Tektronix 1705A User Manual
Instruction Manual
1705A
Spectrum Monitor (SN B040000 and Above)
070-8222-08
Warning
The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
perform any servicing unless you are qualified to
do so. Refer to all safety summaries prior to
performing service.
www.tektronix.com
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176 - FAX 781.665.0780 - TestEquipmentDepot.com
Table of Contents
General Safety Summary ix..............................................
Service Safety Summary xi..............................................
Preface xiii.............................................................
Contacting Tektronix xv
Introduction
Section 1 Introduction 1--1................................................
Typical Configurations 1--1...................................................
Options 1--2...............................................................
Accessories 1--2............................................................
Standard Accessories 1--2.................................................
Optional Accessories 1 --3.................................................
Safety Information 1--3......................................................
ELECTRICAL SPECIFICATION 1--4..........................................
APPLICA TIONS 1--9........................................................
Locating Satellites 1-- 9...................................................
Satellite Footprints 1--10...................................................
Using the 1705A for Satellite Communication 1--11................................
L--Band Input Signals 1--12....................................................
Zeroing in on a Satellite 1--13..................................................
Locating the Satellite 1--13.................................................
Identifying the Satellite 1--13...............................................
Finding The Correct Transponder 1--15.......................................
Optimize Signal Strength 1--15..............................................
Looking at Exciters with the 70 MHz Input 1--16...............................
Miscellaneous Uses for the 1705A 1--17..........................................
Operating Instructions
Section 2 Operating Instructions 2--1.......................................
Front-panel Controls and Indicators 2--1.........................................
FILTER 2--1............................................................
INPUT 2--1............................................................
SWEEP 2--2............................................................
DISPLAY 2--3..........................................................
POSITION 2--4.........................................................
POWER 2--4...........................................................
Rear--Panel Connectors 2--4...................................................
INPUTS 2--4...........................................................
POWER 2--5...........................................................
Powering--up 2--6...........................................................
Measurement Graticule 2--7...................................................
1705A Spectrum Monitor
i
Table of Contents
Installation
Section 3 Installation 3--1.................................................
Vertical Scales 2--7......................................................
Horizontal Scales 2 --9....................................................
Center Frequency Readout 2--11................................................
Customizing Frequency Readout 2--14...........................................
Turning On or Off Readout 2--14............................................
Changing Readout Position 2--14............................................
Changing Readout Frequency 2--15..........................................
Test Mode 2--17..........................................................
Locating Ku--Band Satellites 2--17..............................................
Basic Operating Procedure 2--17............................................
Packaging 3--1..........................................................
Electrical Installation 3--1....................................................
Power Source 3--1.......................................................
Mains Frequency and Voltage Ranges 3--1....................................
+18 Volts For Block Down Converter 3--1....................................
Operating Options 3--2...................................................
Mechanical Installation 3--2...................................................
Cabinet Options 3--2.....................................................
Cabinetizing 3--4........................................................
Rack Adapter 3--5.......................................................
Custom Installation 3--8..................................................
Theory of Operation
Section 4 Theory of Operation 4--1.........................................
Overview 4--1..............................................................
Block Diagram 4--1.........................................................
RF Input Circuits (Diagram 1) 4--1..........................................
IF Amplifier Circuits (Diagram 2) 4--2.......................................
Sweep Generator Circuits (Diagram 3) 4--2...................................
Deflection Amplifiers (Diagram 4) 4--3......................................
Microprocessor (Diagram 5) 4--3...........................................
Front Panel (Diagram 6) 4--3..............................................
Low Voltage Power Supply (Diagram 7) 4--3..................................
High Voltage (Diagram 8) 4--4.............................................
RF Input
L--Band Input 4--4.......................................................
70 MHz Input 4--4.......................................................
70 MHz Local Oscillator 4--5..............................................
IF Amplifier
2nd Local Oscillator 4--5..................................................
Input Filter, Mixer, and IF Amplifier 4--6.....................................
Resolution Filter and Log Detector 4--6......................................
Sweep Generator
Diagram 1 4--4..................................................
Diagram 2 4--5..................................................
Diagram 3 4--7..................................................
ii
1705A Spectrum Monitor
Ramp Generator 4--7.....................................................
Gain Control (SPAN/DIV) 4--7.............................................
Sweep Shapers 4--7......................................................
Bright--Up Generator 4--8.................................................
Z--Axis Control 4--9.....................................................
Deflection Amplifiers
Diagram 4 4--9..................................................
Buffers 4--9............................................................
Vertical Deflection Amplifier 4 --10..........................................
Horizontal Deflection Amplifier 4--10........................................
Microprocessor
Diagram 5 4--11..................................................
Microprocessor 4--11......................................................
Readout 4--12...........................................................
Trace Rotate 4--12........................................................
Graticule Lights 4--12.....................................................
Front Panel
Diagram 6 4--12..................................................
Indicators, Controls, and Switches 4--12......................................
+18 Volt Supply 4--13.....................................................
Low Voltage Power Supply
Diagram 7 4--14..................................................
Line Rectifier and Filter 4--15..............................................
Pulse Width Modulator 4--15...............................................
Output Filters 4--16.......................................................
Error Amplifier 4--16.....................................................
Feedback Transformer Driver and Peak Detector 4--16...........................
Output Under-Voltage Shutdown 4--16........................................
High Voltage Power Supply
Diagram 8 4--17..................................................
HV Osc and Error Amp 4--17...............................................
Power Supply Outputs 4--18................................................
Focus Amplifier 4 --18.....................................................
Grid Drive Circuit 4--18...................................................
Z-Axis Amplifier 4--18....................................................
Table of Contents
Checks and Adjustments
Section 5 Checks And Adjustments 5--1.....................................
Recommended Equipment List 5--1.............................................
Electrical Instruments 5--1................................................
Auxiliary Equipment 5 --2.................................................
Performance Check 5--3......................................................
Short-Form Procedure 5--3................................................
Long Form Procedure 5--5................................................
Adjustment Procedure 5--17....................................................
1705A Spectrum Monitor
iii
Table of Contents
Short--Form Procedure 5--17................................................
Long Form Procedure 5--18................................................
Maintenance 6- - 1..........................................
Section 6 Maintenance 6--1................................................
PREVENTIVE MAINTENANCE 6--1..........................................
Cleaning 6--1...........................................................
V isual Inspection 6--2....................................................
Static--Sensitive Components 6--2..........................................
Performance Checks and Readjustments 6--3..................................
TROUBLESHOOTING 6--3..................................................
Diagnostic Routines 6--4.....................................................
Memory Test 6--5.......................................................
DAC Test 6--7..........................................................
LED and Key Tests 6-- 8..................................................
Troubleshooting Aids 6--8....................................................
Foldout Pages 6--8.......................................................
Parts Lists 6--9..........................................................
Major Assembly Interconnection 6--10........................................
General Troubleshooting Techniques 6--10....................................
Power Supply Troubleshooting Procedure 6--12....................................
Introduction 6--12........................................................
Low Volts Supply 6--13....................................................
High Volts Supply 6--15...................................................
CORRECTIVE MAINTENANCE 6--18..........................................
Obtaining Replacement Parts 6--18..............................................
Test Selected Components 6--18.............................................
Mechanical Disassembly/Assembly 6--19.........................................
Bezel Removal 6-- 19......................................................
Graticule Light Removal and Replacement 6--20...............................
Removal of the CRT 6--21.................................................
Replacing the CRT 6--21...................................................
Removal of the Rear Panel 6--22............................................
Removal of Front--Panel Assembly 6--22......................................
Removing the L--Band Tuner 6--23..........................................
Removing the 70 MHz Tuner 6--24..........................................
Removal and Replacement of the Main Board 6--24.............................
Removal and Replacement of the Power Supply Board 6--25......................
Removing the LNB Power Supply Board 6--26.................................
REPACKAGING 6--27........................................................
Options
iv
Section 7 Options 7--1....................................................
Options 7--1...............................................................
Field Upgrade Kits 7--1......................................................
ORDERING 7--2...........................................................
1705A Spectrum Monitor
Replaceable Electrical Parts
Section 8 Replaceable Electrical Parts 8--1...................................
Parts Ordering Information 8-- 1................................................
Using the Replaceable Electrical Parts List 8--1...................................
Cross Index--Mfr. Code Number to Manufacturer 8--1...........................
Abbreviations 8--1.......................................................
List of Assemblies 8--1...................................................
Column Descriptions 8--2.....................................................
Component No. (Column 1) 8--2.........................................
Tektronix Part No. (Column 2) 8--2.........................................
Serial/Assembly No. (Column 3 a nd 4) 8--2...................................
Name and Description (Column 5) 8--2......................................
Mfr. Code (Column 6) 8--2........................................
Mfr. Part No. (Column 7) 8--2..............................................
Diagrams/Circuit Board Illustrations
Replaceable Mechanical Parts
Table of Contents
Section 10 Replaceable Mechanical Parts 10--1................................
Parts Ordering Information 10--1................................................
Using the Replaceable Mechanical Parts List 10--1.................................
1705A Spectrum Monitor
v
Table of Contents
List of Figures
Figure 1-1: 1705A used to locate satellites and determine maximum signal level 1--2.........
Figure 1-2: Relationship of a communications satellite to earth 1--9.......................
Figure 1-3: Angle A (the difference at a specific latitude between the angle to the sun
and the angle to a satellite) 1--10.........................................
Figure 1-4: Sample longitudinal map of the Ku-Band satellites 1--11.......................
Figure 1-5: The western spot beam footprint for one Ku-Band satellite 1--12.................
Figure 1-6: A computer representation of the 1705A display showing the 12.198 GHz
horizontally polarized telemetry beacon on the SATCOM K2 satellite 1--14........
Figure 1-7: Transponder assignments for a typical Ku--Band, 16--transponder satellite
that employs alternate polarization 1--15....................................
Figure 1-8: Simulation of a 1705A FULL SPAN/DIV display 1--16.......................
Figure 1-9: Up link Video Exciter, Up converter, and High Power Amplifier (HPA) showing
how to hook up a 1705A Spectrum Monitor to look at the Video Exciter output 1--17
Figure 1-10: 1705A hooked up to look at either the output of the Video Exciter (70 MHz)
or the Receiver Input (L-Band) 1--18.......................................
Figure 2-1: 1705A front panel 2--2.................................................
Figure 2-2: 1705A rear panel controls and connectors 2--5..............................
Figure 2-3: 1705A display when powered up in L-BAND and FULL SPAN 2--6.............
Figure 2-4: 1705A graticule scale 2--7..............................................
Figure 2-5: Relationship of sweep to graticule showing minimum and maximum frequencies 2--10
Figure 2-6: Frequency relationship to horizontal graticule scale 2--11.......................
Figure 2-7: Center frequency cursor and readout for the L-Band with FULL SPAN/DIV 2--12...
Figure 2-8: 1705A CRT with the SCALE turned down 2--13.............................
Figure 2-9: The setting of the HORIZONTAL POSITION control can displace the location
of the displayed center frequency 2--13.....................................
Figure 2-10: Using the 1705A menus 2--15...........................................
Figure 2-11: An example of the readout displayed while satellite frequency is being set 2--16....
Figure 3-1: L-BAND INPUT connector and controls 3--2...............................
Figure 3-2: Dimensions of the 1700F00 plain cabinet 3--3...............................
Figure 3-3: 1700F02 portable cabinet dimensions 3--4..................................
Figure 3-4: Cabinet securing screws 3--5............................................
Figure 3-5: The WFM7F05 side-by-side rack adapter 3--5...............................
Figure 3-6: A WFM7F05 with a blank front panel (1700F06) 3--6........................
Figure 3-7: WFM7F05 rack mount cabinet with a 1700F06 utility drawer 3--7...............
vi
1705A Spectrum Monitor
Table of Contents
Figure 3-8: Considerations for custom installation of an instrument 3--8....................
Figure 4-1: 1705A L--Band comb display showing the areas each of the six sweep shaper
variable resistors adjust 4--8.............................................
Figure 4-2: Output duty cycle of the pulse width modulator used in the +18 V Power Supply 4--13
Figure 4-3: Pinout of the CRT Socket 4--19...........................................
Figure 5-1: Initial equipment connections 5--6........................................
Figure 5-2: Check time mark graticule alignment 5--8..................................
Figure 5-3: Output of the SG503 connected directly to the 1705A 70 MHz INPUT 5--9.......
Figure 5-4: Equipment connections for L--Band checkout 5--12...........................
Figure 5-5: Aligning L--Band time markers with the graticule lines 5--13....................
Figure 5-6: Using the UHF Signal Generator to check L--Band Span/Division, Readout, Gain,
and Flatness 5--14.....................................................
Figure 5-7: Adjustment locations 5--19...............................................
Figure 5-8: DAC check waveforms used to check Focus, Astigmatism, Geometry, and setting
of the Trace Rotation 5--20..............................................
Figure 5-9: Location of the shorting strap used when adjusting sweep length 5--21............
Figure 6-1: Using the 1705A menus 6--4............................................
Figure 6-2: 1705A Test menu, displayed when Test is the Main menu selection 6--5..........
Figure 6-3: 1705A CRT display when the NOVRAM Test has been successfully completed 6--6
Figure 6-4: 1705A power up error message 6--7.......................................
Figure 6-5: DAC check waveform 6--8.............................................
Figure 6-6: Circuit board assembly locations 6--9.....................................
Figure 6-7: Multiple pin connectors used in the 1705A Spectrum Monitor 6--11..............
Figure 6-8: Bezel securing screws 6--20..............................................
Figure 6-9: Screws securing the rear panel 6--22.......................................
Figure 6-10: Screws securing the front panel board (A2) in place 6--23.....................
Figure 6-11: Screws holding the Main board (A3) and the Tuners (A5 and A6) in place 6--24....
Figure 6-12: Removing the Power Supply board 6--26...................................
Figure 6-13: Mounting screws for the LNB Power Supply circuit board, A4 6--26.............
Figure 6-14: Repackaging a 1705A instrument 6--27....................................
1705A Spectrum Monitor
vii
Table of Contents
List of Tables
Table 1--1: Spectrum Display 1--4.................................................
Table 1--2: CRT Display 1--5.....................................................
Table 1--3: Power Source 1--5....................................................
Table 1--4: Environmental Characteristics 1--6.......................................
Table 1--5: Physical Characteristics 1--6............................................
Table 1--6: Certifications and Compliances 1--6......................................
Table 2--1: dB Reference 2--8.....................................................
Table 2--2: dBm to mv Conversion 2--9............................................
Table 2--3: Azimuth / Elevation Table for 21 CONUS Cities 2--18........................
Table 3--1: Internal Jumper Selection 3--2...........................................
Table 5--1: Preliminary Control Settings 5--6.........................................
Table 5--2: Preliminary Control Settings 5--18.........................................
Table 6--1: Static Susceptibility 6--2................................................
Table 6--2: Power Supply Fault Symptoms 6--12......................................
Table 6--3: Low Volts Supply Voltages 6--13.........................................
Table 6--4: Control Circuit Test Points 6--15..........................................
Table 6--5: High Volts Supply Fault Symptoms 6--16...................................
Table 6--6: High Voltage Oscillator Test Points 6--17...................................
Table 6--7: Test Selectable Components 6--19.........................................
Table 7--1: Power Cord Options 7--1...............................................
viii
1705A Spectrum Monitor
General Safety Summary
Review the following safety precautions to avoid injury and prevent damage to
this product or any products connected to it. To avoid potential hazards, use this
product only as specified.
Only qualified personnel should perform service procedures.
While using this product, you may need to access other parts of the system. Read
the General Safety Summary in other system manuals for warnings and cautions
related to operating the system.
ToAvoidFireor
Personal Injury
Use Proper Power Cord. Use only the power cord specified for this product and
certified for the country of use.
Connect and Disconnect Properly. Do not connect or disconnect probes or test
leads while they are connected to a voltage source.
Ground the Product. This product is grounded through the grounding conductor
of the power cord. To avoid electric shock, the grounding conductor must be
connected to earth ground. Before making connections to the input or output
terminals of the product, ensure that the product is properly grounded.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings
and markings on the product. Consult the product manual for further ratings
information before making connections to the product.
Connect the ground lead of the probe to earth ground only.
Do not apply a potential to any terminal, including the common terminal, that
exceeds the maximum rating of that terminal.
Do Not Operate Without Covers. Do not operate this product with covers or panels
removed.
Use Proper Fuse. Use only the fuse type and rating specified for this product.
Avoid Exposed Circuitry. Do not touch exposed connections and components
when power is present.
1705A Spectrum Monitor
Wear Eye Protection. Wear eye protection if exposure to high-intensity rays or
laser radiation exists.
Do Not Operate With Suspected Failures. If you suspect there is damage to this
product, have it inspected by qualified service personnel.
Do Not Operate in Wet/Damp Conditions.
Do Not Operate in an Explosive Atmosphere.
Keep Product Surfaces Clean and Dry.
ix
General Safety Summary
Provide Proper Ventilation. Refer to the manual’s installation instructions for
details on installing the product so it has proper ventilation.
Symbols and Terms
Terms in this Manual. These terms may appear in this manual:
WARNING. Warning statements identify conditions or practices that could result
in injury or loss of life.
CAUTION. Caution statements identify conditions or practices that could result in
damage to this product or other property.
Terms on the Product. These terms may appear on the product:
DANGER indicates an injury hazard immediately accessible as you read the
marking.
WARNING indicates an injury hazard not immediately accessible as you read the
marking.
CAUTION indicates a hazard to property including the product.
Symbols on the Product. The following symbols may appear on the product:
CAUTION
Refer to Manual
WARNING
High Voltage
Double
Insulated
Protective Ground
(Earth) Terminal
Not suitable for
connection to
the public telecom-
munications network
x
1705A Spectrum Monitor
Service Safety Summary
Only qualified personnel should perform service procedures. Read this Service
Safety Summary and the General Safety Summary before performing any service
procedures.
Do Not Service Alone. Do not perform internal service or adjustments of this
product unless another person capable of rendering first aid and resuscitation is
present.
Disconnect Power. To avoid electric shock, switch off the instrument power, then
disconnect the power cord from the mains power.
Use Caution When Servicing the CRT. To avoid electric shock or injury, use
extreme caution when handling the CRT. Only qualified personnel familiar with
CRT servicing procedures and precautions should remove or install the CRT.
CRTs retain hazardous voltages for long periods of time after power is turned off.
Before attempting any servicing, discharge the CRT by shorting the anode to
chassis ground. When discharging the CRT, connect the discharge path to ground
and then the anode. Rough handling may cause the CRT to implode. Do not nick
or scratch the glass or subject it to undue pressure when removing or installing it.
When handling the CRT, wear safety goggles and heavy gloves for protection.
Use Care When Servicing With Power On. Dangerous voltages or currents may
exist in this product. Disconnect power, remove battery (if applicable), and
disconnect test leads before removing protective panels, soldering, or replacing
components.
To avoid electric shock, do not touch exposed connections.
X-Radiation. To avoid x-radiation exposure, do not modify or otherwise alter the
high-voltage circuitry or the CRT enclosure. X-ray emissions generated within
this product have been sufficiently shielded.
1705A Spectrum Monitor
xi
Service Safety Summary
xii
1705A Spectrum Monitor
Preface
The information in this manual is intended for instrument operators and service
technicians. Operators are assumed to befamiliar with basic television terms and
measurements. Qualified service technicians are also assumed to be familiar with
television terms and measurements, and have moderate experience with analog
and logic circuits.
The manual is divided into two parts: Operator’s Information and Service
Information. The Operator’s Information is useful to both operators and service
technicians. The Service Information is intended only for qualified service
technicians.
Section 1, Introduction
Section 2, Operating
Instructions
Section 3, Installation
Section 4, Theory of
Operation
Section 5, Checks and
Adjustments
Section 1, Introduction, includes a general description of the instrument followed
by the Specifications. The Specifications include references to the corresponding Performance check steps.
Section 2, Operating Instructions, familiarizes the user with the front-- and
rear--panel controls, connectors, and indicators; includes an operator’s check-out
procedure; and includes other operator familiarization information.
Section 3, Installation, includes electrical and mechanical installation information. The electrical installation information includes adjustments and operational
changes available with the instrument. The mechanical installation information
includes rackmounting, custom installation, and portable use.
Section 4, Theory of Operation, provides an over-all block diagram description and
detailed circuit descriptions. Read the block diagram description for an overview of the
instrument. The detailed circuit descriptions should be used with the block diagram and
schematic diagrams in the foldout pages for specific information about individual
circuits.
Section 5, Checks and Adjustments, includes the Performance Check Procedure and the
Adjustment Procedure. The Performance Check Procedure is used to verify that the
instrument’s performance is within its specifications, and the Adjustment Procedure is
used to adjust the instrument to meet its specifications. The procedures are preceded by
a list of recommended test equipment. Each procedure has a short form listing of the
individual steps.
Section 6, Maintenance
1705A Spectrum Monitor
Section 6, Maintenance, includes preventive, troubleshooting, and corrective
information.
xiii
Preface
Section 7, Options
Section 8, Replaceable
Electrical Parts
Section 9, Diagrams
Section 10, Replaceable
Mechanical Parts
Section 7, Options, documents instrument options. The information in this
section summarizes the options. Additional details are included in appro-priate
places throughout the manual.
Section 8, Replaceable Electrical Parts, includes order information and part
numbers for all replaceable electrical parts.
Section 9, Diagrams, contains servicing illustra-tions. These include adjustment
locations, circuit board part locations, a block diagram, and schematic diagrams.
Parts locating tables are included that cross--reference the circuit board illustrations to the schematic diagrams.
Section 10, Replaceable Mechanical Parts, includes ordering information and
part numbers for all replaceable mechanical parts. This parts list is referenced to
an exploded view mechanical drawing. Also included are lists of accessories and
optional accessories.
xiv
1705A Spectrum Monitor
Contacting Tektronix
Preface
Phone 1-800-833-9200*
Address Tektronix, Inc.
Department or name (if known)
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
Web site www.tektronix.com
Sales support 1-800-833-9200, select option 1*
Service support 1-800-833-9200, select option 2*
Technical support Email: techsupport@tektronix.com
1-800-833-9200, select option 3*
6:00 a.m. -- 5:00 p.m. Pacific time
* This phone number is toll free in North America. After office hours, please leave a
voice mail message.
Outside North America, contact a Tektronix sales office or distributor; see the
Tektronix web site for a list of offices.
1705A Spectrum Monitor
xv
Preface
xvi
1705A Spectrum Monitor
Introduction
Section 1 Introduction
The TEKTRONIX 1705A Spectrum Monitor is an 8½” wide by 5¼” high
special purpose spectrum analyzer. It weighs approximately 8½ pounds and is
powered from an ac source. The crt occupies approximately two-thirds of the
front-panel area, with the control panel taking up the remainder of the space.
Operation is controlled by a microprocessor that polls the front-panel switches.
Front-panel switches are of the momentary touch type with lighted functional
indicators. In addition to polling the front panel, the microprocessor provides
the characters for an alphanumeric crt readout.
The signal is displayed on a bright crt. It is of the mesh type, for better
geometry, and uses an internal graticule to reduce parallax. Variable graticule
scale illumination provides even lighting over the usable graticule area to
improve measurement accuracy and the quality of display photographs.
The 1705A Spectrum Monitor is a swept front-end superheterodyne-type
spectrum analyzer with two inputs; L--Band to accommodate Low-Noise
Amplifier/Block Down Converter (LNB) outputs, and 70 MHz for use with
Video Exciters. The L--Band input (950 to 1800 MHz) is through an F-type
connector, while the 70 MHz input is through a standard bnc connector. The
L--BAND INPUT connector is the output for the selectable 18 V supply that is
the Block Down Converter auxiliary power.
Typical Configurations
1705A Spectrum Monitor
The TEKTRONIX 1705A Spectrum Monitor is designed primarily for use in
locating satellites and monitoring their signals. It is designed so that it can be
rack mounted, in a dual-width rack adapter, along with a half-rack waveform
monitor, such as a TEKTRONIX 1740-Series Waveform/Vector Monitor.
However, it can be used as a portable instrument. It is intended to be connected
to the rf feed with a directional connector. See Figure 1-1. It is capable of
providing the dc power required to run an LNB. The auxiliary LNB power is
turned on or off by a rear-panel slide switch. An indicator on the rear panel
lights when the +18 V supply is operating normally.
1- 1
Introduction
LOW-NOISE AMPLIFIER/
BLOCK DOWN CONVERTER
1705A
SPECTRUM MONITOR
Options
Accessories
Standard Accessories
RECEIVER
Figure 1-1: 1705A used to locate satellites and determine maximum signal level
The only options currently available for the 1705A Spectrum Monitor are the
power plug options described in Section 7 (Options). If no power cord options
are ordered, instruments are shipped with the North American 125 V power cord
and one replacement fuse.
1 Manual, Instruction
1 Adapter, F--type Male connector to BNC female connector
1 Power Cord, with the correct plug for the selected power plug option
1 Replacement Cartridge Fuse (correct rating for the power plug option)
1- 2
3 Replacement Scale Illumination Bulbs (Tektronix P/N 150-0168-00 or ANSI
#73)
1705A Spectrum Monitor
Introduction
Optional Accessories
Safety Information
Camera, C9 (Option 20)
Viewing Hood (016-0475-00)
Front Panel Cover (200-3897-01)
1700F00, Plain Cabinet (painted silver grey)
1700F02, Portable Cabinet (painted silver grey with handle, feet, and front
cover)
1700F05, Side-by-Side Rack Adapter
1700F06, Blank Half-Rack Width Panel
1700F07, Utility Drawer
The 1705A Spectrum Monitor is intended to operate from an ac power source
that will not apply more than 250 V rms between the supply conductors or
between either supply conductor and ground. A protective ground connection,
by way of the grounding conductor, is essential for safe operation.
The instrument was tested for compliance in a cabinet. To ensure continued
compliance, the instrument will need to be enclosed in a cabinet that is equivalent to those listed as Optional Accessories for the 1705A. A drawing of the
1700F00 plain cabinet is contained in the Installation Instructions (Section 3).
1705A Spectrum Monitor
1- 3
Introduction
ELECTRICAL SPECIFICATION
Table 1- 1: Spectrum Display
Performance
Characteristic
Frequency Range
L --- B a n d
70 MHz
Frequency Span
L --- B a n d
Full
10 MHz/Division
1 MHz/Division
100 kHz/Division
70
MHz
Full
1 MHz/Division
100 kHz/Division
Span/Div Accuracy Typically 0.5 minor Division.
Flatness L---Band ±5 dB.
Maximum Signal Input L --- B a n d : --- 3 0 d B m ,
Minimum Signal Input --- 8 0 d B m .
Relative Amplitude Accuracy L---Band (only)
Sweep Length
Sweep Speed Typically 20 --- 200 ms. 9
Positioning Range
Ver ti ca l
Horizontal
Displayed Frequencies in FULL
SPAN/DIV
L---BAND (900 --- 1900 MHz)
70 MHz (45 --- 100 MHz)
Frequency Readout Center Frequency shown by time
Requirements
950 to 1800 MHz
45 to 100 MHz
70 MHz ±2 dB.
75Ω.70MHz:
---20 dBm, 75Ω..
±3 dB/100 MHz.
+ and ---3 Divisions.
+ and ---2 Divisions.
Supplemental Information
F---type connector
Bnc connector
10 Horiz. Div. Equals:
1000 MHz
100 MHz
10 MHz
1MHz
10 Horiz. Div. Equals:
50 MHz
10 MHz
1MHz
Brightup offset by 1 Division in FULL
SPAN/DIV should still come on screen
in the next magnified position.
± from center (1400 MHz).
± from center (70 MHz).
Typically ±1 dB /100 MHz. 12
¶12 Divisions all SPANS/DIV settings.
Left Grat. Mid Grat. Right Grat.
Edge Line Edge
900 1400 1900
45 70 95
sharing graphic readout. Exact position on the trace of the center frequency shown by a caret in all spans except
FULL.
Check
Step
11
5
4, 5, 10, 11
11
12,
7
4
13
11
5
11
1- 4
1705A Spectrum Monitor
Table 1- 1: Spectrum Display (Cont.)
Introduction
Performance
Characteristic
Frequency Bright Up
Marker Registration
Readout Accuracy L---Band ±20 MHz.
Resolution
6dBDown
300 kHz
10 kHz
Video Filter
Low Noise Amplifier/Block Down
Converter dc Supply (LNB Power)
2 dB Gain Accuracy
Requirements
70 MHz ±2 MHz
+18 Vdc ±5%. 250
mA max.
¶2 dB/Division.
Supplemental Information
Full Span has bright up and frequency
readout (without cursor). Bright-up
area will be on screen in at least the
next narrower span.
Typically ±10 MHz.
Typically ±1 MHz.
300 kHz ±1 Division at 100 kHz
Span/Div.
<2 minor Divisions at 100 kHz Span/
Div.
Reduces Video bandwidth to ¶10 kHz.
Output through L---BAND input
connector, switched on and off by
rear-panel slide switch. LED indicator
on rear panel.
<3 dB/Division at ---50 dBm. 14
5
11
5
6
6
8
3
Check
Step
Table 1- 2: CRT Display
Performance
Characteristic
Crt Viewing Area 80 X 100 mm.
Accelerating Potential 13.75 kV.
Trace Rotation Range Greater than ±1˚
Graticule Internal 8 X 10 Division spectrum
Requirements
from horizontal.
Supplemental Information
Total adjustment range is typically 8˚.
analyzer graticule with variable SCALE
illumination.
Table 1- 3: Power Source
Performance
Characteristic
Mains Voltage Range 90---250 V. Continuous range from 90 to 250 Vac. 2
Mains Frequency Range 48 Hz to 66 Hz.
Power Consumption 35 Wa tts (120 BTU/HR) maximum.
Requirements
Supplemental Information
Check
Step
Check
Step
1705A Spectrum Monitor
1- 5
Introduction
Table 1- 4: Environmental Characteristics
Characteristic Supplemental Information
Temperature
Non-Operating
Operating
Altitude
Non-Operating
Operating
Vibration --- Operating 15 minutes each axis at 0.015”, frequency varied from 10---55---10 Hz in 1-minute
Shock --- Non-Operating 30 g’s, ½ sine, 11 ms duration, 3 shocks per surface (18 total).
Transportation Qualified under NTSC Test Procedure 1A, Category II (30” drop).
Humidity Will operate at 95% relative humidity for up to five days.
--- 5 5 ˚Cto+75˚C.
0˚Cto+50˚C.
To 50,000 feet (15,000 meters).
To 15,000 feet (4,800 meters).
cycles with instrument secured to vibration platform. Ten minutes each axis at
any resonant point or at 55 Hz if no resonant point is found.
Table 1- 5: Physical Characteristics
Characteristic Supplemental Information
Dimensions
Height
Widt h
Length
Weight Approximately 8.5 lbs (approximately 3.8 kg).
5 1/4 inches (133.4 mm).
8 1/2 inches (215.9 mm).
18 1/8 inches (460.4 mm).
Table 1- 6: Certifications and Compliances
EC Declaration of Conformity -EMC
Meets intent of Directive 89/336/EEC for Electromagnetic Compatibility. Compliance was
demonstrated to the following specifications as listed in the Official Journal of the European
Communities:
EN 50081-1 Emissions:
EN 55022 Class B Radiated and Conducted Emissions
EN 50082-1 Immunity:
IEC 801-2 Electrostatic Discharge Immunity
IEC 801-3 RF Electromagnetic Field Immunity
IEC 801-4 Electrical Fast Transient/Burst Immunity
High-quality shielded cables must be used to ensure compliance to the above listed standards.
This product complies when installed into any of the following Tektronix instrument enclosures:
1700F00 Standard Cabinet
1700F02 Portable Cabinet
1700F05 Rack Adapter
An increase of up to 20dB in the displayed noise floor may be observed if this instrument is
operated in electromagnetic fields of 3V/M or more, at frequencies of approximately 130, 250, 350,
or 490 MHz.
1- 6
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176 - FAX 781.665.0780 - TestEquipmentDepot.com
1705A Spectrum Monitor
Introduction
Table 1- 6: Certifications and Compliances (cont.)
FCC Compliance Emissions comply with FCC Code of Federal Regulations 47, Part 15, Subpart B, Class A Limits
Installation (Overvoltage)
Category
Pollution Degree A measure of the contaminates that could occur in the environment around and within a product.
Safety Standards
U.S. Nationally Recognized
Testing Laborat ory Listing
Canadian Certification CAN/CSA C22.2 No. 231 CSA safety requirements for electrical and electronic measuring and
European Union Compliance Low Voltage Directive 73/23/EEC, amended by 93/69/EEC
Terminals on this product may have different installation (overvoltage) category designations. The
installation categories are:
CAT III Distribution-level mains (usually permanently connected). Equipment at this level is
typically in a fixed industrial location.
CAT II Local-level mains (wall sockets). Equipment at this level includes appliances, portable
tools, and similar products. Equipment is usually cord-connected.
CAT I Secondary (signal level) or battery operated circuits of electronic equipment.
Typically the internal environment inside a product i s considered to be the same as the external.
Products should be used only in the environment for which they are rated.
Pollution Degree 1 No pollution or only dry, nonconductive pollution occurs. Products in
this category are generally encapsulated, hermetically sealed, or
located in clean rooms.
Pollution Degree 2
Pollution Degree 3
Pollution Degree 4
UL1244 Standard for electrical and electronic measuring and test equipment.
Normally only dry, nonconductive pollution occurs. Occasionally a
temporary conductivity that is caused by condensation must be
expected. This location is a typical office/home environment.
Temporary condensation occurs only when the product is out of
service.
Conductive pollution, or dry, nonconductive pollution that becomes
conductive due to condensation. These are sheltered locations where
neither temperature nor humidity is controlled. The area is protected
from direct sunshine, rain, or direct wind.
Pollution that generates persistent conductivity through conductive
dust, rain, or snow. Typical outdoor locations.
test equipment.
EN 61010-1 Safety requirements for electrical equipment for measurement,
control, and laboratory use.
Additional Compliance IEC61010-1 Safety requirements for electrical equipment for measurement,
control, and laboratory use.
1705A Spectrum Monitor
1- 7
Introduction
Table 1- 6: Certifications and Compliances (cont.)
Safety Certification Compliance
Temperature, operating +5 to +40_ C
Altitude (maximum operating) 2000 meters
Equipment Type Test and measuring
Safety Class Class 1 (as defined in IEC 1010-1, Annex H) -- grounded product
Overvoltage Category Overvoltage Category II (as defined in IEC 1010-1, Annex J)
Pollution Degree Pollution Degree 2 (as defined in IEC 1010-1). Note: Rated for indoor use only.
1- 8
1705A Spectrum Monitor
APPLICATIONS
Introduction
The principal application for the TEKTRONIX 1705A Spectrum Monitor is to
provide a convenient method to locate and identify Ku-Band satellites, find the
correct transponder and check on its availability, and optimize antenna positioning and polarization. The remainder of this section provides basic satellite
communications application data. Specific operating instructions are located in
Section 2, Operating Instructions.
Locating Satellites
The communications satellites that the television industry is interested in lie in a
band directly over the earth’s equator, at a distance of approximately 35,900 km
(or about 3.7 times the earth’s diameter). Traveling at approximately
11,000 km/h the satellite completes one full orbit in 23 hours, 56 minutes,
4.9 seconds, which is referred to as a sidereal day. When a satellite completes
one orbit in a sidereal day it is geographically stationary (geostationary) to a
point on the earth’s surface. Without being geostationary, using a satellite would
be extremely complicated and the calculations required to determine when they
were in the usable window, and how long they would stay there would, in most
cases, require a computer.
At 35,900 km distance the earth subtends an angle of 18˚, which provides
coverage of approximately 40% of the earth’s surface. See Figure 1-2. Forty
percent (40%) of the earth’s surface corresponds to an area stretching from 70˚
North latitude to 70˚ South latitude. For rough assumptions, a satellite, in
geostationary orbit over the equator, could cover latitudes from the Arctic circle
(66˚ 30’ N) to the Antarctic circle (66˚ 30’ S). However it should be noted that
even though the satellite is capable of covering 40% of the earth’s surface the
actual coverage will be less in most cases because of the antenna design and
available transmitter power.
70° N
1705A Spectrum Monitor
18°
70° S
35,900 km
Figure 1-2: Relationship of a communications satellite to earth
Determining the exact angle from the horizon to a satellite (other than at the
equator) requires a knowledge of trigonometry, because of the relatively close
9,675 km
1- 9
Introduction
orbit of the satellite. If the orbit of an equatorial orbiting satellite were roughly
equal to the distance from earth to the sun, ordinary latitude could be used to
determine the elevation of the antenna, which is, of necessity, very finely
focused. However since there is a disparity this angle is somewhat less than the
latitude for the earth station. See Figure 1-3. Simple logic readily points out
that as the latitude increases the angle from horizon to the satellite decreases. An
example of this would be that at 45˚ North or South latitude the angle above the
horizon is about 40˚ for a satellite at the earth station’s longitude. Figure 1-3
illustrates why it is not possible to pinpoint a satellite with ordinary navigation.
Satellite Footprints
SUN
A
SATELLITE
45° N
00°
(EQUATOR)
EARTH
Figure 1-3: Angle A (the difference at a specific latitude between the angle to the
sun and the angle to a satellite) is the reason ordinary navigation techniques
cannot be used to find a satellite
Figure 1-4 confirms that the angle from the prime meridian to a satellite will be
considerably different than the angle from a North American or European earth
station to the same satellite. It should also be noted that the elevation also
decreases for a satellite the further east or west from the earth station’s longitude.
Even though a satellite, in theory, can communicate with 40% of the earth’s
surface from its location, in most cases it will not. The antenna systems onboard
the satellites are usually designed to cover a specific area. These areas are
referred to as hemispheres, zones, and spots. A hemispherical beam is designed
to cover roughly 40% of the earth’s surface, for example, the western hemisphere. A zonal beam covers a specific area, for example, the Continental
United States, which is usually referred to as the CONUS beam. A spot beam is
exactly what it implies, concentrating on a smaller geographical area, such as the
western United States. With each of these beams there are areas where the signal
strength is greater. Figure 1-5 shows a propagation map for the western spot
beam for one Ku--Band satellite.
1- 10
1705A Spectrum Monitor
SPACENET 2
45°W
69°
RCA K2
81°
SBS 3
RCA K1
85°
97°
GSTAR A2
103°
ANIK C2
112.5°
GSTAR A1
105°
MORELOS 2
116.5°
ANIK B
109°
SBS 5
122°
MORELOS 1
113.5°
SPACENET 1
135°W
120°
ASC 1
128°
Introduction
PRIME MERIDIAN
000°
NORTH
POLE
90°E
CHICAGO
LOS ANGELES
ARCTIC
CIRCLE
ANCHORAGE
HONOLULU
INTERNATIONAL DATELINE
135°E
180°
45°E
GREENWICH
ENGLAND
NEW YORK CITY
Figure 1-4: Sample longitudinal map of the Ku-Band satellites of most interest to
news vehicle earth stations on the North American continent and Hawaii
Using the 1705A for Satellite Communication
The 1705A has two separate inputs, one, the L--Band Input, is specifically
designed to work with LNB down converters, which have an output signal range
of 0.95 to 1.80 GHz. This provides a means of looking at the signals from either
Ku or C--Band satellites. The second input is identified as 70 MHz and accepts
signals from 45 to 100 MHz. This second input is primarily designed to work
with the IF frequency of an exciter, but can also be used to look at signals in the
low VHF television band and the FM broadcast band up to 100 MHz.
1705A Spectrum Monitor
1- 11
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