ([phone]
(fax) ([phone]

Switzerland (Italian)

(tel) 0800 80 5353 opt. 3*
(alt) (+39) (0)2 9260 8484
(fax) (+41) (0)22 567 5314

(tel) = primary telephone number; (alt) = alternate telephone number; (fax) = FAX number; * = in country number

Belgium

(tel) (+32) (0)2 404 9340
(alt) (+32) (0)2 404 9000
(fax) (+32) (0)2 404 9395

Germany

(tel) 01805 24 6333*
(alt) 01805 24 6330*
(fax) 01805 24 6336*

Luxemburg

(tel) (+32) (0)2 404 9340
(alt) (+32) (0)2 404 9000
(fax) (+32) (0)2 404 9395

Sweden

(tel) 0200 88 22 55*
(alt) (+46) (0)8 5064 8686
(fax) 020 120 2266*

United King dom

(tel) (+44) (0)7004 666666
(alt) (+44) (0)7004 123123
(fax) (+44) (0)7004 444555

Denmark

(tel) ([phone]
(alt) ([phone]
(fax) ([phone]

Ireland

(tel) (+353) (0)1 890 924 204
(alt) (+353) (0)1 890 924 206
(fax)(+353) (0)1 890 924 024

Netherlands

(tel) (+31) (0)20 547 2111
(alt) (+31) (0)20 547 2000
(fax) (+31) (0)20 547 2190

Switzerland (French)

(tel) 0800 80 5353 opt. 2*
(alt) (+33) (0)1 6453 5623
(fax) (+41) (0)22 567 5313

United States

(tel) 800 829 4444
(alt) ([phone]
(fax) 800 829 4433

India

(tel) 1600 112 626
(fax) 1600 112 727
(fax) 1600 113 040

South Korea

(tel) 080 778 0011
(fax) 080 778 0013

Finland

(tel) ([phone]
(fax) (+358) (0) 10 855 2923

Israel

(tel) ([phone]
(fax) ([phone]

Russia

(tel) ([phone]
(alt) ([phone]
(fax) ([phone]

Switzerland (German )

(tel) 0800 80 5353 opt. 1*
(alt) (+49) (0)7031 464 63 33
(fax) (+41) (0)1 272 7373

8/03/04

Operating Reference

Added Benefits of the HP/Agilent 8757D (Revision 5.1 and above)

The 8757D provides all of the same features as the HP/Agilent 8757A and HP/Agilent 8757C,

but also provides the follo wing features:

improved absolute p ower accuracy with Option 002 50 MHz p ower calibrator

compatibility with HP/Agilent 85037A/B precision detectors in addition to all HP/Agilent

scalar detectors and bridges

improved accuracy for mixer measurements from the detector frequency function

Detector Oset:

1. extended amplitude display range with detector osets up to660 dB

2. the ability to measure a detector oset with the power calibrator to compensate for RF

attenuators

3. detector osets are zero ed at preset

four channel keys for easier menu use and access (channel number keys toggle the channels

active and inactive)

four display formats have uncoupled scale factors and reference values:

NNNNNNNNNNN

1.

MEM

NNNNNNNNNNNNNN

2.

MEAS

NNNNNNNNNNNNNNNNNNNNNNNNNNN

3.

MEAS0MEM

and

4. SWR

SWR display is allowed on anychannel

limit lines may be used with anynumber of trace p oints for anychannel

improved measurement sp eed

cursor frequency readout for applications where an HP-IB sweeper is not used (frequencies

are set by lab els

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START FREQ

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

and

STOP FREQ

)

data recalled from disk may b e reformatted or smoothed

Added Benefits of the 8757D (Revision 6.1 and above)

The 8757D (revision 6.0) provides all of the same features as the 8757D (revision 5.1) plus the

following features:

improved measurement sp eed

clock feature (app earance of date and time on hardcopies and disk les)

HP/Agilent 83750 Series source compatibility

interpolated markers

ten available markers

improved frequency accuracy

HP/Agilent 8757D Operating Reference iii

Using this Reference

Use this reference to help you op erate the analyzer locally.For additional information, see the

User's Guide

, also included in this section (Local Operation). The

User's Guide

describes

general measurement setups and includes typical measurement examples.

This document provides the following information:

HP/Agilent 8757D operating features:

front and rear panel features

hardkey op eration

softkey op eration

softkey menu structure maps

operator's check

measurement applications

Finding a

4

Hardkey

5

Description

This document divides the front panel keys (hardkeys) into the functional groups lab eled on

the analyzer front panel.

CHANNEL

FUNCTION

ENTRY

INSTRUMENT STATE

To nd a front panel key description:

1. Locate the key in the index.

2. Turn to the page listed for that key.

W

WWWWWWWWWWWWWWWWWWWWWWWW

Finding a

Softkey

Description

When you press most front panel keys, one or more softkey menus is displayed. To nd a

softkey description:

1. Locate the key in the index.

2. Turn to the page listed for that key.

Softkey descriptions, included with each front panel key description, appear in the order in

which the analyzer displays the softkeys, from the top to the b ottom.

W

WWWWWWWWWWWWWW

MORE

This softkey presents the next menulayer.

W

WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW

PRIOR MENU

This softkey displays the previous menu.

iv HP/Agilent 8757D Operating Reference

Contents

1. FrontPanel Features

CRT/LCD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

HP-IB STATUS . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Detector Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Power Calibrator . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

2. CHANNEL

3. ENTRY Area

4. FUNCTION

4

5

MEAS

4

DISPLAY

| Measurement Menus . . . . . . . . . . . . . . . . . . . . . 4-2

5

| Display Menus . . . . . . . . . . . . . . . . . . . . . . . 4-4

Horizontal Display Resolution . . . . . . . . . . . . . . . . . . . . 4-7

Display Resolution . . . . . . . . . . . . . . . . . . . . . . . . 4-7

Measurement Resolution . . . . . . . . . . . . . . . . . . . . . . 4-7

4

5

SCALE

4

REF

4

CURSOR

| Scale Menus . . . . . . . . . . . . . . . . . . . . . . . . 4-9

5

| Reference Menus . . . . . . . . . . . . . . . . . . . . . . . 4-10

5

| Cursor Menus . . . . . . . . . . . . . . . . . . . . . . . 4-11

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11

Cursor Interaction with Source Markers . . . . . . . . . . . . . . . 4-11

Applications for Analyzer Cursors . . . . . . . . . . . . . . . . . 4-11

Applications for Source Markers . . . . . . . . . . . . . . . . . 4-12

Source Capabilities . . . . . . . . . . . . . . . . . . . . . . . 4-12

4

5

|Average Menu . . . . . . . . . . . . . . . . . . . . . . . . 4-14

AVG

4

5

| Calibration Menus . . . . . . . . . . . . . . . . . . . . . . . 4-15

CAL

Self-Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-21

Autocalibration . . . . . . . . . . . . . . . . . . . . . . . . . . 4-22

Temperature Compensation . . . . . . . . . . . . . . . . . . . . 4-22

4

5

| Special Menus . . . . . . . . . . . . . . . . . . . . . . . . 4-23

SPCL

5. INSTRUMENT STATE

4

SYSTEM

4

LOCAL

5

| System Menus . . . . . . . . . . . . . . . . . . . . . . . 5-2

5

| Local Menu. . . . . . . . . . . . . . . . . . . . . . . . . 5-10

Changing a Default Address . . . . . . . . . . . . . . . . . . . . . 5-10

4

5

|Save Menus . . . . . . . . . . . . . . . . . . . . . . . . . 5-11

SAVE

4

RECALL

4

PRESET

5

| Recall Menus . . . . . . . . . . . . . . . . . . . . . . . 5-17

5

| Preset Key . . . . . . . . . . . . . . . . . . . . . . . . 5-21

Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-21

Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22

Plotter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22

Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22

HP 8757D Operating Reference Contents-1

Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23

Unchanged Analyzer Conditions . . . . . . . . . . . . . . . . . . . 5-23

6. Rear Panel Features

A. Operator's Check

Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . A-1

Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2

B. Softkey Menu Structure Maps

C. Performing an External Calibration

Performing an External Detector Calibration with an HP 85025C . . . . . . C-1

External Detector Measurement Calibration . . . . . . . . . . . . . . C-1

Equipment required: . . . . . . . . . . . . . . . . . . . . . . . . C-1

ACversus DC Measurement Calibration . . . . . . . . . . . . . . . . C-2

Changing a Stored Measurement Calibration . . . . . . . . . . . . . . C-3

Uncalibrated Operation . . . . . . . . . . . . . . . . . . . . . . . C-3

Zeroing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-3

D. Measurement Applications

Mixer Measurements . . . . . . . . . . . . . . . . . . . . . . . . . D-1

Index

Contents-2 HP 8757D Operating Reference

Figures

1-1. The HP 8757D FrontPanel . . . . . . . . . . . . . . . . . . . . . 1-1

1-2. The Analyzer CRT/LCD . . . . . . . . . . . . . . . . . . . . . . . 1-3

1-3. Mode Labels Description . . . . . . . . . . . . . . . . . . . . . . . 1-4

1-4. HP-IB STATUS Indicators . . . . . . . . . . . . . . . . . . . . . . 1-6

1-5. Detector Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

1-6. Power Calibrator . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8

2-1. CHANNEL Keys and Channel Menu . . . . . . . . . . . . . . . . . 2-1

3-1. Knob, STEP Keys and Numeric Keypad . . . . . . . . . . . . . . . . 3-1

4-1. FUNCTION Keys . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

4-2.

4

5

Key and Measurement Menus . . . . . . . . . . . . . . . . . 4-2

5

Key and Display Menus . . . . . . . . . . . . . . . . . . . 4-4

5

Key and Scale Menu . . . . . . . . . . . . . . . . . . . . . 4-9

5

Key and Ref Menu. . . . . . . . . . . . . . . . . . . . . . . 4-10

5

Key and Display Menus . . . . . . . . . . . . . . . . . . . 4-11

5

Key and Average Menu. . . . . . . . . . . . . . . . . . . . . 4-14

5

Key and Calibration Menus . . . . . . . . . . . . . . . . . . . 4-15

5

Key and Special Menus . . . . . . . . . . . . . . . . . . . . 4-23

4-3.

4-4.

4-5.

4-6.

4-7.

4-8.

4-9.

MEAS

4

DISPLAY

4

SCALE

4

REF

4

CURSOR

4

AVG

4

CAL

4

SPCL

5-1. Instrument State Keys . . . . . . . . . . . . . . . . . . . . . . . . 5-1

5-2.

5-3.

5-4.

4

SYSTEM

4

LOCAL

4

SAVE

5

Key and System Menus . . . . . . . . . . . . . . . . . . . 5-2

5

Key and Lo cal Menu . . . . . . . . . . . . . . . . . . . . . 5-10

5

Key and Save Menus . . . . . . . . . . . . . . . . . . . . . 5-11

5-5. Directory of Stored Files . . . . . . . . . . . . . . . . . . . . . . . 5-14

5-6.

5-7.

4

RECALL

4

PRESET

5

Key and Recall Menus . . . . . . . . . . . . . . . . . . . . 5-17

5

Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-21

6-1. The HP 8757D Rear Panel . . . . . . . . . . . . . . . . . . . . . . 6-1

A-1. Operator's Check Equipment Set-up . . . . . . . . . . . . . . . . . . A-2

B-1. HP 8757D Softkey Menu Structure Map . . . . . . . . . . . . . . . . B-2

B-2. HP 8757D Softkey Menu Structure Map . . . . . . . . . . . . . . . . B-3

B-3. HP 8757D Softkey Menu Structure Map . . . . . . . . . . . . . . . . B-4

B-4. HP 8757D Softkey Menu Structure Map . . . . . . . . . . . . . . . . B-5

D-1. Mixer Lab Equipment Set-up . . . . . . . . . . . . . . . . . . . . . D-1

HP 8757D Operating Reference Contents-3

Tables

1-1. Status Symbol Identication . . . . . . . . . . . . . . . . . . . . . 1-4

1-2. Status Line Description . . . . . . . . . . . . . . . . . . . . . . . 1-5

4-1. Minimum Sweep Time Versus Number of Points . . . . . . . . . . . . 4-7

4-2. Measurement Ranges and Resolution . . . . . . . . . . . . . . . . . 4-7

4-3. Default Scale Per Division for Display Modes . . . . . . . . . . . . . . 4-9

5-1. Example Printout for

5-2. Example Printout for

5-3. HP-IB Default Addresses . . . . . . . . . . . . . . . . . . . . . . 5-10

5-4. Source Settings Saved on Disk . . . . . . . . . . . . . . . . . . . . 5-12

D-1. Three Mixer Measurement Cases . . . . . . . . . . . . . . . . . . . D-2

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PRINT DATA

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PRINT MKRS

. . . . . . . . . . . . . . . . . . 5-4

. . . . . . . . . . . . . . . . . . 5-5

Contents-4 HP 8757D Operating Reference

Front Panel Features

1

Figure 1-1. The HP 8757D Front Panel

1CRT/LCD

2CHANNEL

measurementchannels are already displayed, these keys select the active measurement

channel. The analyzer has ve inputs (four inputs on the front panel and one auxiliary

input on the rear panel) but can display up to four measurementchannels.

3FUNCTION

4ENTRY

data.

5INSTRUMENT STATE

that apply to the entire instrument state, not just to a single channel.

6FOURTH DETECTOR INPUT

001 and Option 002 instruments only.

7DETECTOR INPUTS

HP 8757D Operating Reference Front Panel Features 1-1

Shows measurement annotation, softkey labels, data traces, and more.

Displays a measurementchannel and makes that channel active. When

Engages functions such as calibration and averaging.

Includes knob, STEP keys, softkey menus, and numeric keypad for entering

Controls system functions (such as plotting and dening titles)

The fourth detector input is available on the Option

Connect compatible detectors and directional bridges.

8POWER CALIBRATOR (Option 002)

HP 85037 Series detectors.

Calibrates dynamic accuracy characteristics of

9SOFTKEYS

4105

LINE

Present menu functions, and instrument status information.

Controls ACpower to the analyzer.

1-2 Front Panel Features HP 8757D Operating Reference

CRT/LCD

The analyzer displays information in several areas (see Figure 1-2 ).

Figure 1-2. The Analyzer CRT/LCD

1Mode Labels

turned on, this area shows the following:

measurement mode (single input or ratio)

status symbols (indicating active functions, see Table 1-1)

cursor amplitude for active marker (with compatible sweeper)

scale per division

reference level value

The following locations show mode labels:

Left Side of

CRT/LCD

Channel 1 Channel 2

Channel 3 Channel 4

A highlighted box encloses the active channel mode labels.

Figure 1-3 shows each part of the mo de lab els area. F

Right Side of CRT/LCD

or eachchannel

HP 8757D Operating Reference Front Panel Features 1-3

Figure 1-3. Mode Labels Description

Table 1-1. Status Symbol Identification

Status

Symbol

0

M MEASUREMENT-MINUS-MEMORY

MEM MEMORY

A AVERAGING ON

S SMOOTHING ON

3

ADAPTIVE NORMALIZATION ON

U ADAPTIVE NORMALIZATION ON

Activated

Feature

Function Key/

Instrument State Key

4

DISPLAY

4

DISPLAY

4

AVG

4

SPCL

4

SYSTEM

4

SYSTEM

5

5

5

5

5

5

(uncalibrated)

2Pass/Fail Indicators

channel 1 or 2. These indicators display

3Softkey Labels

Shows the pass/fail status based on the limit lines en

only with both channels 3 and 4 o

Dene the softkey functions for the menu shown. A lab el that is

underlined and displayed with greater intensity indicates the engaged active channel

function.

4Title Line

5ActiveEntry Area

preset (

Shows the title that you haveentered using the SYSTEM menu.

4

PRESET

Displays the last entry or HP-IB command function, except for

5

), measurement(

4

MEAS

5

), and display(

NNNNNNNNNNNNNNNNNNNNNNN

DISPLAY

).

tered for

.

6Message Line

7Reference Line Position

Shows messages and warnings to the op erator.

Identies the reference position for eachchannel with the

channel number and a \>" symbol in the left margin of the graticule grid. You can

position reference lines on major graticule lines.

8Data Display Area

Displays up to four measurementchannel data traces.

1-4 Front Panel Features HP 8757D Operating Reference

9Frequency Labels

Displays the start, stop, and cursor (or source active marker)

frequencies. The cursor frequency takes precedence over the active marker frequency.If

you engage alternate sweep, the alternate sweep frequencies also appear.

4105

Status Line

Shows the current status of the analyzer (see Table 1-2 ). Blank entries do

not apply to the current status.

Table 1-2. Status Line Description

AC 401 DETOFS ABCR FRQ ABCRCWMAN SS NON SYSINTF OFF UNCAL ABCR

1

2



3



4



5



6



7

1AC or DC detection mo de

2Number of trace points:

101

201

401

801

1601

3Non-zero detector oset for each detector indicated

4FRQ (ABCR) indicate that the DET FREQ (on/o ) function is ON for the specied

input (A, B, C, R).

5Sweep mode other than standard swept mode:

MAN manual sweep mo de

CW continuous wave (CW) sweep mo de

NON nonstandard sweep mo de

SS step sweep (available in HP 8340, 8360, and 83750 Series sources)

6HP 8757 system interface is o

7Uncalibrated condition for each detector (A, B, C, R) connected. This message occurs

only when you turn autocalibration

o

(in the CAL menu), and an input drifts out of

calibration (for more information see \Self-Calibration" in chapter 4).

HP 8757D Operating Reference Front Panel Features 1-5

HP-IB STATUS

Figure 1-4. HP-IB STATUS Indicators

The HP-IB STATUS indicators ( Figure 1-4) show the current status of the analyzer. The

indicators do not update continuously. Several complete HP-IB operations can take place

without anychange in the displayed status.

Indicator Analyzer Status

R Remote operation

L Listen mode

T Talk mo de

S Service request (SRQ) asserted

Detector Inputs

Maximum Voltages

Input Voltage

1.67V

2.6.5 V

3. +15 V to012.6 V

Output Voltage

4.012.6 V

5. +15 V

1-6 Front Panel Features HP 8757D Operating Reference

Figure 1-5. Detector Inputs

Figure 1-5 shows the analyzer's detector inputs. Each input has identical characteristics and

allows connection of compatible detectors and bridges.

Input A

Input B

Input C

Input R

is typically used to connect a directional bridge for reection measurements.

is typically used to connect a detector for transmission measurements.

(found on Option 001 only) is typically used to measure a fourth parameter, for

example, where a device under test has more than one output.

is typically used as the reference detector input for ratio measuremen

ts.

HP 8757D Operating Reference Front Panel Features 1-7

Power Calibrator

Figure 1-6. Power Calibrator

Figure 1-6 shows the Option 002 power calibrator output connector. Use the power

calibrator (a multi-level 50 MHz reference) to calibrate the dynamic accuracy characteristics

of HP 85037 Series precision detectors, as well as other HP detectors and bridges. See

\Calibration Menus" in chapter 4.

1-8 Front Panel Features HP 8757D Operating Reference

CHANNEL

2

Figure 2-1. CHANNEL Keys and Channel Menu

Figure 2-1 shows the CHANNEL keys. A channel receives the data from the detector inputs

and the analyzer displays it in a format designated by either the preset conditions or by the

conditions you set from the front panel key entry.

If you press a CHANNEL key for an undisplayed measurementchannel, the analyzer will

display the channel and make that channel active. If you press a CHANNEL key for a

displayed measurementchannel, the analyzer will make that channel active. But, if you press

a CHANNEL key for a displayed and active measurementchannel, the analyzer will turn that

channel o.

The analyzer can select data from up to v

auxiliary input on the rear panel) but can only measure up to four inputs at one time. The

analyzer can only have one

channel mo de lab els. Any function you select applies exclusively to the active channel but

measurement data is updated to all channels simultaneously.At instrument preset, the

measurements on channels 1 and 2 are displayed, with channel 1 active.

active

channel at a time. A highlighted b ox encloses the active

e inputs (four inputs on the front panel and one

HP 8757D Operating Reference CHANNEL 2-1

ENTRY Area

3

Figure 3-1. Knob, STEP Keys and Numeric Keypad

The

ENTRY

area consists of the

knob

, the

STEP keys

, and the

numeric keypad

. (See

Figure 3-1.)

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

Use the

knob

to change currentvalues for various functions suchas

4

SCALE

5

and

REF LEVEL

Counter-clockwise rotation decrements the value; clockwise rotation increments the value.

Use the

Use the

Entries require using a terminator of

STEP

keys to increment or decrement the numerical value of a function.

numeric keypad

digits, decimal points, and minus signs for numerical entries.

4

ENT

5or4

dBm/dB

5

(except for

4

SAVE

5

and

4

RECALL

entries).

4

5

terminates unitless entries suchasaveraging factors (non dBm).

ENT

4

dBm/dB

Note

5

terminates numeric keypad entries for functions suchas

45

deletes the last digit entered.

4

SCALE

5

and

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

REF LEVEL

.

5

.

HP 8757D Operating Reference ENTRY Area 3-1

FUNCTION

4

Figure 4-1. FUNCTION Keys

Figure 4-1 shows the FUNCTION keys. Use the eight FUNCTION keys to engage functions

and present softkey menus that generally apply only to the active channel. These functions

include:

measurement modes

display formats

scale factors

reference levels and p ositions

cursor positioning

averaging

calibration

special functions

HP 8757D Operating Reference FUNCTION 4-1

4

MEAS

5

4

MEAS

5

| Measurement Menus

Figure 4-2.

4

MEAS

5

Key and Measurement Menus

The

4

5

MEAS

key presents the measurement menus (see Figure 4-2). You can select the analyzer

to display either a single measurementchannel or a ratio of channels.

For example:

NNNNN

If you select

A

, the analyzer displays the measured value at input A (in dBm).

NNNNNNNNNNN

If you select

A/R

, the analyzer displays the measured value at input A (in dBm)

measured value at input R (in dBm).

Because the values are in dBm, a logarithmic subtraction equals the linear division A/R,

and the result is displayed in dB.

The softkey function you select applies

only

to the active channel.

minus

the

4-2 FUNCTION HP 8757D Operating Reference

4

MEAS

5

Note

The analyzer displays the selected measurement parameter in the mode lab els area next to the

channel number.

When you press

measure input A, and channel 2 measures input B.

In the mode lab els area,Aappears next to

NNNNNNNNNNN

AUX

selects a voltage input from the rear panel ADC IN (+10 to010 V) connector. The

active channel displays this voltage (instead of data from a single or ratio ed detector input).

You can use this function to observe the control voltage input to a voltage controlled device.

The analyzer can measure and display up to four of the veavailable inputs at

one time (four inputs on the front panel and one auxiliary input on the rear

panel).

4

PRESET

5

(the green INSTRUMENT STATE key), channel 1 then presets to

CH1:

andBnext to

CH2:

.

HP 8757D Operating Reference FUNCTION 4-3

4

DISPLAY

5

4

DISPLAY

5

| Display Menus

The

4

DISPLAY

Figure 4-3.

5

key presents the display menu (Figure 4-3), which allows you to control

4

DISPLAY

5

Key and Display Menus

how the analyzer pro cesses and displays measurement data. This menu lets you show the

measurement, the data in the active channel memory, or the dierence b etween the two. It

also lets you enter the measurement (or the measurement-minus-memory) into memory.

This menu also allows you to dene the colors used for analyzer displa

y attributes such as the

grid, the channel measurement traces, and the labels.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

HOLD ON OFF

freezes the active channel measurement data displayed on the analyzer.

NNNNNNNNNNNNNN

MEAS

shows the measurement data of the selected input (or ratio of inputs).

NNNNNNNNNNN

MEM

shows the measurement data previously stored in the memory of that c

engage this function,

MEM

appears in the status symbols section of the mode labels area for

hannel. When you

that channel.

NNNNNNNNNNNNNNNNNNNNNNNNNN

MEAS-MEM

shows the data previously stored in memory subtracted from the current

measurement data (commonly used during calibration to pro duce a normalized trace). When

you engage this function,-Mappears in the status symbols section of the mode labels area for

that channel.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

TRC FMT SWR dB

provides a choice of data formats for reection data as either standing wave

ratio (SWR) or return loss (dB). At preset, the data is in the return loss format.

You may select SWR for ratio ed or normalized measuremen

ts on all channels and with any

number of points.

4-4 FUNCTION HP 8757D Operating Reference

4

DISPLAY

5

Remember

When you press any of these softkeys, the selected function is engaged only for

the active channel, except for display adjustments.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ADJUST DISPLAY

allows you to adjust the menus that display brightness and color.

NNNNNNNNNNNNNNNNNNNNNNN

BRTNESS

lets you change the brightness (intensity) of the display.

BRTNESS:DISPLAY

appears in the active entry area, with the value last entered).

CRT Display:

100% is equivalent to 100 nits (units of luminance), and is the sp ecied

brightness level at shipment. If you wish, use the front panel knob or numeric keypad to

enter a new value. Terminate the entry with the

4

5

key.You can adjust the brightness

ENT

value down or up (although the display quality is not specied above 100%). The maximum

value depends on the individual display. Preset do es not change the brightness level unless

you set the level below a dened minimum. You can change the minimum brightness level

(see the service manual for instructions).

LCD Display:

the entry with the

Use the front panel knob or numeric keypad to enter a new value. Terminate

4

5

key.You can adjust the brightness value between 50% and 100%.

ENT

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DEFAULT COLORS

sets all analyzer display attributes to the factory-dened default colors,

whichwere scientically chosen to maximize your ability to discern the dierence between

the colors, and to comfortably and eectively view the colors. These choices accommo date

most people with color-decient vision, and provide an easy-to-view contrast.

If the default colors do not accommodate special circumstances, y

ou can make additional

adjustments. The most frequent color deciency is the inability to distinguish red, yellow,

and green. You can usually eliminate confusion with these colors b

brightness b etween the colors (see

vary the degree of whiteness of the color (see

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

COLOR BRTNESS

NNNNNNNNNNNNNNNNN

COLOR

). If you need more contrast, you can

). Usually, minor changes x the

y increasing the

problem.

You can also select one of the 7 factory-dened colors a

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

See (

CHAN x COLOR

).

vailable from the color list.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CHAN x COLOR

select the channel (x = 1, 2, 3, or 4) whose attributes (measurement trace,

mode lab els, limit lines, and reference level marker) you wish to adjust.

When you select this softkey, the analyzer displays the factory-dened color list.

NNNNNNNNNNNNNNNNN

WHITE

NNNNNNNNNNNNNNNNN

,

BLACK

NNNNNNNNNNNNNNNNNNNN

,

YELLOW

NNNNNNNNNNNNNN

,

BLUE

NNNNNNNNNNNNNNNNNNNN

,

SALMON

,

NNNNNNNNNNN

RED

, and

NNNNNNNNNNNNNNNNN

GREEN

constitute the factory-dened

color list. You can use any of these colors for any of the eight analyzer display attributes.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MODIFY COLOR

Remember

selects the menu that lets you adjust a selected color.

Because you can adjust the colors of all the analyzer display attributes,

you can adjust the colors such that you cannot see an attribute against the

background (such as red warning lab els against a red background). The

softkey labels, however, remain visible.

HP 8757D Operating Reference FUNCTION 4-5

4

DISPLAY

5

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

COLOR BRTNESS

changes an attribute's color brightness. When you press this softkey,

the CRT displays the existing value set for that attribute. If you wish, use the front

panel knob or numeric keypad to enter a new value for color brightness. As you change

values, the attribute changes on the analyzer display. Press

4

5

to terminate the

ENT

entry.

NNNNNNNNNNNNNNNNN

COLOR

to pure color). Adjust this parameter the same wayas

changes the degree of whiteness of the attribute's color (on a scale from white

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

COLOR BRTNESS

.

NNNNNNNNNNNNNN

TINT

changes the attribute's hue. The continuum of hues on the color wheel range

from red, through green and blue, and back to red. Adjust this parameter the same

wayas

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

COLOR BRTNESS

.

Note

Preset and power on/o do not aect color selection. Color changes and

adjustments remain in eect until you change them in these menus. To return

to a previously dened color, write down the numeric value of the color

brightness, color, and tint, and enter the appropriate value for each parameter.

NNNNNNNNNNNNNN

MORE

displays the continuation of the color adjust selections.

NNNNNNNNNNNNNN

GRID

selects the analyzer display grid so you can mo dify its color from the

factory-dened color list (

NNNNNNNNNNNNNNNNN

WHITE

NNNNNNNNNNNNNNNNN

,

BLACK

NNNNNNNNNNNNNNNNNNNN

,

YELLOW

NNNNNNNNNNNNNN

,

BLUE

NNNNNNNNNNNNNNNNNNNN

,

SALMON

,

NNNNNNNNNNN

RED

, and

NNNNNNNNNNNNNNNNN

GREEN

).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

BACKGROUND

factory-dened color list (

selects the analyzer display background so you can mo dify its color from the

NNNNNNNNNNNNNNNNN

WHITE

NNNNNNNNNNNNNNNNN

,

BLACK

NNNNNNNNNNNNNNNNNNNN

,

YELLOW

NNNNNNNNNNNNNN

,

BLUE

NNNNNNNNNNNNNNNNNNNN

,

SALMON

,

NNNNNNNNNNN

RED

, and

NNNNNNNNNNNNNNNNN

GREEN

).

NNNNNNNNNNNNNNNNNNNNNNN

WARNING

factory-dened color list (

selects the warning messages so you can modify the color from the

NNNNNNNNNNNNNNNNN

WHITE

NNNNNNNNNNNNNNNNN

,

BLACK

NNNNNNNNNNNNNNNNNNNN

,

YELLOW

NNNNNNNNNNNNNN

,

BLUE

NNNNNNNNNNNNNNNNNNNN

,

SALMON

,

NNNNNNNNNNN

RED

, and

NNNNNNNNNNNNNNNNN

GREEN

).

NNNNNNNNNNNNNNNNNNNN

LABELS

the color from the factory-dened color list (

NNNNNNNNNNN

RED

selects softkey labels, status line, frequency lab els, and title so y

NNNNNNNNNNNNNNNNN

, and

GREEN

).

NNNNNNNNNNNNNNNNN

WHITE

NNNNNNNNNNNNNNNNN

,

BLACK

NNNNNNNNNNNNNNNNNNNN

,

YELLOW

ou can mo dify

NNNNNNNNNNNNNN

,

BLUE

NNNNNNNNNNNNNNNNNNNN

,

SALMON

,

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MONOCHROME

sets all of the analyzer display attributes to green. A highlighted b ox

surrounds the active mo de labels, and the analyzer highlights all attributes asso ciated

with the active channel.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MEAS!MEM

you view the data in SWR format). You can also store voltage data (ADC IN) into memory.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MEAS-M!MEM

stores the current measurement data into memory in dB/dBm format (even when

stores the measurement-minus-memory (normalized trace) into memory.You

can use this function only for ratio measurements.

4-6 FUNCTION HP 8757D Operating Reference

4

DISPLAY

Horizontal Display Resolution

Display Resolution

The analyzer's display resolution is dependent on the number of channels that you have

displayed.

1601 data points available with one channel displayed

801 data p oints available with up to twochannels displayed

401 data p oints available with up to four channels displayed

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

Use the

#TRACE POINTS

softkey in the system menutochange the number of trace points.

If adaptive normalization is on, the cal data is linearly interpolated when you increase the

number of trace p oints after a calibration.

The number of data points and number of channels displayed also aects the minimum sweep

time.

Table 4-1. Minimum Sweep Time Versus Number of Points

5

Number of

Minimum Sweep Time (ms)

Points

1 Input 2 Inputs 3 Inputs 4 Inputs

101 40 40 40 40

201 40 40 52 68

401 40 72 104 136

801 80 144 208 272

1601 160 288 N/A N/A

Measurement Resolution

The analyzer stores memory data at the highest resolution regardless of the displa

y resolution,

scale per division, or reference level. Table 4-2 shows the measurement resolution and range

for the various display modes. The display range can exceed the limits shown when detector

osets are applied.

Table 4-2. Measurement Ranges and Resolution

Display

Mode

dBm070 to +20 dBm 0.003 dB

dB

Measurement

Range

0

90 to +90 dBm 0.006 dB

1

Measurement

Resolution

Normalized

2

2

.006 dB

.011 dB

SWR 1.0 to 37.0 See graph below

0

AUX010 to +10 V30.70 mV 1.40 mV

1

Detector oset is not included.

2

0.01 dB for display cursor.

3020 to +20 V for normalized AUX.

HP 8757D Operating Reference FUNCTION 4-7

4

DISPLAY

The analyzer calculates SWR from dB data. SWR resolution varies with the SWR measured:

5

4-8 FUNCTION HP 8757D Operating Reference

4

SCALE

5

4

SCALE

5

| Scale Menus

Figure 4-4.

The

4

5

SCALE

key allo ws you to select the scale p er division for viewing measuremen

can change the scale factor with the knob, STEP k

4

SCALE

5

Key and Scale Menu

eys, or numeric keypad. The resolution

t data. You

is ner when you are using the knob. Table 4-3 lists the possible choices for each display

mode if you are using the step keys. If you use the keypad to enter the scale factor, you must

terminate the entry with either the

4

dBm/dB

5or4

ENT

5

key.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

AUTOSCALE

adjusts the active trace scale and reference level to b est t within the graticule.

Table 4-3. Default Scale Per Division for Display Modes

DisplayMode Scales Per Division Using the Step Keys

dB/dBm 20, 10, 5, 1, 2, 0.5, 0.2, 0.1

SWR 10, 4, 2, 1, 0.4, 0.2, 0.1, 0.04, 0.02 SWR units

AUX (ADC IN) 5, 2.5, 1, 0.5, 0.25, 0.1, 0.05, 0.025V

Note

The analyzer allows you to set the scale factors for MEAS, MEM, and

MEAS-MEM display modes separately. This function permits you to set the

optimum scale factor for each of these displaytypes.

HP 8757D Operating Reference FUNCTION 4-9

4

REF

4

REF

5

5

| Reference Menus

The

Figure 4-5.

4

5

engages the reference level function (Figure 4-5).

REF

4

5

Key and Ref Menu

REF

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

REF LEVEL

by the reference p osition indicator on the left side of the analyzer displa

value of this line and the scale p er division lets y

lets you set the value of the reference level line (the horizontal line indicated

y). Varying the

ou measure any data p oint and view the

measurement data relative to the reference level line value. Use the knob, STEP keys, or

numeric keypad to enter the reference level, and terminate the entry with the

4

5

key.

ENT

4

dBm/dB

NNNNNNNNNNNNNNNNNNNNNNNNNN

REF POSN

with the knob, a step key, or the numeric keypad terminated with

use the numeric keypad to position the reference, entering

bottom graticule and entering

lets you set the position of the reference level line to any of the ma jor graticules

4

dBm/dB

4

5

places the reference on the

0

4

5

places the reference on the top graticule. The c

9

NNNNNNNNNNN

5

or

GHz

.Ifyou

hannel

number and the \>" symbol to the left of the analyzer display graticule show the current

position of eachchannel's reference level line.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

REF STP SIZE

sets the size of the steps used to increment or decrement the reference level

value. You can set the reference step size with the numeric keypad, step keys, or the front

panel knob. Terminate the entry with the

4

dBm/dB

5or4

ENT

5

key.

5

or

4-10 FUNCTION HP 8757D Operating Reference

4

CURSOR

5

4

CURSOR

5

| Cursor Menus

The

4

CURSOR

Figure 4-6.

5

key presents the cursor menu ( Figure 4-6) and engages the cursor (

4

CURSOR

5

Key and Display Menus

r

)on

all channels. You can turn the front panel knob to move the cursor and quickly read the

measured amplitude and frequency value of any data p oint. The analyzer active entry area

shows the amplitude and frequency value of the data point at the active channel cursor

position. The mo de labels area also displa

y the cursor values. The cursor units corresp ond to

the measurement and display mo de selected (such as dB or SWR), with the value resolved to

0.01 dB, 0.001 SWR, or 0.001 V.

Cursor Interaction with Source Markers

With a cursor activated, the analyzer displays the amplitude and frequency information of the

cursor position. If you turn the cursor function o and activate a source marker, the analyzer

will display the amplitude and frequency information of the marker position (assuming the

source is compatible with the HP 8757 system interface).

Although both cursors and markers display amplitude and frequency information, their

intended use is for dierent applications.

Applications for Analyzer Cursors.

Cursors are particularly useful in the following situations:

when you want to measure bandwidth

when you want to measure one point in reference to another point

when you only want to display2 cursors

HP 8757D Operating Reference FUNCTION 4-11

4

CURSOR

5

Applications for Source Markers.

Markers are particularly useful in the following situations:

when you wantto sweep a range designated bytwo markers

when you want to display more than two markers

Source Capabilities.

Sources that are HP-IB compatible can provide the analyzer with

frequency sweep information over the sytem interface. The analyzer displays the conveyed

source information as start, stop, and marker frequency.Ifyour system interface is not

connected, you can set the analyzer frequency lab els so the analyzer will display the correct

start, stop, and marker frequencies. If you engage alternate sweep, the frequency labels area

displays the marker information for both sweeps.

You can activate up to ve markers on an HP 8350B sweep oscillator, or an HP 8340, 8341, or

8360 Series synthesized sweeper. An HP 83750 Series sweeper allows you to activate up to ten

source markers. You activate and move the source markers from the source front panel.

Most HP 8757D compatible sources create a sweep ramp of 0 to +10 volt sweep ramp.

An HP 83750 Series source creates a pulse train that consists of 1second pulses in both

continuous and step sweep mo des.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

r

CURSOR ON OFF

toggles the cursor on or o. When the cursor is on, it appears as

.You

must turn the cursor o to display the marker frequency and amplitude information.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

C

CURSOR 1 ON OFF

toggles the cursor delta function on and o. With the function on, a

1

appears at the previously set cursor position, designating a reference. The analyzer also

displays another cursor that you can set to any frequency within the displayed range, using

the numeric keypad or front panel knob. Then the analyzer displays the value dierence

between the two trace points. When you engage alternate sweep, the frequency labels area

displays the cursor frequencies for both sweeps.

NNNNNNNNNNN

MAX

positions the cursor to the maximum v

currentsweep. The analyzer does not continuously update the cursor p osition to the

maximum p oint. After data is updated, select

alue p oint on the active channel trace for the

NNNNNNNNNNN

MAX

again to relo cate the cursor to the

maximum p oint.

NNNNNNNNNNN

MIN

positions the cursor to the minimum value point on the active channel trace.

NNNNNNNNNNNNNNNNNNNN

SEARCH

the active channel. Use this function with

presents the search menu and lets you search for a sp ecic value in dB or dBm on

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CURSOR

4

ON

to nd a power dierence in dB.

(You cannot use search functions with SWR or AUX modes.) When you select this softkey,

the analyzer displays the search menu and the active entry area shows the previous search

value. Tochange this value, use the knob, STEP keys, or numeric keypad, terminating the

entry with the

4

dBm/dB

5or4

5

key. Then use the search left/right softkeys to locate the

ENT

entered value.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SEARCH VALUE

Press

4

CURSOR

lets you change the searchvalue.

NNNNNNNNNNNNNNNNNNNN

5

,

SEARCH

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

,

SEARCH VALUE

, and enter the value, for example,

4

454dB

5

using

the numeric keypad.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SEARCH LEFT

causes the cursor to move left to the rst position where the searchvalue

exists. When necessary, the analyzer interpolates the p ointbetween two existing values

and calculates the corresponding frequency. If the analyzer cannot nd the v

analyzer displays

WARNING: Cursor Value not found.

. If the search is successful, the

alue, the

4-12 FUNCTION HP 8757D Operating Reference

4

CURSOR

5

analyzer holds the measurement trace as noted by the displayed message

Trace Hold

. By pressing anykey,you can release the trace hold.

Value Found:

In a normalized measurement, the search function nds the n-dB point from the 0 dB

reference line. In cursor4mode, searchvalues are found for the n-dB points from the

cursor reference.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SEARCH RIGHT

works the same as

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SEARCH LEFT

, except that the cursor moves to the

right.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

BANDWIDTH

determines the trace bandwidth at a sp ecied value down from the maximum

trace value. You can set the n-dB value for the bandwidth with the STEP keys or

the numeric keypad; terminate the entry with the

4

dBm/dB

5or4

5

key. The analyzer

ENT

searches automatically for the maximum trace amplitude, then nds the n-dB down

points on both sides and shows the bandwidth in the active entry area.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CSR FMT SWR DB

lets you view the cursor data in SWR when displaying device return loss

in dB. However, if you are displaying the format in SWR, the cursor data will also be in

SWR.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CURSOR!REF LVL

sets the reference level value equal to the cursor reading. The reference

position do es not change, the trace moves to the reference level. By using this softkey and

decreasing the scale factor, you can expand the trace about the cursor for detailed viewing.

4

HP 8757D Operating Reference FUNCTION 4-13

4

AVG

4

AVG

5

5

|Average Menu

The

Figure 4-7.

4

5

function averages a programmable number of sweeps. When you activate averaging

AVG

4

5

Key and Average Menu

AVG

or restart averaging, the analyzer uses an averaging factor of one on the rst sweep, twoon

the second sweep, four on the third and fourth sw

eep, and increasing powers of twoupto

the desired averaging factor. This technique removes noise from calibration or measurement

traces. The analyzer performs averaging on logarithmic data. When you engage SWR format,

the analyzer p erforms the SWR conversion on the averaged data.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

AVG ON OFF

toggles the averaging function for the activechannel on and o. The active

entry area displays the averaging factor. The mode labels area displays the status symbol

for anychannel with averaging turned on.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

RESTART AVERAGE

clears the averaged data and starts the averaging pro cess to compute

another set of averaged measurement data.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

AVG FACTOR

knob, STEP keys, or numeric keypad. Terminate the entry with the

lets you select the averaging factor (shown in the active entry area) using the

4

5

key.At preset

ENT

and power on, the analyzer defaults to an averaging factor of 8. You can set the averaging

factor to 1, 2, 4, 8, 16, 32, 64, 128, or 256.

A

4-14 FUNCTION HP 8757D Operating Reference

4

CAL

5

| Calibration Menus

4

CAL

5

Figure 4-8.

HP 8757D Operating Reference FUNCTION 4-15

4

5

Key and Calibration Menus

CAL

4

5

CAL

The

4

5

key presents the calibration menus. The softkeys in this menu allowyou to do the

CAL

following activities:

perform and store calibrations

perform detector zero calibrations

set detector osets

turn on automatic internal calibration

You can p erform a calibration without changing the analyzer's display mo de. The analyzer

measures the calibration standards, stores the data at the highest resolution, and returns the

displaymodeyou previously set.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SHORT/OPEN

prompts you through a short/open calibration. The analyzer stores this

calibration in memory in dB/dBm format. When you select this softkey, the analyzer

displays

CONNECT SHORT

...

STORE WHEN READY

, turns averaging o, and presents a second

menulayer.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STORE SHORT

test port, and select this softkey. The analyzer displays

READY

, turns averaging o, and presents a third menulayer.

measures the short circuit resp onse. Connect the short to the bridge

CONNECT OPEN

...

STORE WHEN

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STORE OPEN

bridge test port, and select this softkey

calibration data, stores it in the active c

calibration menu. The analyzer displays

measures the op en circuit resp onse. Connect the open circuit to the

. The analyzer averages the op en and short

hannel memory, and displays the rst

SHORT/OPEN CAL SAVED IN CH1 MEM

(the

indicated channel depends on the active channel).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

AVERAGE ON OFF

when you select averaging in the averaging menu). When you press

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STORE SHORT

toggles averaging on and o (the same averaging function engaged

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SHORT/OPEN

or

, the analyzer turns averaging o. Therefore, if you want the calibration

to be averaged, select averaging on.

The averaging factor does not change from the value you previously set in the

averaging menu. If you wish to change the averaging factor, you must return to the

averaging menu.

NNNNNNNNNNNNNN

THRU

prompts you to make a thru calibration. The analyzer stores this calibration in

dB/dBm format. When you select this softkey, the analyzer displays

STORE WHEN READY

, turns averaging o, and presents a second menulayer.

CONNECT THRU

...

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STORE THRU

measures the thru resp onse. Connect the thru in place of the device

under test and select this softkey. The analyzer displays:

THRU SAVED IN CH1 MEM

If the analyzer is not in measurement-minus-memory mode, the analyzer displays

Normalized Meas

, turns averaging o, and presents the rst calibration menu.

...

select [DISPLAY] [MEAS-MEM].

Press these keys to normalize

For

the measurement.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

AVERAGE ON OFF

when you select averaging in the averaging menu). When you press

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STORE THRU

toggles averaging on and o (the same averaging function engaged

NNNNNNNNNNNNNN

THRU

or

, the analyzer turns averaging o. Therefore, if you want the stored

calibration to b e averaged, select averaging on.

4-16 FUNCTION HP 8757D Operating Reference

4

CAL

The averaging factor does not change from the last value set in the averaging menu. If

you wish to change the averaging factor, you must return to the averaging menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MEAS!MEM

stores the current measured data into memory in dB/dBm format (even if

you view the data in SWR format).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MEAS-M!MEM

stores the measurement-minus-memory (normalized trace) into memory.

You can use this function only for ratio measurements.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DC DET ZERO

in the detector, and establishing the noise o or with no RF signal applied. If your source

is connected over a system interface, pressing

Otherwise, the analyzer presents the

allows you to zero a DC detector, eliminating small DC voltages present

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

NNNNNNNNNNNNNN

CONT

DC DET ZERO

key.

presents another menu.

5

Remember

Periodic zeroing is recommended for DC mode measurements. Zeroing of the

detector is most important for lower level measurements.

This softkey appears in the calibration menu only when you connect an AC/DC detector

or bridge to a detector input.

Zero a DC detector when you rst connect it to the analyzer,

before

calibration, and

whenever signicant temperature changes o ccur.

NNNNNNNNNNNNNNNNNNNN

MANUAL

method of zeroing when a small RF signal is presen

lets you manually remove the RF signal from the detectors. Use this

t in the device under test (suchas

ampliers, mixers, and oscillators).

Note

Before pressing

4

CONT

5

, disconnect your DC detector from any RF signal, then

select the manual method of zeroing.

NNNNNNNNNNNNNN

CONT

nulls any signal present at the detector input. The previous menu returns.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

COARSE ZERO

appears in this menu only if you connect an HP 85025C detector adapter

to the analyzer. See Appendix C \Performing an External Calibration" in this manual,

or refer to the HP 85025C detector adapter manual for instructions on this pro cedure.

(This procedure, written for an HP 8757A, applies also to the HP 8757D.)

NNNNNNNNNNNNNNNNNNNNNNN

AUTOZRO

detector zero. Use this metho d of zeroing in the follo

turns o the RF signal from the source and automatically performs the DC

wing situations:

when your source is connected to the analyzer through the 8757 system in

terface bus

when your test device is NOT an active device; that is, an amplier, mixer, or

oscillator)

You can perform an autozero at any time, even with the repeat autozero function

engaged. This softkey app ears in this menu only if you connect a compatible source to

the analyzer through the 8757 system interface.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

REPT AZ ON OFF

toggles a p eriodic autozero on and o. The analyzer is factory-set to an

interval of 5 minutes.

HP 8757D Operating Reference FUNCTION 4-17

4

5

CAL

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

REPT AZ TIMER

keypad to set intervals from 1 to 60 minutes (terminate the entry with the

lets you change the interval between autozero rep eats. Use the numeric

4

ENT

The interval do es not change at preset or power on.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

COARSE ZERO

allows you to adjust the coarse zero for a minimum signal on the analyzer.

See Appendix C \Performing an External Calibration" in this manual, or refer to the

HP 85025C detector adapter manual for instructions on this procedure. (This pro cedure,

written for an HP 8757A, applies also to the HP 8757D.)

This softkey appears in this menu only if you connect an HP 85025C detector adapter to

the analyzer.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CONFIG SYSTEM

forces the computation on the internal calibration tables for all detector

inputs shown on the analyzer display. See \Self-Calibration" in this section for more

information.

NNNNNNNNNNNNNN

MORE

Presents another menu that continues the calibration menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DET OFFSET

lets you set an oset value in dB for each detector. For example, the

dierence between the power reading of an analyzer input and the p ower meter reading,

or the value of an attenuator used with a detector.

NNNNNNNNNNNNNNNNN

DET A

NNNNNNNNNNNNNNNNN

,

DET B

NNNNNNNNNNNNNNNNN

,

DET C

, and

NNNNNNNNNNNNNNNNN

DET R

let you select the detector to set an oset value.

The active entry area displays the current oset value for that detector. Use the step

keys, knob, or numeric keypad to change the oset, and terminate the entry with the

4

dBm/dB

5or4

5

key. The allo wable range of entry values is +60 to060 dB. The

ENT

analyzer correctly displays the data in dBm, including the oset for absolute p o

measurements, or dB for ratio measurements.

5

key).

wer

A detector oset, valid during both calibration and measurement, remains in eect

until you change it. An oset aects the detector

input

. Therefore, the oset applies

to any measurement made on that input regardless of whichchannel selects the

measurement. When you press

4

PRESET

5

, the analyzer resets all detector oset values to

zero. But, if you cycle the instrumentpower, the detector oset values are not aected.

Osets are stored in the SAVE/RECALL registers.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MEASURE DET OFS

appears when option 002 has b een installed in your analyzer. This

key allows you to measure a detector oset using the 50 MHz power calibrator. The

oset may be measured at any level from +20 dBm to050 dBm. This oset may then

be stored as a detector oset, which is applied during all measurements made with this

detector.

A message app ears on the analyzer :

SELECT DETECTOR FOR DET OFFSET MEASUREMENT

A:ACnDC OFS B:ACnDC R:ACnDC

This message shows that you can select an input for measuring an oset for that

detector. The message displays that input A has an oset entered for it, and that B

and C do not. Also, that AC/DC type detectors (the 85025 or 85037 Series detectors)

are connected to inputs A, B, and R.

NNNNNNNNNNNNNNNNN

DET A

NNNNNNNNNNNNNNNNN

,

DET B

NNNNNNNNNNNNNNNNN

,

DET C

NNNNNNNNNNNNNNNNN

,

DET R

lets you select the detector input for the oset

measurement. Connect the detector and attenuator (if used) between the detector

input and the calibrator.

4-18 FUNCTION HP 8757D Operating Reference

4

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START MEAS

may set the test power for the detector oset when the

starts the detector oset measurement and displays the results. You

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START MEAS

menuis

displayed. The calibrator p ower level used in the measurement is displayed as:

CALIBRATOR POWER

+0 dBm

It is recommended that a calibrator power level be set near the power at which the

detector is being used.

The analyzer p erforms the measurement in the currently selected detection mode,

AC or DC.

If you had a 6 dB attenuator connected to the detector input, you would wantto

measure the actual attenuation. The result display might read:

Det Offset=6.230 dB

Calibrator Pwr= 0 dBm Measured Pwr=06.230 dBm

This means that the calibrator applied 0 dBm to the detector/attenuator and the

HP 8757D measured this power as06.230 dBm. The absolute power measured

depends on the pad attenuation and factors such as temperature drift in the

detector, detector RF connector wear, and inherent accuracy limitations in the

detector.

CAL

5

If an error message is displayed during this process, refer to \In Case of Diculty" in

the Error Messages section.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ABORT CAL

aborts the measurement just started.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STORE OFFSET

stores the measured detector oset that will be used later to

remove this oset error from measurements.

Note

You maywant to connect an attenuator to the input of the detector when y

are making measurements on a high power amplier. For example, to reduce

the RF p ower level below the detector maximum operating power level, or to

reduce the power applied to the detector so harmonics in the test signal cause

less power error in the measurement.

NNNNNNNNNNNNNNNNNNNNNNNNNN

The

DET FREQ

softkey appears when you connect an HP 85037A/B detector to the

analyzer. An HP 85037A/B detector assembly includes an EEPROM that contains

correction constants for that particular detector op eration over a range of frequencies.

The correction constants provide the analyzer with an accurate detector frequency

response. By pressing

NNNNNNNNNNNNNNNNNNNNNNNNNN

DET FREQ

,you can set the start and stop frequencies to apply the

detector frequency resp onse correction for the particular measurement range.

This function could be helpful in a mixer measurement where the frequency you want the

detector to measure is dierent from the source frequency. Refer to \App endix D Mixer

Measurements" for examples of mixer measurements.

ou

HP 8757D Operating Reference FUNCTION 4-19

4

CAL

5

NNNNNNNNNNNNNNNNNNNNNNNNNN

Note

The frequency range you set after pressing

DET FREQ

aects both sweeps

when the analyzer is in the alternate sweep mode. If you set the detector

frequencies with channel 1 or 3 active, then the frequencies apply when

channel 1 and 3 are swept. Likewise, if you set the detector frequencies with

channel 2 or 4 active, the frequencies apply when channel 2 and 4 are swept.

However, you can set unique detector frequency sweep values for dierent

measurementchannels. For example:

Start = 1GHz, Stop = 11 GHz for the sweep on channels 1 and 3

Start = 3GHz, Stop = 13 GHz for the sweep on channels 2 and 4

NNNNNNNNNNNNNNNNN

DET A

NNNNNNNNNNNNNNNNN

,

DET B

NNNNNNNNNNNNNNNNN

,

DET C

NNNNNNNNNNNNNNNNN

,

DET R

lets you select the detector for the entry of start and stop

frequencies.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START FREQ

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

and

STOP FREQ

allow the start and stop frequencies to b e entered.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DET FREQ ON/OFF

activated, otherwise the analyzer will use the sw

The analyzer can display the current detector frequency settings if you enter the

NNNNNNNNNNNNNN

MORE

NNNNNNNNNNNNNNNNNNNNNNNNNN

DET FREQ

,

NNNNNNNNNNNNNNNNN

DET A

must

be turned on for the start and stop frequencies to b e

eeper's start/stop frequencies.

menus (assuming that you selected detector A).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

POWER CAL

presents the power calibration menu. Connect the detector to be calibrated to

POWER CAL OUT.

NNNNNNNNNNNNNNNNN

DET A

NNNNNNNNNNNNNNNNN

,

DET B

NNNNNNNNNNNNNNNNN

,

DET C

NNNNNNNNNNNNNNNNN

,

DET R

lets you select the detector for the p ower cal.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START CAL

starts the calibration. As the calibration pro ceeds, the analyzer displa

the power level being measured. When the calibration is complete, the analyzer

displays the measured range for each detector input.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ABORT CAL

This key allows the user to prematurely stop a p o

wer calibration once it

has been started. For example, when you started the calibration before connecting

the detector.

4

CAL

5

,

ys

By disconnecting a detector from the HP 8757D's input, you remove the calibration.

When you reconnect the detector to the input, the analyzer uses the correction

constants stored in the detector.

Note

To obtain the best accuracy, and to meet the \corrected" dynamic accuracy

specications, each detector must b e characterized on the HP 8757D input

where it will b e used. The characterization routine simultaneously corrects

both AC

and

DC measurements. This routine is also useful as an operator's

check to ensure the detector is op erating correctly. Only the HP 8757D with

an option 002 power calibrator has this capability.

While only specied for the HP 85037 precision detector, the p ower calibrator

also functions with and typically improves the accuracy of the HP 85025,

11664 detectors, HP 85025C external detector, and the HP 85027 bridge. This

process improves the 50 MHz dynamic accuracy to the same accuracy as an

HP 85037 sp ecication.

4-20 FUNCTION HP 8757D Operating Reference

4

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

AUTOCAL ON OFF

gives you control over the automatic regeneration of the internal

calibration tables for the detector inputs. Selecting this softkey toggles auto calibration on

and o. See \Self-Calibration" for more details.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

TEMPCMP ON OFF

gives you control over the analyzer's continuous temperature

compensation. Selecting this softkey toggles temperature compensation on and o. See

\Self-Calibration" for more details.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

EXT DET CAL

appears only if you connect an HP 85025C detector adapter to the analyzer.

Use this function to calibrate the amplitude resp onse for a Schottky dio de detector.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DET PWR CAL

activates a calibration sequence that consists of providing the analyzer

with two known p ower levels. Once you perform a calibration with a detector, the

analyzer retains the calibration.

NNNNNNNNNNNNNNNNN

DET A

NNNNNNNNNNNNNNNNN

,

DET B

NNNNNNNNNNNNNNNNN

,

DET C

NNNNNNNNNNNNNNNNN

,

DET R

lets you select the input for the connected detectors.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CAL VALUE

allows you to enter an HP 85025C detector calibration value on any analyzer

input. See appendix C \Performing an External Detector Calibration" or the HP 85025C

manual for instructions on this procedure (although written for an HP 8757A, it applies

also to an HP 8757D).

NNNNNNNNNNNNNNNNN

DET A

NNNNNNNNNNNNNNNNN

,

DET B

NNNNNNNNNNNNNNNNN

,

DET C

NNNNNNNNNNNNNNNNN

,

DET R

lets you select the detector.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

RESET CAL VALUE

allows you to reset the cal value to factory-set default value.

CAL

5

Self-Calibration

The calibration menu softkeys

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CONFIG SYSTEM

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

,

AUTOCAL ON OFF

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

, and

TEMPCMP ON OFF

relate to the analyzer's internal calibration. With both autocalibration and temp erature

compensation on, the analyzer performs all in

ternal calibration automatically, making it

transparent to the user. The analyzer automatically maintains absolute and dynamic power

accuracy for each detector input using two independent digital correction processes:

1. autocalibration | a regeneration of the in

ternal calibration tables whenever:

you change the accessory conguration

a signicantchange in temperature occurs (approximately 5C)

2. temperature compensation | a continuous comp ensation for small changes in temperature

You can control b oth of these correction pro cesses in the second calibration menu. At preset

or power-on, both autocalibration and temperature compensation are on, and the analyzer

performs all internal calibrations automatically.

HP 8757D Operating Reference FUNCTION 4-21

4

5

CAL

Autocalibration

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

When you turn auto calibration on by selecting

AUTOCAL ON

, the analyzer automatically

updates the internal calibration tables. Use auto calibration for most applications. The

analyzer may update its internal calibrations tables under any of the follo wing conditions:

With autocalibration onoro:

at instrument preset, power-on, or recall instrument state

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CONFIG SYSTEM

softkey selected

Only with auto calibration on:

detector or bridge conguration changed

large temperature change

at a xed 5-minute interval

To regenerate the calibration tables, the analyzer determines the following for each detector

input:

detector or bridge type (AC only or AC/DC)

detector or bridge p ower versus voltage characteristics

temperature of the detector (AC/DC accessories only) and the log amplier

Using these readings, the analyzer automatically computes the internal calibration tables and

the analyzer displays

CONFIG SYSTEM COMPLETED

. Depending on the conguration, the table

regeneration pro cess can take a few seconds.

In a thermally stable environment (temperature drift less than 5



C), thermal drift in the

log ampliers is minimal. The detectors, however, may be exposed to signicantchanges in

temperature. Autocalibration automatically compensates for signican

t temperature changes.

Temperature Compensation

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

When you turn temp erature compensation on

temperature comp ensation to the data. This corrects the measuremen

TEMPCMP ON

, the analyzer performs continuous

t data for small drifts in

temperature without the need to recompute the calibration tables.

Always use temperature compensation when you make measurements (this function turns on

at preset and power-on). Turn o temp erature compensation

only

when diagnosing a p ossible

problem with the analyzer or its detectors.

4-22 FUNCTION HP 8757D Operating Reference

4

SPCL

5

| Special Menus

4

SPCL

5

Figure 4-9.

4

5

Key and Special Menus

SPCL

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SMOOTH ON OFF

toggles the smo othing function (video ltering) on and o. Smoothing

calculates a moving average of the active channel data. The aperture of the moving average is

a percent of the sweep span, not greater than 20%.

Smoothing diers from averaging in that smo othing computes each data point based on one

sweep, on the average of data points on b oth sides of that data poin

t in the currentsweep,

while averaging computes each data point based on the average value of each point during

several sweeps. The mo de labels status symbols area displays an \S" for anychannel with

smoothing activated. Preset turns smoothing o for all channels.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SMOOTH APERT

lets you change the value of the smoothing aperture. The aperture defaults to

5% at preset. Use the knob, STEP keys, or numeric keypad to change the smo othing aperture

value. Enter anyvalue from 0.1 through 20%.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ENTER LIM LNS

presents the rst of two limit lines menus. Using these softkeys, you can

dene limit lines for channel 1 and for channel 2. The limit lines consist of upper and

lower limits for a frequency or a band of frequencies. You can also choose just the upper

or the lower limit. After you activate the limit lines, the measurement data is compared

to the displayed limit lines. The analyzer displays

FAIL

below the mo de lab els area for an

out-of-limit condition. You can choose from three types of limit lines:

point

at

slope

HP 8757D Operating Reference FUNCTION 4-23

4

5

SPCL

A limit line can contain up to 12 segments; each segment can b e any one of the three types.

Segments entered from the front panel are numbered sequentially; those entered through

HP-IB can be entered randomly. The analyzer prompts you for frequency, upper, and lower

limits. Use the numeric keypad to enter the frequency, terminating the entry with the

appropriate softkey:

and lower limits, terminating the entry with the

either an upper or lower limit, press

only

in save/recall registers 1 through 4. You can enter limits in dB, dBm, V (in AUX mo de),

NNNNNNNN

x1

,

NNNNNNNN

Hz

NNNNNNNNNNN

,

kHz

NNNNNNNNNNN

,

MHz

4

NNNNNNNNNNN

,

dBm/dB

GHz

. Use the numeric keypad to enter the upp er

5or4

4

dBm/dB

ENT

5or4

5

at the prompt. You can store limit lines

5

key.Ifyou do not want

ENT

or SWR, depending on the display format. In SWR mode, however, you cannot save the limits

in trace memory.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

POINT LIMIT

lets you dene a limit for a single frequency point.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

FLAT LIMIT

lets you dene a at limit (a constantvalue between two frequency points).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SLOPE LIMIT

lets you dene a sloped limit between two frequency points (linear with

frequency).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

EDIT SEGMENT

lets you redene an existing limit line segment. When you select this

softkey, the analyzer prompts you for the number of the segmentyou wish to change. Use

the numeric keypad to enter the segmentnumber, then press

4

5

. The analyzer deletes

ENT

the entire segment. Re-enter the segment. First choose the limit type from the softkeys.

The analyzer then prompts you to enter frequencies and limit values.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE SEGMENT

lets you delete an entire limit line segment. The analyzer prompts you for

the segmentnumber to delete. Use the numeric keypad to enter the segmentnumber and

terminate the entry with the

4

ENT

5

key.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE ALL LNS

lets you delete all existing limit lines for that c

hannel.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

UPR LIM!MEM

places the upper limit line into memory.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

LWR LIM!MEM

places the lower limit line into memory.

When you put either the upper or lower limit line into memory, the active channel

memory is initialized with a 0 dB (or 0 dBm) reference level. The limits are then up dated

in memory in the order you entered the segments. (For overlapping limits, the last entry

overwrites anyoverlap of the previous entry, and p oints with no limit data entered as 0

dB or 0 dBm.) You cannot use the limit-line-to-memory functions with SWR display

mode.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT ENTRIES

sends the limit line frequency and amplitude values to the plotter (in

tabular format).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PRINT ENTRIES

sends the limit line frequency and amplitude values to the printer (in

tabular form).

NNNNNNNNNNNNNN

DONE

terminates limit line data entry for the active channel. It also returns the special

functions menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

LIM LINS ON OFF

limit lines on, each limit line segment becomes visible on the analyzer as y

turn limit lines on, even without entering limit lines. In this case, the analyzer displa

toggles the limit lines on and o for the active channel. When you turn

ou enter it. You can

ys

PASS

for any measurement data.

4-24 FUNCTION HP 8757D Operating Reference

INSTRUMENT STATE

5

Figure 5-1. Instrument State Keys

Use the INSTRUMENT STATE keys (Figure 5-1) to control system functions that are not

channel-specic but apply to the entire instrument state.

HP 8757D Operating Reference INSTRUMENT STATE 5-1

4

SYSTEM

5

4

SYSTEM

5

| System Menus

Figure 5-2.

The

4

SYSTEM

apply to the entire instrument state (such as plotting, printing, AC and DC detection mo de,

number of trace points, clo ck, and service).

5-2 INSTRUMENT STATE HP 8757D Operating Reference

5

key presents the system menus, providing a variety of softkey functions that

4

SYSTEM

5

Key and System Menus

4

SYSTEM

NNNNNNNNNNNNN

N

PLOT

presents the rst of four plot menus that allow you to custom-dene and initiate plots

on a plotter on the HP 8757 system interface.

When you select a plot softkey, the analyzer freezes the displayed measurement and sends

the data through a buer.

Once the data is at the buer, the analyzer can continue making measurements while the

plotter makes a hardcopy.

The analyzer expects to nd the plotter at HP-IB address 5, unless you set a dierent

address (see

the 8757 SYSTEM INTERFACE, the analyzer displays

problem and press

4

LOCAL

5

). If you set the plotter address incorrectly, or do not connect it to

NNNNNNNNNNNNNN

PLOT

PLOTTER NOT AVAIL

again to start generating the hardcopy.

. Correct the

5

If you do not load any paper, the analyzer displays

problem and press

NNNNNNNNNNNNNN

PLOT

again to start generating the hardcopy.

PLOTTER NOT READY

. Correct the

NNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT ALL

causes the plotter to draw the grid, lab els, trace data, cursor, markers, title,

date, time, and (when turned on) limit lines and pass/fail indicators. Any message

displayed in the activeentry area also plots. (Press

4

ENT OFF

5

before plotting if you do not

want the message to appear.) Plots do not include status line information.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT CUSTOM

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

the

DEFINE CUSTOM

causes the plotter to draw a plot using only the attributes specied with

softkey in this menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT TRACES

draws the trace data for all the channels turned on. The traces include

cursors, cursor deltas, and markers. And if the functions are turned on, the traces also

include limit lines, pass/fail indicators, and a date/time stamp.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT LABELS

draws the mode labels, reference line position lab els, and frequency labels

(when turned on).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT GRID

draws the horizontal and vertical graticule lines.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DEFINE CUSTOM

to include in a custom-dened plot format. The format you dene is reected in the

hardcopy when you press

lets you specify which plot attribute or combination of attributes

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT CUSTOM

. The analyzer highlights the softkey lab els for

the attributes you select to plot.

NNNNNNNNNNNNNNNNNNNN

TRACES

(traces 1-4). Each trace softkey toggles on and o. Y

that are turned on (

lets you specify the trace or traces that the plotter draws on the hardcopy

NNNNNNNNNNNNNNNNNNNNNNN

TRACE 1

NNNNNNNNNNNNNNNNNNNNNNN

,

TRACE 2

NNNNNNNNNNNNNNNNNNNNNNN

,

TRACE 3

ou can only plot traces of channels

NNNNNNNNNNNNNNNNNNNNNNN

,

TRACE 4

).

NNNNNNNNNNNNNN

GRID

includes the horizontal and vertical graticule lines in the custom plot format.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MODE LABELS

includes the mo de labels in the custom plot format.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

FREQ LABELS

(unless you turn them o by pressing

includes the frequency lab el information in the custom plot format

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

LABELS OFF

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

or

FRQ LBL OFF

). The lab el

information includes the sweep frequencies and cursor frequency.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SCALE TO P1P2

plotter's P1 position, and the upper righ

expands the plot to place the lower left corner of the grid at the

t corner of the grid at the plotter's P2

position.

HP 8757D Operating Reference INSTRUMENT STATE 5-3

4

SYSTEM

5

NNNNNNNNNNNNNN

DONE

terminates the custom plot format denition and displays the prior plot menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ABORT PLOT

terminates the plotting of a hardcopy. The plotting do es not stop

immediately; it stops after the buer empties.

NNNNNNNNNNNNNNNNN

PRINT

presents menus that allow you to select printing options.

When you select a print softkey, the analyzer freezes the displayed measurement and sends

the data through a buer. Once the data is at the buer, the analyzer can continue making

measurements while the printer generates a hardcopy.

The analyzer expects to nd the printer at HP-IB address 5, unless you set a dierent

address (see

to the 8757 SYSTEM INTERFACE, the analyzer displays

4

LOCAL

5

). If you set the address of the printer incorrectly, or do not connect it

PRINTER NOT AVAIL

. Correct the

problem and then select the print softkey again to begin printing.

If you connect the printer correctly but do not load any paper the analyzer displays

PRINTER NOT READY

. Correct the problem and then select the print softkey again to begin

printing.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

GRAPH MONO

causes the mono color prin

markers, date, time, and title. Messages in the active en

ter to draw the grid, lab els, trace data, cursors,

try area and most softkeys are

not included.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

GRAPH COLOR

cursors, markers, date, time, and title. Messages in the active en

The printer prints with a default set of colors that appro

causes the color (HP PaintJet) printer to draw the grid, labels, trace data,

try area are not included.

ximate the analyzer default

colors with white and black reversed. You cannot change the xed printer default colors.

Both mono and color prints include limit lines and pass/fail indicators.

Graphics written to the analyzer display through the HP-IB are not drawn by the

printer. You can access the printer with passthrough commands (described in \Remote

Operation").

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PRINT DATA

causes the printer to list all data in tabular form ( T

able 5-1).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

Table 5-1. Example Printout for

PRINT DATA

Frequency Chan. 1 Chan. 2

No. (Hz) (dBm) (dBm)

0 1E+07

1 2.4975E+07

2 3.995E+07

3 5.492E+07

4 6.99E+07

5 8.487501E+07

6 9.985003E+07

7 1.14825E+08

8 1.298E+08

9 1.44775E+08

10 1.5975E+08

11 1.74725E+08

12 1.897E+08

13 1.046751E+08

14 2.1965E+08

0

3.391

0

3.187

0

3.127

0

3.141

0

3.176

0

3.215

0

3.248

0

3.248

0

3.196

0

3.122

0

3.058

0

2.998

0

2.970

0

3.006

0

3.039

0

57.017

0

55.555

0

53.998

0

59.741

0

56.984

0

54.775

0

59.370

0

54.759

0

55.099

0

57.909

0

58.939

0

54.855

0

53.866

0

55.844

0

59.211

5-4 INSTRUMENT STATE HP 8757D Operating Reference

4

SYSTEM

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PRINT MKRS

signals the printer to generate a listing of the frequency and amplitude

values of the source markers that you have activated. The cursor amplitude value and

frequency also printif you turn the cursor on (see Table 5-2).

5

Table 5-2. Example Printout for

PRINT MKRS

Markers

Frequency Chan. 1 Chan. 2

No. (Hz) (dBm) (dBm)

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

1 2.930125E+09

2 3.798676E+09

3 2.211325E+09

0

12.122 +2.570

0

12.207 +1.894

0

14.600 +2.886

Cursors

1 1.971725E+09

0

14.548 +2.701

d 2.06655E+09 +4.370 + .514

If you are using the alternate sweep mode, the printouts include the channel pair with the

active channel (channels 1 and 3 or c

hannels 2 and 4). T

o print the other pair, activ

ate one

of the channels in that pair and print again.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ABORT PRINT

terminates the printing of a hardcopy. The printing does not stop

immediately; it stops after the buer empties.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

# TRACE POINTS

lets you choose the number of data points that the analyzer uses to

process and display the measurement. If you select fewer points, the analyzer will have

lower resolution, but you can set faster sweep times. You can select a maximum of p oin

ts

(for each trace) depending on the number of traces you have displayed on the analyzer:

401 trace p oints for up to four traces displayed

801 trace p oints for up to two traces displayed

1601 trace p oints for only one trace displayed

The number of p oints you selected does not change at power on. However, at instrument

preset, the analyzer defaults to 401 points.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

FREQ LABELS

allows you to access the screen lab els, frequency lab els, clo ck, and title

functions.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

LABELS ON OFF

toggles the mo de labels, the frequency labels, and the analyzer displa

status line on and o.

If you activate any limit lines, the pass/fail indicator is not blank

ed until you disable the

limit lines.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

FRQ LBL OFF

turns o the frequency lab els, and blanks the source frequency readout. If

you press this softkey, the frequency lab els information will not get plotted or printed.

You can restore the frequency labels by presetting the analyzer, but this also resets the

frequency information to preset conditions.

y

HP 8757D Operating Reference INSTRUMENT STATE 5-5

4

SYSTEM

5

Even if you have the frequency lab els o when you save or store an instrument state, the

complete source instrument state information is included. However, when you recall the

instrument state, the frequency labels are o, reecting the state that you havesaved.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

See

CLEAR SAV/RCL

for additional information.

HP-IB programming commands also let you turn the frequency lab els o so you can

operate the analyzer in the secure frequency mo de. See \Secure Frequency Mo de" in any

of the remote operation documents.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

TITLE ON OFF

toggles the titles on and o without erasing the title.

NNNNNNNNNNNNNNNNN

CLOCK

allows you to set the time and date so they appear on measurement prints and plots.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CLOCK ON OFF

toggles the time and date function on and o. If the clock function is

on, the date and time will b e displayed on the analyzer and will also appear on any

measurement prints or plots.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ROUND SECONDS

sets the seconds of the analyzer clo ck to zero. The function also rounds

the seconds to the nearest minute.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SET MINUTES

terminated by pressing

allows you to set the minutes for the analyzer clo ck. Your entry must b e

4

5

.

ENT

NNNNNNNNNNNNNNNNNNNNNNNNNN

SET HOUR

allows you to set the hour for the analyzer cloc

terminated by pressing

4

ENT

5

.

k. Your entry must b e

NNNNNNNNNNNNNNNNNNNNNNN

SET DAY

be terminated by pressing

allows you to set the day of the month for the analyzer clo ck. Your entry must

4

5

.

ENT

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SET MONTH

must be terminated by pressing

allows you to set the month of the year for the analyzer clo ck. Your entry

4

5

.

ENT

NNNNNNNNNNNNNNNNNNNNNNNNNN

SET YEAR

terminated by pressing

allows you to set the year for the analyzer clo ck. Your entry must b e

4

5

.

ENT

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START FREQ

You can use this function only with the system interface o or without a source HP-IB

connection. After you select

keypad and terminate the entry with the appropriate units softkey (suchas

lets you specify the start frequency value that will appear at the left graticule.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START FREQ

,enter the start frequency with the numeric

NNNNNNNNNNN

GHz

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STOP FREQ

You can use this function only with the system in

connection. Engage this function the same wayas

lets you specify the stop frequency value that will appear at the right graticule.

terface o or without a source HP-IB

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START FREQ

.

or

NNNNNNNNNNN

MHz

).

Note

The frequency lab els are useful if you are making a swept measurement

without an HP-IB sweeper, or with the system interface o.

5-6 INSTRUMENT STATE HP 8757D Operating Reference

4

SYSTEM

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

N

MODE AC DC

toggles between AC and DC detection modes. If you connect a source to the

system interface, the analyzer automatically controls the source modulation (normally on for

AC and o for DC).

NNNNNNNNNNNNNNNNN

TITLE

allows you to dene a title that can app ear on the analyzer display and on a hardcopy.

You select eachcharacter of the title from the active entry area. The characters consist of the

letters of the alphabet, the digits 0 through 9, a decimal point, and the mathematical symbols

()+0/. =:.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT CHAR

repeatedly press the

the character you want. Press

enters a character you selected to b e included in the title. Turn the knob or

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE RIGHT

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT CHAR

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

or

STP ONE LEFT

and the character appears in the title.

softkey until the arrow points to

NNNNNNNNNNNNNNNNN

SPACE

inserts a blank space next to the last character you entered for the title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

BACK SPACE

deletes the last character you entered for the title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ERASE TITLE

deletes the entire title you just entered.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE RIGHT

moves the arrow pointer to the next character on the right.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE LEFT

moves the arrow pointer to the next character on the left.

NNNNNNNNNNNNNN

DONE

terminates the title entry and displays the system menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ADPT NM ON OFF

interpolates the calibration data stored in the analyzer memory when y

toggles adaptive normalization on and o. Adaptive normalization

ou reduce the

frequency span or change the number of points. This feature allows you to display a portion

of the calibrated frequency range without recalibrating. The resolution of the narro

wer range

does not change as you expand the trace. Do not use adaptive normalization if the device

response varies greatly with frequency.

5

An asterisk appears in the status symbols area for anychannel with adaptive normalization

engaged. If you expand the frequency range b eyond the calibrated range, the analyzer

extrapolates the calibration data outside that original frequency span as a straight line. In

this case, aUappears in the status symbols area.

NNNNNNNNNNNNNN

MORE

displays the continued portion of the system menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MOD ON OFF

toggles the analyzer rear panel modulation output on and o. Y

ou can use

this softkey to override the analyzer's automatic switching of the modulation on in AC

detection mode and o in the DC detection mode.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CLEAR SAV/RCL

connected compatible source. When you press this softkey, the analyzer displays

WANT TO CLEAR ALL REGISTERS, PRESS YES

clears all of the save/recall registers and presets both the analyzer and a

IF YOU

, and displays a menu where you can choose to

clear the storage registers.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CLEAR YES

clears all the analyzer save/recall registers and returns the channel menuto

the instrument preset state.

NNNNNNNN

NO

displays the prior system menu with all of the save/recall registers contents intact.

HP 8757D Operating Reference INSTRUMENT STATE 5-7

4

SYSTEM

5

Note

If you are working in a high-securityenvironment, you can congure the

analyzer to clear all save/recall registers each time you switch o the

instrumentpower. You can enable this function as follows:

1. Remove the battery (A3BT1) from the A3 CPU board. This prevents

storage of any register data. The internal self test now indicates a battery

failure at p ower up.

2. Install a wire jumper (A3W2) on the A3 CPU b oard, just below U2. This

jumper signals the CPU to skip the battery self-test so the analyzer can

resume normal operation. The analyzer briey displays a warning message

at eachpower cycle:

SAVE/RECALL registers defaulted

.

By removing the battery,you only aect the save/recall registers, not the

analyzer's internal calibration.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SWEEP MODE

presents a menu that allo ws you to specify the type of sweep supplied bya

source that is not compatible with the HP 8757 system interface.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

NONSTD ON OFF

volt ramp. The nonstandard sweep should be within the 0 to 10 v

enables the analyzer to tracka sweep ramp other than the typical 0 to 10

olt range or you must

modify the A4 ADC assembly (see the service manual for instructions). See Pro duct Note

8757-5 for a more detailed description of this mode.

To use the nonstandard sweep mo de, disconnect the POS Z BLANK, the STOP SWEEP

,

and the 8757 SYSTEM INTERFACE connections to the source. You must have the

SWEEP IN connected between the analyzer and source. The number of trace p oints you

selected still applies in the nonstandard sweep mo de.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CW ON OFF

interface. With

source to CW. If you use a source that is compatible with the HP 8757 system in

allows you to use a source that is incompatible with the HP 8757 system

NNNNNNNNNNNNNNNNN

CW ON

, the analyzer continuously updates the display when you set the

terface, the

analyzer selects this function automatically when you set the source to a CW mode.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MANUAL ON OFF

toggles the manual sweep control on and o. With the analyzer manual

function on, you can manually sweep the frequency range from the source. This function

also allows you to use a manual sweep input signal from a source that is not compatible

with the HP 8757 system interface.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SYSINTF ON OFF

toggles the analyzer's control of the HP 8757 system interface on and o.

With the analyzer's control OFF, another instrument on the HP 8757 system interface can

control the instruments connected to the interface.

Instrument preset does not change the setting of this function. When the analyzer's control

is o, the analyzer status line displays

SYS INTF OFF

.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STEP SW ON OFF

(available only with an HP 8340, 8360, or 83750 Series sources) toggles

the step-sweep mode on and o. If you are using the step-sweep mode you must connect the

source to the HP 8757 system interface.

5-8 INSTRUMENT STATE HP 8757D Operating Reference

4

SYSTEM

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

N

PLT BUF ON OFF

turns the plotter buer on and o. If you select a plot softkey with the

buer on, the analyzer will continue measuring a device response while the plotter makes a

hardcopy.However, not

all

active functions are available during a plot. If the buer is o, the

analyzer disables all active functions until a plot is nished. The analyzer is sent from the

factory with the plotting buer on. If you want the fastest plotting process, set the buer o.

NNNNNNNNNNNNNNNNNNNNNNN

SERVICE

displays the service menu, which allows you choose from a series of automated tests

that checkvarious analyzer functional blocks.

NNNNNNNNNNNNNNNNNNNNNNN

DISPLAY

allows you to view test patterns, verify the A14 circuitry, and adjust various CRT

displayintensity levels.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

HEX TESTS

checks many dierent parts of the instrument with read/write and rotate tests.

The CPU is instructed to access a user specied memory or I/O address and read or write

data from or to that address, or write a rotating 1 data pattern.

These tests use the hexadecimal (hex) numbering system: Hex digits from 0 to 9 and A to

F represent decimal numbers from 0 to 15. Each hex digit represents four binary digits or

bits. An address is sp ecied by six hex digits, while a data word is sp ecied by four hex

digits.

NNNNNNNNNNNNNNNNNNNNNNN

A1/2 FP

In some cases, you can prompt the analyzer to force a diagnostic test ev

presents a menu of tests the check the front panel knob, keys, and annunciators.

en if the front panel

is not working.

NNNNNNNNNNNNNNNNNNNN

A3 CPU

helps troubleshoot the A3 CPU assembly by accessing tests that check the RAM,

programmable timer, EEROM, and the read function.

NNNNNNNNNNNNNNNNNNNN

A4 ADC

helps to troublesho ot the A4 analog-to-digital converter assembly by accessing

tests that check the analog to digital signal converters, digital to analog signal converters,

detector control circuitry, and sweep operation.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

HP-IB TESTS

helps to troublesho ot the A6 HP-IB assembly bychecking HP-IB listen and

talk modes.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

INST VERIFY

performs nine major instrument self-checks.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

EXIT SERVICE

returns to normal operation by initiating an instrument preset.

5

HP 8757D Operating Reference INSTRUMENT STATE 5-9

4

LOCAL

5

4

LOCAL

The

5

| Local Menu

4

5

LOCAL

key returns the analyzer to lo cal op eration from the remote op eration state unless

Figure 5-3.

4

LOCAL

5

Key and Local Menu

a LOCAL LOCKOUT command has been received over HP-IB. The lo cal menu lets you set

HP-IB addresses for the analyzer and other instruments connected to the HP 8757 system

interface. Table 5-3 lists the default addresses for these instrumen

ts.

Table 5-3. HP-IB Default Addresses

Instrument HP-IB Address

8757 16

Sweeper 19

Plotter 05

Printer 01

Disk Drive 00

Changing a Default Address

Do not set two instruments to the same HP-IB address. Tochange a default address:

1. Select the softkey for the instrumentyou wish to change. The analyzer displays the current

HP-IB address.

2. Use the numeric keypad to enter a new address (0 through 29), and terminate the entry

with the

4

5

key. The analyzer shows the new HP-IB address and stores it in memory.

ENT

Be sure that the address you set for each instrument matches the address physically set on the

instrument.

5-10 INSTRUMENT STATE HP 8757D Operating Reference

4

SAVE

5

|Save Menus

4

SAVE

5

Figure 5-4.

The

4

5

key allows you to save the current instrument state in the analyzer's save/recall

SAVE

registers (non-volatile memory) or to store the instrument states, measurement data, data in

memory, and display graphics to a disk.

4

5

Key and Save Menus

SAVE

HP 8757D Operating Reference INSTRUMENT STATE 5-11

4

5

SAVE

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

N

SAVE REGISTR

displays

SAVE REG

saves the current instrument state in a storage register. The active entry area

. Using the numeric keypad, you can enter the number of the register where

you wish to store the current instrument state (no terminating key is needed).

You can store nine dierent settings in registers 1 through 9. The information saved in a

storage register depends on the register number used and on the channel number. All registers

save the analyzer front panel settings and the source front panel settings (if it is compatible).

Registers 1 through 4 also save titles. If channels 1 or 2 are saved in registers 1 through 4,

limit lines and memory trace data are also saved. The saved memory trace has 401 data

points regardless of the number of p oinsts you selected for the measurement.

You can recall saved information from a designated register unless you write over the register

contents, or clear the contents with the

Note

You can also save the current instrument state in a register by pressing

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CLEAR SAV/RCL

softkey.

4

SAVE

entering the number of the storage register.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STORE TO DISK

data, and display graphics to disk. You can create a unique le title to iden

presents a menu that lets you store instrument state, trace data, memory

tify the

information you store. If you don't create a le title, the analyzer will assign the stored

information a default le title (for example: FILE1). Refer to the gure b elo

w.

If you store the instrument states for an analyzer and source combination, and then load the

states into an analyzer with a dierent source, the original instrument states will apply to the

new source. Table 5-4 lists the source settings saved on disk.

Table 5-4. Source Settings Saved on Disk



ALC mode (internal, external, p ower meter)



CF/4F frequencies



CW frequency



displaymultiplier



display oset (HP 8350B only)



display update on/o



marker delta



marker sweep



markers 1 through 5



power slope



power sweep



RF power (on/o, value)



square wave mo dulation on/o (HP 8350B only)

or shift pulse modulation on/o (HP 8340/41/60)

or scalar pulse mo dulation on/o (HP 83750)



start/stop frequencies



sweep mode (start/stop, CF/4F, CW, swept CW)



sweep time



sweep trigger (internal, line, external)



sweep type (manual, external, continuous)

5

,

5-12 INSTRUMENT STATE HP 8757D Operating Reference

4

SAVE

5

Note

External disk drives for the HP/Agilent 8757D are no longer available from

Agilent.

Notes

You cannot save alternate state information or HP 8360 and 83750 Series user

atness data to disk.

Before you store anything to a new disk, you must initialize the disk. You

must also identify the disk unit where the disk resides, and the disk volume

number of a hard disk drive (see

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SET UP DISK

).

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

INSTRM STATE

stores the analyzer and source front panel settings to disk. The stored

information is assigned the le title that is shown on the analyzer. If the stored instrument

state data already exists under this le title, the analyzer writes the new data over the old

data. You can create a new title by pressing

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

TITLE FILE

in the save menu.

NNNNNNNNNNNNNN

MEAS

stores the trace measurement data to disk. The displayed title will b e assigned to the

data le unless you create a new le title.

NNNNNNNNNNN

MEM

stores the trace memory data to disk. The displa

yed title will be assigned to the data

le unless you create a new le title.

NNNNNNNNNNNNNNNNNNNNNNNNNN

MEAS-MEM

Stores normalized trace data to disk. The displayed title will be assigned to the

data le unless you create a new le title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CRT GRAPHIC

stores current analyzer graphics to disk. The displayed title will b e assigned

to the data le unless you create a new le title.

NNNNNNNNNNN

ALL

stores the instrument state, trace measurement, normalized trace, memory, and

analyzer graphics to disk in one op eration. This information is stored in separate les under

the active le title.

Note

When accessing stored data from a computer's disk driv

e, you will see that the

lename is a combination of the le title displayed in the HP 8757 directory

list plus a two letter sux. The following list shows the list of p ossible le

title suxes and the corresp onding denitions:

IS - instrument state

Dx - data for channel x

Mx - memory for channel x

Nx - normalized (MEAS0MEM)

CG - CRT graphics

x = 1, 2, 3, or 4

For example, the disk le \FILE1N3" contains MEAS0MEM for channel 3

and would be listed as FILE 1 normalization on the HP 8757 le directory.

HP 8757D Operating Reference INSTRUMENT STATE 5-13

4

5

SAVE

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

GRAPHIC ON OFF

toggles recalled graphics on and o. When this function is activated, the

analyzer only shows graphics and softkey menus. (This key only appears if the display list

contains a user generated display graphic.)

An example of howyou might use this function is when you want to access an instrument

connection diagram at any time during a measurement pro cess.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

GRAPHIC OFF

turns o the graphics and returns the instrument state and measurement

data.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

FILE DIRECT

shows you the directory of les on the specied disk. The directory can contain

up to 382 les, with 16 les to a page.

Figure 5-5. Directory of Stored Files

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

NEXT PAGE

shows you successive pages of the directory.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PREV PAGE

shows you previous pages of the directory.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT TITLE

the analyzer display.To select a le title, use the analyzer knob, or

through the directory and p ointtoyour title choice. Press

lets you select the active le title. The active le title app ears at the top of

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

4*54+5

SELECT TITLE

keys to scroll

to makeyour

title selection.

5-14 INSTRUMENT STATE HP 8757D Operating Reference

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

N

TITLE FILE

lets you create a new le title. The title area displays the current active le title.

To create a new le title, rst erase the active le title. Then enter up to eightcharacters.

The title area shows the new title as you create it.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT CHAR

character choice. Press

enters your character selection. Turn the analyzer knob to pointtoyour

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT CHAR

and the character will appear in the title area.

NNNNNNNNNNNNNNNNN

SPACE

enters a space character in your title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

BACK SPACE

deletes the last character entered in the title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ERASE TITLE

deletes the entire title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE RIGHT

moves the arrow pointer to the next character to the right.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE LEFT

moves the arrow pointer to the next character to the left.

NNNNNNNNNNNNNN

DONE

terminates entry of the title and returns the previous menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE FILE

deletes all the les from the directory that ha

example, FILE1. Selecting

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE FILE

ve the same le title. F

shows you the active le title. Make sure that the

or

les you wish to delete are active.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE YES

deletes all les in the directory with the active le title. If y

the les with the active le titles, press

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE YES

.

ou wish to delete

NNNNNNNN

NO

exits the delete le menu without deleting any les. If you want to delete les other

than the current active le, use

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT TITLE

or the le directory to change the active le

title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SET UP DISK

presents another menu that lets you set the disk unit and volume numbers,

initialize disks, and dene the format.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISK UNIT

When you select

shows the unit of the disk drive where the analyzer expects to nd your disk.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISK UNIT,DISK UNIT

appears in the analyzer activeentry area, along

with the unit number of the drive.

4

SAVE

5

Tochange the unit number, use the numeric keypad to enter the new unit number and

terminate the entry with the

4

ENT

5

key.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISK VOLUME

recall data. When you select this softkey,

shows you whichvolume of the disk drive the analyzer will access to save and

DISK VOLUME

appears in the analyzer active entry

area, along with the drivevolume number. The correct volume number is critical when

using a hard disk. Tochange the volume number, use the numeric keypad to enter the new

volume number and terminate the entry with the

4

ENT

5

key.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

BINARY FORMAT

sets the measurement and memory data format to binary. Binary format

provides the fastest transfer speed of data, includes the detector oset, and uses the

smallest storage space of the two formats available (binary and ASCII). The analyzer

highlights and underlines the chosen format, and presets to binary format.

HP 8757D Operating Reference INSTRUMENT STATE 5-15

4

5

SAVE

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

EXT BIN FORMAT

sets the measurement and memory data format to binary. Binary format

provides the fastest transfer speed of data, and uses the smallest storage space of the two

formats available (binary and ASCII). The analyzer highlights and underlines the chosen

format, and presets to binary format.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ASCII FORMAT

sets the measurement and memory data format to CITTI le format which

is a version of an ASCII format. This format makes the stored data compatible with other

computers.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

INIT DISK

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISK UNIT

lets you initialize a disk. The analyzer initializes the disk identied by

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

and

DISK VOLUME

. Be certain these are correctly set before continuing.

NNNNNNNNNNNNNNNNNNNNNNNNNN

INIT YES

message

begins the initialization. When the initialization pro cess is complete, the

WAITING FOR DISK

disappears from the analyzer display and the disk drive light

turns o.

Notes

It can take up to 30 minutes to initialize a hard disk.

For a write-protected disk, the analyzer displays

PROTECTED

the disk, remove the write protection and select

NNNNNNNN

NO

displays the previous menu without running the initialization. It does

initialization already in progress.

WARNING: DISK IS WRITE

and the initialization pro cess ab orts. If y

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

INIT DISK

ou still wish to initialize

NNNNNNNNNNNNNNNNNNNNNNNNNN

INIT YES

not

abort an

.

5-16 INSTRUMENT STATE HP 8757D Operating Reference

4

RECALL

5

4

RECALL

5

| Recall Menus

4

RECALL

Figure 5-6.

5

accesses function that allow you to recall information previously saved in the analyzer

4

RECALL

5

Key and Recall Menus

registers or on a disk.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

RECALL REGISTR

allows you to recall information saved in an analyzer storage register. Use

the numeric keypad to enter the number of the register that contains the information you

wish to recall (no terminator required). The analyzer retrieves the information saved in that

register, then

COMPLETE

appears in the active entry area.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

LOAD FR DISK

analyzer graphics from disk. The active le title (in the title area) iden

you want to load information from a dierent le, press

the le title of the desired le. Then press

presents a menu that lets you load the instrument state, trace data, and

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

LOAD FR DISK

PRIOR MENU

again.

ties the le to load. If

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

FILE DIRECT

and select

HP 8757D Operating Reference INSTRUMENT STATE 5-17

4

RECALL

5

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

INSTRM STATE

loads instrument front panel settings from disk. This information must have

been previously stored under the current active le title.

NNNNNNNNNNNNNN

MEAS

loads the measurement data from the disk into the measurement array for each

channel that has a le with the Dx sux, where x is the channel number. The analyzer

holds the trace, which means that the measurement data is no longer updated until you

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

turn

DISPLAY - HOLD

o. You can use the display, scale, ref, sp cl - smooth, and cursor

functions to display this data. A printer or plotter can generate a hardcopy of the displayed

trace.

NNNNNNNNNNN

MEM

loads trace memory data that was stored on disk. This information must have b een

previously stored under the current active le title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

TRACE DISPLAY

loads the trace data from the disk into the trace array for eachchannel

that has a le with the Nx sux, where x is the channel number. The analyzer holds

the trace, which means that the measurement data is no longer updated until you turn

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISPLAY - HOLD

o. You can use the scale, ref, and cursor functions to display this data.

A printer or plotter can generate a hardcopy of the displayed trace.

NNNNNNNNNNN

ALL

loads the instrument state, trace measurement and memory, and display graphics from

disk in one operation. This information must have been previously stored under the current

active le title.

NNNNNNNNNNNNNNNNNNNNNNNNNN

ALL HOLD

the tract data (Nx sux) from the disk. If the instrumen

two data les are found, then the measurement data is no longer updated until you turn

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISPLAY - HOLD

loads the instrument state (IS sux), measurement data (Dx sux), and/or

t state le and at least one of the

o. If trace data is loaded, you can view the data with the scale, ref, and

cursor functions. If measurement data is loaded, you can view the data with the display,

scale, ref, sp cl - smo oth, and cursor functions. A prin

ter or plotter can generate a hardcopy

of the displayed trace.

Note

If the stored le has smo othed data, smoothing turns o.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MEAS!MEM

loads trace measurement data from disk into the analyzer trace memory. This

information must have b een previously stored under the current active le title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CRT GRAPHICS

loads CRT graphics from disk. This information must have been previously

stored under the current active le title.

5-18 INSTRUMENT STATE HP 8757D Operating Reference

4

RECALL

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

N

FILE DIRECT

shows you the directory of les on the specied disk. The directory holds 382

les, with 16 les to a page.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

NEXT PAGE

shows you successive pages of the directory.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

PREV PAGE

shows you previous pages of the directory.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT TITLE

title appears at the top of the CRT. Use the analyzer knob to move the arrow to the le

title you wish to be the active le title. Press

lets you select a le title to be the active le title. The current active le

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT TITLE

.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

TITLE FILE

allows you to dene a new le title. The current active le title app ears in the

CRT title area. To create a new le title, rst erase the active le title. Then enter up to

eightcharacters. The new title app ears in the title area as you create it.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT CHAR

repeatedly press the

your character choice. Press

enters your character selections for the le title. Turn the analyzer knob or

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE RIGHT

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT CHAR

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

or

STP ONE LEFT

softkey until the arrow points to

and the character will appear in the title area.

NNNNNNNNNNNNNNNNN

SPACE

enters a space character in your le title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

BACK SPACE

deletes the last character entered in the le title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ERASE TITLE

deletes the entire le title.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE RIGHT

moves the arrow pointer to the next character to the right.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STP ONE LEFT

moves the arrow pointer to the next character to the left.

NNNNNNNNNNNNNN

DONE

terminates entry of the le title and displays the previous menu.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE FILE

deletes all the les from the directory that ha

FILE1. Pressing

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE FILE

shows you the active le title. Make sure that the les you

ve a common title. For example,

wish to delete are active.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE YES

delete the les with the active le titles, press

deletes all les in the directory with the active le title. If you do wish to

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DELETE YES

.

NNNNNNNN

NO

exits the delete le menu without deleting any les. If you want to delete les other

than the current active le, use

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SELECT TITLE

or the le directory to change the active le

title.

5

HP 8757D Operating Reference INSTRUMENT STATE 5-19

4

RECALL

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

N

SET UP DISK

5

presents another menu that lets you set disk unit and volume numbers,

initialize disks, and dene the format in whichtosave the data.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISK UNIT

shows you the unit of the disk drive where the analyzer expects to nd your

disk. Tochange the unit number, use the numeric keypad to enter the new unit number and

terminate the entry with the

4

ENT

5

key.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISK VOLUME

shows you whichvolume of the disk drive the analyzer will access to save and

recall data. Tochange the volume number, use the numeric keypad to enter the new volume

number and terminate the entry with the

4

ENT

5

key.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

BINARY FORMAT

sets the measurement and memory data format to binary. Binary format

provides the fastest transfer speed of data, includes the detector oset, and uses the

smallest storage space of the two formats available (binary and ASCII). The analyzer

highlights and underlines the chosen format, and presets to binary format.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

EXT BIN FORMAT

sets the measurement and memory data format to extended binary.

Extended binary format extends the range limits beyond the binary format (for ratio,

normalized ratio, p ower and normalized power measurements only). The range extension is

a function of the analyzer's detector amplitude oset. This format excludes the detector

oset; the value of the detector oset is contained in the instrument state le.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

ASCII FORMAT

sets the measurement and memory data format to ASCII. ASCII format

makes the stored data compatible with other computers.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

INIT DISK

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DISK UNIT

lets you initialize a disk. The analyzer will initialize the disk iden

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

and

DISK VOLUME

. Be certain these are correctly set before con

tied by

tinuing.

NNNNNNNNNNNNNNNNNNNNNNNNNN

INIT YES

begins the initialization. The message

WAITING FOR DISK

appears on the

analyzer display. When the disk is initialized, this message disappears and the disk driv

light turns o.

e

Note

For a write-protected disk, the analyzer displays the message

DISK IS WRITE PROTECTED

to initialize the disk, remove the write protection and press

NNNNNNNNNNNNNNNNNNNNNNNNNN

INIT YES

.

, and the initialization aborts. If you still wish

WARNING:

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

INIT DISK

NNNNNNNN

NO

returns the previous menu without running the initialization. It will

not

abort an

initialization already in progress.

5-20 INSTRUMENT STATE HP 8757D Operating Reference

4

PRESET

5

4

PRESET

When you press

controller, the analyzer p erforms a self-test and then presets all of the instrumen

5

| Preset Key

4

PRESET

5

Figure 5-7.

4

PRESET

5

Key

, or when the analyzer receives the IP command from a system

ts connected

to the HP 8757 system interface. All of the instrument's functions are turned o and the

following states are set:

Analyzer

power measurement A on channel 1 (on)

power measurement B on channel 2 (on)

power measurement C (or B) on channel 3 (o )

power measurement R on channel 4 (o )

measurement data in log magnitude format

scale =20 dB/div log; 10 dB/div SWR

reference level = 0 dBm for all channels log; 1.0 SWR

reference level step size = 20 dB

averaging is o

averaging factor = 8

cursor is o

all lab els are on

channel 1 is the active channel

modulation driveis on

number of trace points = 401

detector mode is set for AC detection

smoothing aperture is set for 5.0% of span (o )

cursor format = log magnitude

HP 8757D Operating Reference INSTRUMENT STATE 5-21

4

PRESET

5

searchvalue =03dB

adaptive normalization is o

temperature comp ensation is on

autocal is on

repeat autozero is o

detector oset = 0 dB

detector frequency is o

cursor and delta cursor position = 200

user start/stop frequency = 50 MHz

detector start/stop frequency = 50 MHz

memory oset = 0 dB

service request mask = 0 (if front panel preset)

non standard sweep is o

limit lines are o

frequency labels are unblanked

disk format = binary

detector oset calibrator power = 0 dBm

non swept CW is o

manual sweep is o

stepped sweep is o

data output format = ASCII

Source

instrument preset

sweep time = 200 ms

HP 8350B square wave modulation is on

HP 8340/8341 SHIFT PULSE on; RF output is on

HP 8360 scalar modulation on; RF output is on

Plotter

plot is ab orted, if in progress

P1 and P2 scaling points are unchanged

selection of plotter p ens are unchanged

Printer

plot or print is ab orted, if in progress

5-22 INSTRUMENT STATE HP 8757D Operating Reference

Disk Drive

data transfer in progress is aborted

unit number is unchanged

volume number is unchanged

ASCII or binary mo de is unchanged

Unchanged Analyzer Conditions

4

PRESET

5

4

PRESET

5

and the IP command do not change the following analyzer conditions:

reference position

trace memory

save/recall registers

HP-IB addresses

service request mask (if remote preset \IP")

limit lines

title

user-dened plot

HP 8757 system interface private bus control on/o

repeat autozero timer

displayintensity

display colors

time stamp on/o

plotter/printer buer on/o

HP 8757D Operating Reference INSTRUMENT STATE 5-23

Rear Panel Features

6

Figure 6-1. The HP 8757D Rear Panel

18757 SYSTEM INTERFACE

peripherals such as the source, plotter, and printer. Since the analyzer itself controls the

HP 8757 system interface bus, other controllers must not be attached to this connector,

unless the

With a system interface establishing a communication between the instruments, the

analyzer can detect and display the source frequency information.

2HP INTERFACE BUS

computer controller and other HP-IB instruments.

3POS Z BLANK

intensity marker (z-axis modulation) signals. The signal levels sensed on this input are

+5 V for blanking, 0 V for display,04 V for markers, and08 V for the active marker.

HP 8757D Operating Reference Rear Panel Features 6-1

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SYSINTF ON OFF

This input accepts positive retrace, bandswitch blanking, and negative

This interface is a private bus that lets the analyzer control

function iso.

This interface bus allows the analyzer to interface with a

Rear Panel Features

4SWEEP IN 0-10V

This input accepts a source sweep ramp signal that can be anywhere

between 0 to +10 volts. You can modify the A4 ADC assembly so the analyzer can

accept sweep ramps greater than +10V. The sweep in signal is necessary for the analyzer

to operate as a receiver. An HP 83750 source creates a pulse train that consists of 1

second pulses in both continuous and step sweep mo des.

5STOP SWEEP

This connector provides the interface signal to stop a source's sweep when

it is controlled over the system interface.

The analyzer also uses this connector to sense when the source has stopped the sweep.

6MODULATOR DRIVE

This output provides a 27.778 kHz square wave signal,

(nominally66 V open circuit), for driving an external modulator, a source's external

amplitude, or pulse modulation input.

7DAC OUT 0-10V

This connector is provided for future enhancements included with later

rmware revisions. You can also use this output for troubleshooting.

8



ADC IN

NNNNNNNNNNN

AUX

This connector shows an external voltage on the analyzer display using

. The connector is also referred to as AUX input. You can also use this input for

troubleshooting.

9CONTROL 1 and CONTROL 2

These connectors provide digital output signals (TTL

open-collector) as a convenience for driving other p eripheral equipment in an HP-IB

controlled system. The CONTROL 1 signal can be used as an oscilloscope trigger source

when continuous lo op service-related tests are p erformed.



NNNNNNNNNNNNNN

MEAS

4105

Internal CRT Display:

R, G, and B VIDEO OUTPUT|These connectors provide analog

red, green, and blue video signals that you can use to drive an external color monitor or

monochrome monitor. Any analog multisync monitor can b e used if it is compatible with

the analyzer's 25.5 kHz scan rate and video lev

0

0.3 V = sync, sync on green).

Internal LCD-Based Display:

Instruments with the LCD-based display are equipp ed with

els (1 V p-p, 0.7 V = white, 0 V = blac

a single VGA OUTPUT connector on the rear panel so that an external monitor ma

connected. See previous blue tab labeled \Installation," Figure 2-9.

4115

LINE V610%

This input connector accepts primary line voltage (100, 120, 220, or 240

V) to power the analyzer. Use the printed circuit selector board to set the correct line

voltage. See chapter 2, \Installation," for information on line voltage and fuse selection.

k,

ybe

6-2 Rear Panel Features HP 8757D Operating Reference

Operator's Check

Equipment Required

A

HP-IB cable

sweep oscillator mainframe

RF plug-in

detector

50 MHz bandpass lter

graphics plotter

::::::::::::: ::::::::::::::: :::::::::::::::::::: :::::::::::

HP 10833A/B/C/D

::::::::::: ::::::::::::::: :::::::::::::::::::: ::::::::

::::::::::::: ::::::::::::::: :::::::::::::::::::: ::::::::::::::: ::::::

:::::::::::::: ::::::::::::::: ::::::::::::::::::: ::::::::::::::: ::::::

::::::::::::::: ::::::::::::::: ::::::::::::::::::

HP PN 08757-80027

:::::::::::::::::: ::::::::::::::: ::::::::::::::::::: :::::::::::::

HP 8350B

HP 83592B

HP 85037A/B

HP 7440A

Description

The operator's check procedure veries that the analyzer is functioning correctly. It does not

verify all of the instrument specications, but it is an appropriate test for daily instrumen

t

verication, incoming inspection, or verication after repair or replacement of digital circuits.

The procedure consists of HP-IB and system in

terface checks, self-tests, and an insertion loss

measurement of a standard device.

Save the insertion loss data as a reference for comparison with future operator's c

hecks. Keep

the standard device exclusively for these operator's checks to minimize device variation. You

can modify this pro cedure to use other test devices and frequency ranges. But, to test the

analyzer's full dynamic range, your source must output +16 dBm.

HP 8757D Operating Reference Operator's Check A-1

Procedure

Figure A-1. Operator's Check Equipment Set-up

1. Toverify the instrument self-test, HP-IB, and system interface, perform the \HP Interface

Bus and HP 8757 System Interface" test in chapter 4 of the service manual.

2. Set up the equipment as shown in Figure A-1, with the detector connected to input A

of the analyzer. Connect the detector's RF input to the RF output of the source for a

\thru" (0 dB insertion loss) connection. Turn on the instruments and allow 30 minutes

warm-up time.

ys

3. If the HP 8757 system interface is not engaged (the analyzer status line displa

OFF

), press

4.
On the analyzer, press

4

SYSTEM

NNNNNNNNNNNNNN

5

MORE

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SWEEP MODE

4

PRESET

5

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

SYSINTF ON

.

. The analyzer channel 1 should be is active and measuring

SYSINTF

input A.

5. Adjust the start and stop frequencies of y

our source to include the frequency range of y

our

microwave test device.

These frequencies will be plotted with the data.

6. Turn o the analyzer's channel 2 by pressing CHANNEL

7.

On the analyzer, press

4

CURSOR

5

NNNNNNNNNNN

MAX

to place the cursor at the maximum value of the

4

2

5

twice.

trace. The CRSR value is displayed in the active entry area of the analyzer. Adjust the

output power of the RF plug-in until the cursor value on the analyzer reads +16 dBm.

This value is the upper limit of the dynamic range of the analyzer.

8.

Press

displays

4

DISPLAY

CHAN 1 MEAS TO MEMORY

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

5

MEAS!MEM

to store the trace in memory. The analyzer message line

.

A-2 Operator's Check HP 8757D Operating Reference

9.

Disconnect the detector from the RF output of the source. Press

4

AVG

5

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

AVG ON OFF

turn on averaging with and average factor of 8. Wait a few seconds to allow the trace to

settle.

NNNNNNNNNNN

10. Press

4

CURSOR

5

MAX

. A cursor value of060 dBm or lower should be displayed in the

active entry area. This is the noise oor power level.

to

11. Insert your test device between the RF output of the source and the detector. On the

analyzer, press

12.

Press

4

CURSOR

4

DISPLAY

NNNNNNNNNNN

5

MAX

NNNNNNNNNNNNNNNNNNNNNNNNNN

5

MEAS-MEM

.Wait a few seconds to allo w the trace to settle.

to nd the trace maximum. The

CRSR

value displayed in the active

entry area now represents the minimum insertion loss of your test device. This value will

be plotted with the data trace.

13.

Press

4

SYSTEM

NNNNNNNNNNNNNN

5

PLOT

NNNNNNNNNNNNNNNNNNNNNNNNNN

PLOT ALL

to generate a hard copy plot. Keep this plot for

comparison with results of future operator's checks.

14. Disconnect the detector from the A input and connect it to the B input. Removeyour

test device from the circuit and connect the input of the detector to the RF output of the

source. Press

15.
Repeat step 14 for the remaining detector inputs, pressing

4

DISPLAY

NNNNNNNNNNNNNN

5

MEAS

4

MEAS

NNNNN

5

B

4

AVG

NNNNNNNNNNNNNNNNNNNNNNN

5

AVG OFF

. Repeat steps 7 through 13.

4

5

MEAS

and selecting the softkey

that corresponds to the detector input connected.

HP 8757D Operating Reference Operator's Check A-3

Softkey Menu Structure Maps

B

HP 8757D Operating Reference Softkey Menu Structure Maps B-1

Figure B-1. HP 8757D Softkey Menu Structure Map

B-2 Softkey Menu Structure Maps HP 8757D Operating Reference

Figure B-2. HP 8757D Softkey Menu Structure Map

HP 8757D Operating Reference Softkey Menu Structure Maps B-3

Figure B-3. HP 8757D Softkey Menu Structure Map

B-4 Softkey Menu Structure Maps HP 8757D Operating Reference

Figure B-4. HP 8757D Softkey Menu Structure Map

HP 8757D Operating Reference Softkey Menu Structure Maps B-5

C

Performing an External Calibration

Performing an External Detector Calibration with an HP 85025C

Because the HP 85025C is used with an external (separate) detector diode, you should

perform a rmware based measurement calibration procedure. This external detector

measurement calibration procedure calibrates the analyzer's dynamic range to each detector

diode and detector adapter. You should p erform this procedure whenever you connect a

detector diode and adapter to a dierent input, or if you change either the detector or the

adapter.

External Detector Measurement Calibration

The response of the diode's output v

oltage versus input power is describ ed by a general

equation within the HP 8757D. To adapt this equation to describ e your particular detector,

the analyzer uses data measured at two points on the detector's p ower range. The external

detector measurement calibration requires that you measure two dierentpower levels (HI and

L0) and that you enter the exact values of the power levels. For best results, the HI p ower

level should be in the diode detector's linear region of op eration, and the LO p o

wer level

should be in its square law region. The p ower levels +6 and024 dBm used in the following

procedure are typical examples. The power levels you choose depend on the response of y

our

diode detector, and the output p ower of your source.

Equipment required:

HP 8757D

HP 85025C detector adapter

On the HP 8757D:

1. Connect the equipment and allo w 30 minutes warm up.

2. Press

3. If you will be using DC detection, press

4

PRESET

5

.

4

SYSTEM

5

and select

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

MODE AC/DC

.

If you will be using AC detection, continue with Step 4.

NOTE: A measurement calibration in one mode is not valid for the other (see ACversus DC

Measurement Calibration below).

4. Press

4

CAL

5

5. Select the appropriate input being calibrated, suchas

NNNNNNNNNNNNNN

MORE

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

EXT DET CAL

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DET PWR CAL

.

NNNNNNNNNNNNNNNNN

DET A

.

If you are using AC detection, the analyzer displays:

ENTER POWER (HI).

Go to Step 8.

If you are using DC detection, the analyzer displa

ys:

Adjust COARSE ZERO for minimum response.

HP 8757D Operating Reference Performing an External Calibration C-1

On the HP 85025C:

6. Adjust COARSE ZERO on the detector for a minimum noise level signal on the analyzer.

On the HP 8757D:

NNNNNNNNNNNNNN

7. Select

CONT

.

The analyzer displays

ENTER POWER (HI).

8. Connect the detector to an RF source, suchasasweeper.

On the source:

9. Select a CW frequency within the detector's range.

10. Set the power to a level in the detector's square law region greater than010 dBm (for

example, +6 dBm). For best accuracy, use a power meter or HP 85037 detector to set the

power level.

On the HP 8757D:

13. Enter the power level incident on the detector (for example, 6 dBm). The analyzer

displays

ENTER POWER (LO).

14. Set the attenuator or source power level so that the power to the detector is in the square

law region, and less than020 dBm (for example, 30 dB of atten

uation).

15. Enter the power level incident on the detector (for example,024 dBm).

The analyzer p erforms the external detector measurement calibration and displays the

DET A(BCR) CAL VAL

when it is nished. Record this value for future reference (on the

detector diode and detector adapter, if possible).

If you change the detector or the detector adapter, you must perform a new measurement

calibration.

The displayed value is retained by the analyzer as long as an HP 85025C is connected to that

input. If another detector dio de and adapter is connected to the same input, the analyzer uses

the rst measurement calibration value until you perform a new measurement calibration.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

You can bypass the measurement calibration pro cedure if you select the softkey

rather than

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DET PWR CAL

in the measurement calibration sequence, and enter the known

CAL VALUE

value for your detector dio de and detector adapter.

ACversus DC Measurement Calibration

A measurement calibration p erformed in one measurementmodemay not be valid in the other

mode. For the best measurement accuracy, perform a measurement calibration in the mode

you will be using.

The dierence b etween an AC and a DC mo de measurement calibration dep ends on the

detector you use. All detectors do not resp ond the same to a modulated RF signal (used in

AC detection), some resp ond very quickly, while others respond more slowly.

A detector that responds very quickly produces an output signal that has the same amplitude

in either AC or DC mo de.

A detector that responds more slowly,however, pro duces an output signal that is smaller in

amplitude in AC mo de than in DC. Because the signal amplitude is not the same in b oth

measurement modes, a power calibration done in one is not v

alid in the other.

C-2 Performing an External Calibration HP 8757D Operating Reference

Changing a Stored Measurement Calibration

When you perform the measurement calibration procedure, the analyzer stores the calibration

value. The analyzer retains that value unless you change it. You can change a calibration

value in three ways:

1. Perform an external detector measurement calibration with a new diode and adapter. The

new calibration value replaces the original.

2. Enter a known calibration value manually by pressing:

NNNNNNNNNNNNNN

4

5

,

MORE

CAL

displays

for that input and press

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

,

EXT DET CAL

DET A CAL VAL

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

,

CAL VALUE

NNNNNNNNNNNNNNNNN

,

DET A

(or the appropriate input). The analyzer

and the value stored for that input. Enter the value you wish stored

4

5

. The analyzer displays

ENT

DET A CAL VAL

and the new value.

3. Use the default calibration value that is stored in the analyzer (see \Uncalibrated

Operation" b elow).

Only one measurement calibration value is stored at a time for each input; the analyzer do es

not keep separate AC and DC calibration values.

Uncalibrated Operation

When you are making relative measurements at lowpower levels (in the diode detector's

square law region), you don't have to p erform a measurement calibration. The analyzer has a

default calibration value that describes the response of a t

ypical detector dio de and adapter.

Accurate absolute p ower measurements, however, do require a calibration.

To set the default value:

Press

4

5

,

MORE

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

CAL

RESET CAL VAL

The analyzer displays

NNNNNNNNNNNNNN

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

,

EXT DET CAL

.

DET A CAL VAL

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

,

CAL VALUE

NNNNNNNNNNNNNNNNN

,

DET A

and the default value.

(or the appropriate input)

Zeroing

When you make DC detection measurements, it is important that you perform a zeroing

operation to compensate for the eects of DC drift and temperature uctuations (this is not

required for AC detection). The zeroing operation eliminates small DC voltages from the

diode detector that would otherwise cause amplitude measurement errors at low(040 dBm

and below) p ower levels. Zeroing also establishes the displayed noise level (noise oor of the

system) with no RF signal applied.

Zeroing the HP 85025C consists of two parts: (1) coarse zero, which compensates for any large

oset voltage, and (2) autozero, which compensates for any small drift in the oset voltage.

Coarse Zero:

1. Connect the diode and adapter to the analyzer.

On the HP 8757D:

2. Turn the analyzer on and press

4

PRESET

5

. Allow the instruments to warm up for 30

minutes.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

3. Press

4.

Press

4

SYSTEM

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

4

5

DC DET ZERO

CAL

5

MODE AC/DC

to turn DC mode on.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

COARSE ZERO

.

HP 8757D Operating Reference Performing an External Calibration C-3

5. Select the softkey that corresp onds to the detector adapter that you wish to zero (for

example,

NNNNNNNNNNNNNNNNN

DET A

). The analyzer displays

Adjust COARSE ZERO for minimum response

On the HP 85025C:

6. Adjust Coarse DC Zero for a minimum signal on the analyzer.

Autozero:

On the HP 8757D:

NNNNNNNNNNNNNN

7. After adjusting coarse zero, press the softkey

CONT

. The analyzer performs an autozero.

If the error voltage is too large for autozero to comp ensate for, the analyzer displays the

message:

WARNING: DC DET ZERO failed on A(BCR)

.

If this happens, you must adjust coarse zero to bring the error voltage within Autozero

range.

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

Repeat autozero,

REPT AZ ON/OFF

, perio dically repeats the autozero. Your must use the

detector with an HP-IB sweeper to use this function because the HP 8757 must be able to

turn o the RF power b efore performing the autozero.

NNNNNNNNNNNNNNNNNNNN

Manual zero, (

MANUAL

), is similar to zeroing a po

from the detector. Then press

NNNNNNNNNNNNNNNNNNNN

MANUAL

to perform the zeroing.

wer meter. First, remove the RF signal

.

Note

Note

If a device under test generates RF signals or noise, autozero is not v

Devices that can generate RF energy are microw

with the lo cal oscillator signal applied. If y

ave ampliers and mixers

ou are testing such devices, use

alid.

manual zero.

For optimum performance, you should electrically connect the outer conductor

of the source RF output connector to the outer conductor of the detector

adapter input.

If the operating environmentchanges signicantly,you should repeat the

zeroing operation.

C-4 Performing an External Calibration HP 8757D Operating Reference

Measurement Applications

Mixer Measurements

Equipment Required

2 HP 8360 synthesized sweepers

HP 85037A/B detector

HP 85027A/B/C bridge

HP 11667A/B p ower splitter

D

Figure D-1. Mixer Lab Equipment Set-up

Note

Here are three examples of mixer measurements:

1. Swept RF frequency, Fixed LO, LO<RF Frequency

(LO is not swept.)

2. Swept LO, LO frequency=RF0OFFSET

Note: in this case the LO sweeper must be slaved to the RF sweeper.

3. Fixed LO, LO>RF (The IF signal from the mixer sw

HP 8757D Operating Reference Measurement Applications D-1

The gure ab ove shows the connection for the mixer measurements described

in case 1 and case 3 in Table D-1.

If you want to make the mixer measurement described in case 2, you

must connect a cable between the HP 83750's AUXILIARY INTERFACE

connectors and connect a cable between the HP 83750's 10 MHz REF

IN/OUT connectors.

eeps downward in frequency.)

Table D-1. Three Mixer Measurement Cases

CASE Main Source RF External

Mixer IF out

Source LO

1) Fixed LO, LO<RF 10 to 15 GHz swept 9 GHz xed Start 1 GHz to Stop 6 GHz

2) Swept LO, LO=RF0OFFSET 10 to 15 GHz swept 9 GHz to 14 GHz 1 GHz Fixed

3) Fixed LO, LO>RF 10 to 15 GHz swept 16 GHz xed Start 6 GHz to Stop 1 GHz

The HP 85037 precision detector has built-in frequency resp onse correction constants. To

obtain the b est accuracy in mixer measurements, the detector start and stop frequencies

should be entered into the HP 8757D using the

NNNNNNNNNNNNNNNNNNNNNNNNNN

DET FREQ

function. If you don't enter the

frequencies into the HP 8757, the analyzer uses the source's frequency settings to create the

detector's frequency response corrections. This is recommended when you are making mixer

measurements because the HP 8757D uses the source's frequency settings to apply the HP

85037 detector's frequency response corrections.

In mixer measurements, the detector op erating frequency will most likely b e oset from the

source frequency.For example, in case 1:

Press:

4

5

CAL

NNNNNNNNNNNNNN

MORE

NNNNNNNNNNNNNNNNNNNNNNNNNN

DET FREQ

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

START FREQ

NNNNNNNNNNNNNNNNNNNNNNNNNNNNN

STOP FREQ

NNNNNNNNNNNNNNNNN

DET B

4

5

1

NNNNNNNNNNN

4

5

GHz

6

NNNNNNNNNNN

GHz

NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN

DET FREQ ON

NNNNNNNNNNNNNNNNNNNNNNNNNN

Refer to the

DET FREQ

section in chapter 4 of the \Operating Reference" for more

information.

D-2 Measurement Applications HP 8757D Operating Reference