Ailtech 7320, 7310 Service manual

OPERATION AND SERVICE MANU AL

----------

7310

73 20

SYSTEM N O I SE M 0N I T0RS

> 4I UECH

DIVISION CUTLER-HAMMER

WARRANTY

Except for tubes, fuses, and batteries which carry no warranty,
Cutler-Hammer, in connection with equipment sold, agrees to correct any
defect in workmanship or material which may develop during the period of
one year from the date of shipment under proper or normal use and not in
excess of the original manufacturer’s life expectancy ratings, by its option
to repair or replace, FOB point of shipment, the defective part or parts,
and such correction shall constitute a fulfillment of all Cutler-Hammer

liabilities in respect to said apparatus.

July 1978

Chapter I-General Information

1-1. Introduction 1-1
1-3. General Description 1-1
1-7. Safety Precautions 1-1
1-10. Technical Specifications • 1-1
1-12. Functional Description 1-5

1-13. General 1-5

1-15. The Noise Monitor in a Typical Application 1-5
1-17. Auxiliary Outputs 1-6
1-19. Options 1-6
1-21. Accessories 1-7

1-22. Noise Generators 1-7

1-23. Precision Attenuation 1-9

1-24. Test Equipment 1-10

Chapter II--Installation

TABLE OF CONTENTS

Page

2-1. Introduction 2-1
2-3. Unpacking, Inspection and Damage Claims 2-1
2-5. Ancillary Items 2-1
2-7. Rack Mounting 2-1
2-9. Preparation for Use 2-1

2-11. Initial Checkout 2-2

2-14. General 2-2

2-16. Checkout Procedures 2-2

Chapter Ill-Operating Instructions

3-1. General 3-1
3-3. Description of Operating Controls, Indicators and Connectors 3-1
3-5. Set-up Procedures 3-1
3-8. Interconnections " ' 3-1
3-17. Excess Noise Ratio Setting 3-5
3-21. Establishing the Correct Signal Levels 3-5
3-27. Operation 3-7

i

3-31. Use of Auxiliary Outputs 3-9

3-33. Signal Monitor, Jl, Pin 4 3-9
3-35. External Meter, Jl, Pins 6 and 7 3-9
3-37. Recorder Output, Jl, Pin 8 3-10

3-39. Manual Noise Figure (Temperature) Measurements . 3-10

Chapter IV-Theory of Operation

4-1. Introduction 4-1
4-3. General Theory 4-1

4-4. Noise Figure Theory 4-1
4-6. Noise Figure Measurement 4-2

4-8. Operating Noise Figure and Temperature Measurement 4-4
4-11. Functional Description (Automatic Noise Measurement) 4-5
4-15. Circuit Descriptions 4-8

4-17. IF Amplifier 4-9

4-22. Square Law Detector 4-9
4-24. Variable Gain Amplifier 4-9
4-25. Synchronous Integrator and Meter Amplifier 4-9
4-26. AGC Amplifier 4-9
4-31. Timing Signal Generator 4-10

4-39. Power Supply Board . 4-13

4-41. +12 Volt Regulator 4-14
4-42. -12 Volt Regulator 4-14
4-43> +28 Volt Noise Source Supply: 4-14

Page

Chapter V-Maintenance and Adjustments

5-1. General 5-1
5-3. Performance Verification 5-1

5-6. Minimum Operating Level 5-1
5-7. Noise Generator Power 5-2

5-8. Accuracy 5-2
5-10. Checks and Adjustments 5-3
5-13. Power Supply Adjustments 5-5
5-14. IF Adjustments 5-5

. 5-16. Preliminary 5-5

5-17. Procedure ' 5-6

ii

Page

5-18. Meter Adjustments 5-6
5-20. Auxiliary Output Adjustments 5-6

5-22. Signal Monitor 5-6

5-23. Recorder Output 5-7
5-24. Troubleshooting 5-7
5-26. General Information 5-7

5-27. Tools 5-7

5-28. Transistors 5-7

5-29. Integrated Circuits 5-8

5-30. Logic Family 5-8

5-31. Logic Circuits 5-8

5-32. Analog Gates 5-8

5-33. Operational Amplifiers 5-8

5-34. Printed Circuit Boards 5-8

5-37. Printed Circuit Board Connectors 5-8

5-38. Front Panel Lamps 5-13

5-39. ENR Thumbwheel Switch 5-14
5-40. Troubleshooting Procedures 5-14
5-44. Factory Service 5-14

Chapter VI--Spare Parts

6-1. General 6-1

6-2. Recommended Spare Parts 6-1
6-3. Replaceable Spare Parts 6-1

iii

LIST OF ILLUSTRATIONS

Figure
Frontis

piece
1-1
1-2 SNM, Models 7310 and Outline Dimensions
1-3 SNM, Models 7320 Outline Dimensions
1-4

1-5
1-6
1-7
1-8

3-1 7310/7320 SNM Control, Indicator, Connector Locations
3-2 Bench Measurement Set-ups
3-3

3-4 Illustration of Sensitivity and Signal Level Range
3-5 Location of the Manual-Auto Controls
3-6 AILTECH Noise Figure Slide Rule
3-7

System Noise Monitors 1-2

Typical Noise Figure Measurement Set-up Using the AILTECH

7300 System Noise Monitors
Layout of J1 1-6

Typical Noise Sources Used with the 7300 SNM’S

Maximum ENR vs Frequency 1-9

AILTECH 32 Precision Attenuator (Cased Version)

Typical “ Operating” Measurement Set-up

Nomograph for Determining Noise Figure or Temperature

Page

1-3
1-3

1-5

1-8

1-10

3-3

3-4
3-4
3-6

3-8

3-10
3-11

4-1 Equivalent Noise Representation of a Noisy Network 4-3
4-2
4-3 Equivalent Representation of an Operating Noise Measurement
4-4 Functional Block Diagram
4-5 Timing Signal Generator Simplified Schematic and Timing Diagram

5-1
5-2 Adjustment Locations 5-4
5-3 Plastic-Case Transistors 5-7
5-4

5-5 Integrated Circuits Functional Illustrations 5-11
5-6 3-Input NOR Gate Operation
5-7 Operation of the COS/MOS Bilateral Switch

5-8 Typical Applications of Operational Amplifiers

5-9
5-10 General Troubleshooting/Repair Flow Chart
5-11
5-12

Equivalent Representation of Noise Figure Measurement Set-up 4-3

4-4

4-5

4-11

Set-up for Checking SNM Accuracy

Integrated Circuit Case Styles

Pin Numbering Layout of a Typical AMP 87133 Connector

IF Troubleshooting Chart
AGC Troubleshooting Chart

5-3

5-9

5-12
5-12
5-13
5-13
5-15
5-17

5-18

iv

Figure

5-13 Video-DC Troubleshooting Chart 5-19

5-14 Timing Generator Troubleshooting Chart 5-20
5-15 Power Supply Troubleshooting Chart 5-21
5-16 Power Supply, Parts Location and Schematic Diagrams 5-22
5-17 IF-Video Parts Location and Schematic Diagrams 5-25
5-18 Wiring Diagram 5-27

LIST OF TABLES

Table Page

1-1 Technical Specifications 1-4
1-2 Applicable Noise Sources 1-7
1-3 Recommended Test Equipment 1-10

3-1 AILTECH 7310/7320 System Noise Monitors Controls,

Indicators and Connectors 3-2

4-1 Functional Illustration — Timing and Gating 4-8
4-2 3-Input NOR Circuit Truth Table 4-13

5-1 Test Equipment Required for Performance Verification 5-1
5-2 Power Supply Checks and Adjustments 5-5

v/ vi

CHAPTER I

GENERAL

1-1. INTRODUCTION

1-2. This Instruction Manual is for the AILTECH 7310 and AILTECH 7320 System Noise Mon
itors (SNM), figure 1-1, and contains physical and functional descriptions, installation and inspec
tion procedures, operating and maintenance instructions, and a parts list for each model. All
schematics, electrical and assembly drawings are included, as are appendices for the available option
al features. Unless otherwise stated, the information provided herein applies to both models.

1-3. GENERAL DESCRIPTION

1-4. The System Noise Monitors described in this Instruction Manual (7310 and 7320) are
functionally identical. Each provides a readout of the Noise Figure of a unit under test (UUT)
when connected in a valid measurement setup. The minimum test setup consists of a SNM, the
UUT, and a solid state noise source of the AILTECH 7600 series. The 7310 and 7320 have op
tional meter scales which provide an Operating Noise Temperature readout in lieu of Noise Figure.

1-5. The 7310 and 7320 SNM’s are referred to as analog units because the readout is by a meter
with two ranges. Range selection is made by means of a front panel switch. AILTECH also manu
factures the 7360 and 7370 which indicate Noise Figure by means of a three-digit LED display
and are generally referred to as digital units.

1-6. The 7310 (Figure 1-2) is 7V& inches wide and is intended for bench-top use while the 7320

(Figure 1-3) is approximately 17 inches wide and is intended for rack mounting. The optional
Rack Mount Angle Brackets (Option 11) must be attached for mounting in a standard 19 inch
rack.

1-7. SAFETY PRECAUTIONS

1-8. The SNM’s are a low power instrument but when the unit is opened for service, there is the
possibility of contacting the A.C. line. The potential hazard is reduced by covering all exposed >
contact points with insulating material. These instruments should be serviced by technically quali
fied personnel only.

1-9. A standard three-wire, polarized line cord is supplied with the instrument and mates with
an internationally accepted EMI/RFI line filter. The connector complies with all current and
proposed domestic and international requirements for commercial test equipment.

1-10. TECHNICAL SPECIFICATIONS

1-11. A listing of technical specifications is provided in Table 1-1. Outline illustrations for both
models are presented in Figure 1-2 and 1-3.

1- 1

a) AILTECH 7320

1- 2

b) AILTECH 7310

Figure 1-1 . System Noise Mon itor s'

T

5 V4'

Jl

I

13 1/4 '

14 7/8'

SIDE

-iJ-

Figure 1-2. SNM, Models 7310 and Outline Dimensions

17"

T

5 1/4"

Jl

Figure 1-3. SNM, Models 7320 Outline Dimensions

TABLE 1-1. TECHNICAL SPECIFICATIONS

Input Frequency ,

Bandwidth

Minimum Operating Level

(Note 1)

Signal Level Range (Note 2)

Input Impedance

Accuracy (Note 3)

Meter Ranges

10.7, 21.4, 30, |36,¡45, 60 or 70 MHz
(to be specified at time of order)

10% of center frequency (nominal)

Less than -70 dBm

40 dB (minimum)

50 ohms (nominal); 75 ohms, optional if
specified at time of order.

Full scale to half scale:

±0.25 dB (Noise Figure)
±5% (Noise Temperature)

Half scale to quarter scale:

±0.5 dB (Noise Figure)
±8% (Noise Temperature)

0 and 6 dB full scale (Noise Figure),
60 and 240 kelvins full scale (Noise
Temperature). Extension to infinity
on all scales. »

Excess Noise Ratio

Calibration Range

Noise Generator Power

Recorder Output

Auxiliary Output Connector

(Recorder, Signal Monitor
and All Options)

Input Power

Dimensions

7310

7320

6 to 15.9 dB

Sufficient to drive all AILTECH Series 76
Solid-State Noise Sources

1 volt across IK ohms nominal for full
scale meter deflection.

Amphenol 57-20240-1, mates with
Amphenol 57-30240 supplied with unit
(see para. 1-17).

115/230 VAC ±15%, 50-400 Hz, 10 Watts

5 1/4”H x 7 7/16”W x 13 1/4”D (less
handles)(13.3 x 18.9 x 34.3 cm)

5 1/4”H x 17”W x 13 1/4”D (less handles)
(13.3 x 43.2 x 34.3 cm)
See Figures 1-2 and 1-3.

TABLE 1-1. TECHNICAL SPECIFICATIONS (continued)

Weight

7310 10 lbs. Net (4.5 kg)

7320 15 lbs. Net (6.8 kg)

NOTES:

1. Lowest noise input level (noise source off), at which valid automatic measurements
may be performed.

2. Range of noise levels (including Y-factor) over which valid measurements may be
performed.

3. Accuracy in the automatic mode is defined as the maximum permissible deviation from
a manual measurement made under the same conditions.

1-12. FUNCTIONAL DESCRIPTION

1-13. General

14 lbs. Shipped (6.3 kg)

19 lbs. Shipped (8.6 kg)

1-14. The System Noise Monitors are designed for both field and production applications where

simplicity and high accuracy instrumentation are required. The SNM’s are capable of providing fully
automatic testing via a continuous indication of noise performance for a variety of components,
assemblies and receivers. Simplified functional operation of the SNM’s is described in the typical
applications presented in the following paragraphs; a detailed functional description is provided in
Section IV. All AILTECH solid state noise sources from 10 MHz to 18 GHz are usable with the
SNM’s described herein (see paragraph 1-23).

1-15. The System Noise Monitor in a Typical Application

1-16. In a typical measurement set-up for transistors, amplifiers, mixers, receivers, etc. such as
that shown in Figure 1-4, the SNM furnishes modulated low level DC power to the noise source,
which in turn provides alternating noise-on and noise-off periods to the unit under test (UUT).

Figure 1-4. Typical Noise Figure Measurement Set-up Using

the AILTECH 7300 System Noise Monitors

1 - 5

An intermediate frequency (IF) is derived either internal to the UUT in the case of a complete
transceiver or externally by means of added downconverters. This signal, which consists of periods
of IF noise from the UUT alone, alternating with periods of UUT noise plus that added by the
noise source, is applied to the SNM input. The difference between the two detected levels derived
from the IF signal is related to the noise performance of the UUT. This difference is synchro
nously detected and displayed directly as noise figure or noise temperature by the SNM.

1-17. AUXILIARY OUTPUTS

1-18. Several auxiliary outputs for remote monitoring or record keeping are available at Jl, a
multipin connector on the rear panel. The layout of Jl is shown in Figure 1-5. The outputs
available are as follows:

a. Alarm Relay. An optional (Option 03) variable threshold alarm relay, applicable to

all models.

b. Signal Monitor. A DC signal that varies from 0 to 6 volts (nominal) as the input IF

level increases from the sensitivity limit to 50 dB above that limit. This is a non
linear output intended only to indicate signal level.

c. External Meter. A meter with 100 microamps full-scale sensitivity connected across

pins 6 and 7 of Jl will track the excursion of the SNM front-panel meter. When
Option 12, 10 volt recorder output, is installed the External Meter Function is not
available.

d. Recorder Output. One volt into 1 K ohm for full scale deflection of the front panel

meter.

J1

O O

o o

O 0
o o
o o
o o
O 0

O 0
o o
o o
O 0

13 ^

......

►

— b

— ►

1— ►

— »

— ^

24

• I
>

NOT USED

OPTIONAL

ALARM RELAY

SIGNAL MONITOR

SIGNAL GND

EXT. METER (-)

EXT. METER (+)

RECORDER OUTPUT

NOT USED

1

SW
NO

« - O 0

NC

4 —

•4—
< #-

4 —

12

Figure 1-5. Layout of Jl

1-19. OPTIONS

1-20. The following options are available for the 7300 System Noise Monitors and are listed here
for reference and identification purposes. See the referenced appendices or documents for com
plete option descriptions. .

1- 6

a. Option 02, Radar Noise Monitor. Applicable to the 7320 SNM only. Provides for

continuous, on-line, noise performance monitoring of an operating radar without

interfering with the radar operation. Option 02 is covered in a separate manual.

b. Option 03, Alarm Indication. Applicable to both models. SPDT relay deenergizes

when the measured noise figure degrades beyond a preset limit. The threshold is
continuously variable from inside the unit. The relay contacts are available at J1
(see Figure 1-5). Refer to Appendix B.

c. Option 06, Special Paint. Applicable to both models. Front panels can be painted in

accordance to customer’s specifications (with customer supplied paint).

d. Option 07, High Sensitivity. Applicable to the 7320 SNM only. Improves the sensi

tivity to -100 dBm. Refer to Appendix C.

e. Option 09, Broadband Mixer Input. Available on 7320 SNM only. Addition of a

broadband, mixer with all ports (RF, LO, IF) available at the rear panel. The mixer
cover 10 to 1,000 MHz. Refer to Appendix D.

f. Option 10, Front Panel Controls for Manual Operation. Applicable to both models.

The controls required for manual Y-factor measurement are moved to the front panel.
Refer to Appendix E.

g. Option 11, Rack Adaptor Brackets. Applicable to the 7320 SNM only. Permits

mating the front panel with a standard 19 inch rack. See Appendix F.

1-21. ACCESSORIES

1-22. Noise Generators. A complete measurement setup requires a noise generator in addition to

the SNM. All 7300 SNM’s are designed to operate with solid-state noise sources of the 7600 series.

Table 1-2 lists the applicable sources and Figure 1-6 illustrates some typical noise generators.

TABLE 1-2. APPLICABLE NOISE SOURCES

Part Number 07615 07616

Frequency Range

(GHz)

Excess Noise Ratio

(dB)

Calibration Freq.

(GHz)

ENR Accuracy (3) (dB)

VSWR (maximum) 1.2 1.2

0.01-1.5 1-12.4 12.4-18

15.5±0.5

0.03, 0.3,

1.0,1.5

±0.3 ±0.3 ±0.25

15.5±0.5 15.5±1

1,2,3.95,

8.2, 12.4

07617

12.4,15,18,

1.3

7650-X (1) 7660-X (1)

(2) (2)

see
figure 1-7

3 points specified at
time of order

±0.5(4)

4:1

see
figure 1-7

±0.5(4)

4:1

Output Connector

N male

N male

Table continued on page 1-8

OSM female Type N-male

OSM-female

1 -7

TABLE 1-2. APPLICABLE NOISE SOURCES (Continued)
Part Number
Input Connector BNC female
Input Requirements 28 volts at

07615 07616 07617

less than

30 mA

BNC female
28 volts at

less than
30 mA

BNC female
28 volts at

less than
30 mA

7650-X (1) 7660-X (1)
BNC female BNC female

28.0 V at
30 mA
maximum

28.0 V at
30 mA
maximum

NOTES:

1. Last digit assigned to each specific noise source at time of order.

2. Up to 15% of the center frequency from 10 MHz to 18 GHz — wider bandwidths available.

3. Accuracy of the ENR data supplied at the calibration frequencies.

4. Higher accuracy available.

a) 07615 10 to 1500 MHz

b) 07616 1 to 12.4 GHz

. S/M 2 0 9 ,

BIAS 28.00 VDC

’u r n NOISE GENÉ51Ï * *

c) 07617 12.4 to 18 GHz

d) 07660 Typical High Level System Noise Source

Figure 1-6. Typical Noise Sources Used With the 7300 SNM’s

1- 8

40

Figure 1-7. Maximum ENR vs Frequency

1-23. Precision Attenuation. The AILTECH 32 Series Precision Attenuators are tuned, contin
uously variable attenuators which provide an accurate means of measuring Y -factor. These instru
ments are necessary for routine, periodic recalibration of the 7300 System Noise Monitors. How
ever, for critical applications where it is desired to improve precision by recalibrating on-line on a
short term basis, the Precision Attenuator becomes a valuable adjunct to the measurement setup.
These attentuators (see Figure 1-8) are available at common intermediate frequencies in rack mount,
cased, and unmounted configurations.

1- 9

Figure 1-8. AILTECH 32 Precision Attenuator (Cased Version)

1-24. TEST EQUIPMENT

1-25. Table 1-3 lists the test equipment recommended for use in testing, adjusting and servicing

SNM’s.

TABLE 1-3. RECOMMENDED TEST EQUIPMENT

Description

Precision Attenuator

Signal Generator

Digital Multimeter

Vector Voltmeter

Oscilloscope

Noise Generator

Amplifier

1-10

Specification

IF equal to 7 300

Calibrated output from

-100 to -30 dBm at 7300 IF

4V2 digits

10 to 100 MHz

200 MHz 3 dB BW

Compatible with UUT and SNM

Compatible with Noise Generator
and SNM

Recommended Model

AILTECH 32 Series

Boonton 512

Systron-Donner 7004A

PRD 2020

Tektronix 475

AILTECH 76 Series

(Simulates UUT).

CHAPTER II

INSTALLATION

2-1. INTRODUCTION

2-2. This chapter describes unpacking, inspection, preparation for use and initial checkout of

the AILTECH 7300 Series System Noise Monitors.

2-3. UNPACKING, INSPECTION AND DAMAGE CLAIMS

2-4. No special instructions or precautions are necessary for unpacking the SNM; the instrument
is ready for use immediately upon receipt. The following checks should be made to assure that no
damage has occurred during shipment.

a. Inspect the shipping container prior to acceptance from the carrier. Note any damage

to the shipping container on the carrier’s receipt.

b. Inspect the instrument for damage. Check for dents, scratches, broken switches, con

nectors, etc.

c. Remove the top and bottom covers and inspect for broken components or loose

hardware.

d. If damage is not apparent until after the instrument has been accepted, file a claim for

concealed damage with the carrier within 15 days after receipt. All packaging material
must be kept for inspection by the carrier’s agent. A copy of the claim must be for
warded to AILTECH.

2-5. ANCILLARY ITEMS
2-6. Each SNM is accompanied by a mating line cord, a mating plug for the auxiliary output con

nector, and one instruction manual. Before discarding the shipping container, make certain these

items are removed.

2-7. RACK MOUNTING

2-8. Rack Mounting Adapter Kit, Option 11 is required to secure the AILTECH 7320 in a
standard 19 inch rack. The kit consists of two right angle brackets which bolt to the side of the

unit. Complete assembly instructions are provided with the kit.

2-9. PREPARATION FOR USE

2-10. Prior to shipment from the factory, the internal mode switches of the System Noise Monitor
are set for normal automatic noise figure (or temperature) measurements, and the line voltage
switch on the rear panel is set to the value appropriate for the shipping destination. However, it is
good practice to check these settings prior to operating the instrument as follows:

. a. Note the setting of the rear panel line voltage switch. Set it to 115 or 230 volts AC

as required (see Figure 3-1).

2 -1

b. Check both line fuses, F I and F2, and make certain they are the correct value for the

line voltage selected:

230 VAC: FI, F2 = 1/8 Amp.

115 VAC: FI, F2 = 1/4 Amp.

c. Remove the single Phillips-head screw holding the top cover in place, and remove the

top cover.

d. See Figure 3-5 for the location of the IF-Video board and for the locations of the MAN-

AUTO and noise generator ON-OFF switches on the IF-Video board.

e. Make certain that the MAN-AUTO switch is in the AUTO position and the noise

generator ON-OFF switch is in the OFF position.

2-11. INITIAL CHECKOUT

2-12. This operational checkout is a preliminary test and is not intended to validate performance
standards. (For complete Validation Procedure, refer to Chapter V.) Figure 3-1 and Table 3-1
locate and describe the function of the controls, indicators and connectors referenced below.

2-13. The equipment required for initial operational checkout is as follows:

a. Oscilloscope — Tektronix 475 (or equivalent).

b. Signal Generator — Boonton Model 102A (or equivalent).

c. Digital Multimeter — SystonDonner 7004A.

2-14. General

2-15. Perform the procedures detailed under paragraph 2-10. Connect the line cord to the appro
priate AC power source. '

CAUTION

The 7300 System Noise Monitors are low power instruments, but routine

precautions should be observed due to the possibility of contact with the
applied AC line.

2-16. Checkout procedures

a. With the power ON-OFF switch in the OFF position and the instrument in its normal

operating orientation, note the reading of the front panel meter. If it indicates
infinity (°°) proceed to step (b). If it does not indicate infinity, adjust the meter as
follows:

2- 2

1. Locate the zero adjustment screw at the rear of the meter case, between and just
below the terminals.

2. Rotate the screw until the meter reads up-scale (lower noise figures).

3. Continue rotating the screw in the same direction until the needle again indicates
infinity.

b. Set the power ON-OFF switch to the ON position, allow a few minutes for stabiliza

tion, and note that:

1. The red power indicator is illuminated.

2. The green SIGNAL LEVEL indicator is not illuminated.

c. Set the RANGE switch on the front panel to the HIGH position. Note that the meter

still indicates infinity.

d. Connect the output of the signal generator to the IF input. Set the output frequency

to the center frequency of the SNM. Set the output level to rated sensitivity of the
SNM:

-70 dBm for standard units

-100 dBm for units equipped with Option -07, High Sensitivity.

Note that the green SIGNAL LEVEL lamp is illuminated.

e. Locate the MAN-AUTO switch on the IF-Video board and set it to the MAN position.

Note that the green SIGNAL LEVEL lamp extinguishes.

f. Set the front panel RANGE switch to the LOW position. Adjust the signal generator

output level for full-scale indication (0 dB or 60K). Adjust the internal MAN GAIN *
control counterclockwise for a quarter-scale indication (6 dB or 240K).

g. Set the front panel RANGE switch to the HIGH position. Note that the indication

rises to approximately full-scale (± 2 dB).

h. Connect the multimeter, set up to read +28 volts DC, to the BNC connector on the

rear panel marked NOISE SOURCE. Note that the multimeter reads 0 ± 0.5 volts.

i. Set the noise generator ON-OFF^witch on the IF video board to ON. Note that the

multimeter reads +28.00 ±0.05 volts.

j. Disconnect the multimeter. Set the noise generator ON-OFF and MAN-AUTO

switches on the IF-Video board to OFF and AUTO respectively. Connect the oscil
loscope to the NOISE SOURCE BNC connector on the rear panel. Note that the
output is a rectangular, positive pulse, alternating between 0 and +28 volts, at about
a 285 Hz rate).

k. Disconnect the oscilloscope, and replace the top cover.

* These controls are on the front panel of those units equipped with Option 10.

NOTE

If the instrument fails any portion of the checkout procedure, it requires
adjustment or repair. Refer to Chapter V for adjustment and troubleshooting
instructions. If the unit is still under warranty, contact your local AILTECH
representative. .

2- 3 /2 - 4

CHAPTER III

OPERATING INSTRUCTIONS

3-1. GENERAL

3-2. This chapter provides a description of the SNM operating controls, indicators and connectors
and typical SNM operating procedures.

3-3. DESCRIPTION OF OPERATING CONTROLS, INDICATORS AND CONNECTORS.

3-4. The front and rear panel controls, indicators and connectors for SNM Models 7310/7320
are listed in Table 3-1 and illustrated in Figure 3-1. The functions of the controls, indicators and
connectors for Models 7310 and 7320 are identical.

3-5. SET-UP PROCEDURES
3-6. The AILTECH 7300 System Noise Monitors are normally applied to the continuous or peri

odic measurement of a single receiving system, or repeated measurements of similar types o f.
devices (as on a production line test station). Therefore, some care should be exercised in setting
up the measurement system to insure the validity of the indicated results.

3-7. There are three major factors to be considered in setting up the measurement system:

a. Interconnections.

b. Establishment of the correct Excess Noise Ratio (ENR) setting for the front panel

thumbwheel switch on the SNM.

c. Establishment of signal levels within the measurement range of the SNM.

3-8. Interconnections

3-9. In general, there are two types of set-ups for noise parameter measurements. For purposes
of identification these will be referred to as “ bench” and “ operating” noise measurements.

3-10. Most true noise figure measurement are of the bench type. In this case, the setup will be as

indicated in Figure 3-2.

3-11. If the noise source is a typical laboratory noise generator with an excess noise ratio (ENR)
less than 16 dB — such as the AILTECH 7615, 7616, and 7617 Noise Generators — it can be con
nected directly to the input of the unit-under-test (UUT). .

3-12. If the noise source is a high-level unit with an ENR greater than 16 dB — such as most units

in the 7650, 7660 series — a calibrated attenuator sufficient to reduce the ENR to a value between

6 and 15.9 dB must be inserted between the noise source and the input of the UUT (effective ENR

is the noise source ENR less the attenuation in dB).

3-13. Operating measurements are those made with the receiver connected in its normal operating
environment. In most cases, this means the input connected to an antenna. Noise is injected into
the system by means of a directional coupler (see Figure 3-3). This setup usually requires a high
level noise source, such as the AILTECH 7650 or 7660.

3- 1

TABLE 3-1. AILTECH 7310/7320 SYSTEM NOISE MONITORS CONTROLS, INDICATORS

AND CONNECTORS

Key

(Figure 3-1)

1

2

3

4

5

5a

6

7

Reference

Title

ON OFF

SYSTEM ENR (dB)

SIGNAL LEVEL

NOISE FIGURE (dB)

NOISE TEMPERA
TURE—Kelvins

RANGE LOW/HIGH S2

Fuse

Designation

DL1

SI

S3

DL2 Green indicator is illuminated when the

MI Indicates Noise Figure.

MI Alternate meter scale indicates

FI Line fuse.

Function

Red indicator is illuminated when AC
power is applied.

Lever switch controls application of AC
power.

Thumbwheel switch calibrates SNM for
selected excess noise ratio.

input IF level exceeds some arbitrary
minimum.

Operating Noise Temperature.

Rocker switch selects meter range.

10

11

12

13

8

9

Fuse

LINE

AC INPUT

Connector

IF INPUT

NOISE SOURCE J9

F2 Line fuse.

S ll

—.

J1

J8

Slide switch selects primary AC input
line voltage.

Recessed plug for application of
primary AC input.

Multipin connector (Amphenol 57

20240-1, mate supplied) for auxiliary
outputs (see paragraph 1-17).

BNC female connector for application
of IF signal from unit under test.

BNC female connector provides exci
tation for the AILTECH Series 7600
Noise Source.

3-2

11

3-3

RF

NOISE*
GENERATOR

*TYPICAL MODELS - 7615, 7616, 7617

INPUT

]

(a) Set-up for Bench Measurements Using Noise Sources

With ENR’s Between 6.0 and 15.9 dB

DEVICE
UNDER

TEST

IF

OUTPUT

IF

INPUT

(J8-REAR

PANEL)

(J7-REAR

PAN ELI

NOISE
SOURCE

(b) Set-up for Bench Measurements Using High-Level Noise Sources

Figure 3-2. Bench Measurement Set-ups

Figure 3-3. Typical “ Operating” Measurement Set-up

3 -4

3-14. The measurement performed by a setup such as that illustrated in Figure 3-3 is often

called Operating Noise Figure. This is a noise figure measurement in which the cold noise tempera
ture is that of the actual operating termination, but the results are displayed as though the termina
tion was at the standard reference temperature, 290 kelvins. In general, this measurement will yield

lower noise figure readings than a true noise figure measurement (assuming a quality antenna with
an effective noise temperature less than 290K). This type of measurement is quite commonly made
on radar receivers, and is sometimes called radar noise figure.

3-15. If the SNM readout is in noise temperature, then the measured parameter is Operating Noise
Temperature. This parameter is often measured on high-sensitivity, long range receivers, such as
satellite earth stations.

3-16. Other factors to be considered are:

a. Frequency compatibility between the noise source and the RF input of the UUT (a

matter of proper noise source selection).

b. Frequency compatibility between the IF output of the UUT and the System Noise

Monitor. This may require frequency conversion (see paragraph 1-19 for options
which provide this feature).

3-17. Excess Noise Ratio Setting

3-18. The accuracy of the 7300 SNM depends upon accurate setting of the front panel ENR
thumbwheel switch. Any error in this switch setting is translated directly — dB for dB — to the
noise figure indication.

3-19. Laboratory or bench-type noise generators such as the AILTECH 7615, 7616, and 7617 (see
Figure 1-6) have an ENR vs. frequency calibration chart attached or printed on the generator body
and are accompanied by a record of calibration. System noise sources, such as the 7650 and 7660
are also accompanied by calibration records.

3-20. To determine the ENR thumbwheel settings:

a. Locate the two frequencies on the noise source calibration record (or calibration

chart) that straddle the RF input frequency of the UUT (assuming the input frequency
does not coincide with a calibration point).

b. Use straight line interpolation to determine the basic noise source ENR.

c. If the set-up is as shown in Figure 3-2(a), adjust the ENR thumbwheel to the result in

(b) to the nearest 0.1 dB.

d. If the set-up is as shown in Figure 3-2(b), subtract the attenuation (in dB) from the

ENR determined in (b). Adjust the ENR thumbwheel to the resulting difference to
the nearest 0.1 dB.

3-21. Establishing the Correct Signal Levels

3-22. The basic sensitivity (low point of the valid signal level range) of the 7300 System Noise
Monitors is better than -7 0 dBm. This is not the point at which the green Signal Level light comes
on. This light is meant only as a gross indication that some signal is available from the UUT.

3-5

3-23. To determine sensitivity or low end of the signal level range a signal generator to provide
low level signals at the SNM center frequency is required (a typical unit is the Boonton 102A).

a. Make certain the SNM is in the AUTO mode (S101).

b. Connect a signal generator tuned to the center frequency of the SNM to the IF Input.

c. Gradually increase the signal generator output level from about -85 dBm until the

green Signal Level light illuminates. Note the generator output level.

d. Increase the generator output 5 dB above the point where the Signal Level light comes

on. This is the sensitivity or lower end of the valid signal level range. Note that this

level is less than -70 dBm, and record it for future reference.

NOTE

If a continuous indication of signal level is desired, see Paragraph 3-33.

3-24. The upper end of the valid signal level range will be 40 dB above the sensitivity as deter
mined from paragraph 3-23 (d). All signals — both with the noise source on and the noise source
off — must remain within this range. Figure 3-4 illustrates this range using typical levels.

UPPER L IM IT -3 3 dBm*

LU'
>

LU

_ l

_l

<

z

C/3

-40 dBm —

-50 dBm —

-60 dBm

-70 dBm

-80 dBm

Y

FACTOR

SENSITIVITY -73 dBm*

SIGNAL LEVEL LIGHT -78 dBm*

*Typical Values

3- 6

Figure 34. Illustration of Sensitivity and Signal Level Range

3-25. To insure that the UUT output is within the valid range, proceed as follows:

a. Remove the top cover of the SNM and locate the following controls on the IF-Video

board (see Figure 3-5). These controls are on the front panel of those units equipped

with Option 10, Manual Front Panel Controls:

MAN-AUTO switch, S101

MANUAL GAIN control, R140

Noise Generator ON-OFF Switch, S102 .

b. Connect a signal generator tuned to the SNM center frequency and set the output level

as described in paragraph 3-23 (d).

c. Set the following controls as indicated:

1. Front panel RANGE switch to LOW

2. MAN-AUTO switch S101 to MAN

3. Noise Generator switch S102 to OFF

d. Adjust manual GAIN control, R140, for a convenient on-scale reading at the upper

50% of the scale. Record the setting.

e. Without disturbing the preceding settings, disconnect the signal generator and set up

the measurement system in accordance with Figure 3-2 or 3-3 as required.

f. If the noise figure indication with the control settings as above is higher (down-scale)

than (d), additional gain is required between the UUT and the SNM input. Add gain
as required (or see paragraph 1-19 for an option to provide better sensitivity) to bring
the reading lower in noise figure or temperature than (d) and proceed to (h).

. g. If the indication is a lower noise figure than (d), or off-scale to the right, set Noise

Generator switch S I02 to ON.

h. Add attenuation at the SNM input until the indication returns to (d). If the total

attenuation required is greater than 40 dB, there is too much gain in the UUT, and
fixed attenuation must be provided at the SNM input as part of the set-up.

3-26. After establishing the correct input levels, set MAN-AUTO switch S101 to AUTO and Noise

generator switch S102 to OFF. Replace the top cover.

3-27. OPERATION

3-28. Once set-up is accomplished, the ENR switch correctly set, and the correct signal levels
established, the System Noise Monitor will automatically indicate noise figure or noise temperature.
No further operator activity is required other than setting the RANGE switch for optimum resolu
tion as noted below.

3-29. The AILTECH 7310 and 7320 Analog System Noise Monitors have two noise figure ranges
with 0 and 6 dB at full scale. Increasing noise figure causes the meter to read down-scale. If the
UUT noise figure is less than 6 dB, set the front panel RANGE switch to the LOW position and
read noise figure. If the noise figure is greater than 6 dB set the switch to the HIGH position and
read the noise figure.

5101

MAN-AUTO

SWITCH

5102

MANUAL

ON-ÓFF
SWITCH

O' Uif

1 = 3 0 1 = 1

POWER SUPPLY

PC BOARD ASSEMBLY

298021-1

IF-VIDEO PC

BOARD ASSEMBLY

298020

-1 10 TO 40 MHz

-2 40 TO 70 MHz

3- 8

R140

MANUAL

GAIN

m&\p

ENR PC BOARD

ASSEMBLY

298172

S3

ENR SWITCH

Figure 3-5. Location of the Manual-Auto Controls

3-30. Those System Noise Monitors with the symbol (T) in their part numbers are equipped with
operating noise temperature scales. These also have two ranges, and the full-scale values are 60
and 240 kelvins.

3-31. USE OF AUXILIARY OUTPUTS

3-32. Paragraph 1-17 briefly described several auxiliary outputs available at J1 on the rear panel.

These outputs may be used for monitoring signal level, for permanent records of noise figure (or
temperature) variations with time, and for providing a readout at a remote location.

3-33. Signal Monitor, Jl, Pin 4 (see Figure 1-5 for layout of Jl). This output provides a DC

signal that varies from near zero to approximately 6 volts as the input signal level increases by
about 40 dB from the sensitivity limit. It is a non-linear, uncalibrated output; however, it can be
very useful for insuring that the UUT output level remains in the valid range as established by
paragraph 3-25. This can be accomplished as follows:

a. Connect a voltmeter, 0 to +10 volts DC capability between Jl-4(+) and Jl-5 (-, GND).

b. Proceed as indicated in Paragraph 3-23.

c. Record the voltmeter indication upon completion of paragraph 3-23 (d). This indica

tion corresponds to signal level at the low-limit of the valid range.

d. Increase the signal level by 40 dB, less the expected Y-factor (see paragraph 3-34).

Record the voltmeter indication which will represent the maximum permissible signal
level.

3-34. When operating the SNM in the AUTO mode, the signal levels are valid as long as the volt

meter remains within the limits established in paragraph 3-33 (c) and (d).

NOTE

The expected Y -factor is a function of the noise figure of the UUT and
the effective ENR. For noise figures less than 6 dB and ENR’s greater
than 14 dB, the expected Y-factor can be approximated by subtracting
noise figure from ENR (both quantities in dB). For other situations it
may be calculated from:

(3-1)

where ENR and F are expressed as power ratios.

It may also be determined from the AILTECH Noise Figure Slide Rule,
Figure 3-6, or the nomograph of Figure 3-7.

3-35. External Meter, Jl, Pins 6 and 7. This feature provides for a readout of noise figure at a
remote location. Any 100 microamp, IK ohm full scale meter connected across the referenced
pins (+ to pin 7; - to pin 6) will track the excursions of the front panel meter. A duplicate of the
front panel meter complete with scaling is available for this purpose.

3-36. The external meter leads are ungrounded and should be twisted and shielded for runs of
more than one foot.

3 - 9

r

| T ! i | f j i | i | 1 1 1 1 1 1 i ) i | i i i i | i i i i | i i i i | ! i i i j 1 1 1 1 1 1 1 >1 1 r 111 |i ii i[ ii ii | •

TECH

A CUTLER-HAMMER COMPANY

500 2000 3000 4000 500 0 6000 800 01 0.00
)7 -106 105 104 - 1 0 3 -1 0 2 • 101 - 100

99 EQU IV ALENT INPUT
iilimlii NOISE POWER dBm

'S

2 3 4 5 6 7 8 9 10 11 12

-1 1 2 - 1 1 0 -1 0 8 - 106 -1 0 4 - 1 0 2

100 200 300 400 600 800 1000 1500 2000 3000 4000

ii!iiit!ii!iliM i!i|iilMiili!iiliiiil¡iiiliii[liiiiE 1111 ¡i 11 il m il i r ii l i m l i i

i!l!l|lli!|llll|ll!l|[ill|lill|iill|llll|l|ll|llll...............................

10 9 8 7 6

LOSS CORRECTION (dB)

NOISE

SLIDE-RULE

ijim

5

4 3 2

20 19 la

10 9 8
? .8 .? .6 .5 .4

11 I I I I

13 14

- 10 0

60.00 8000

.....

........

Ü>

14 13 12 11 10

FdB

15

dBm /M Hi

Te KELVINS

llllllllllllllllillllllllllllijllllllllll

iil|iiii|iiii|iiii|i h 111

4 3 2

ENR (dB)

Yds for Tco id = T0

NOISE OENER ATORS

Yds (or HOT and COLD

NOISE GENERATORS

(

Figure 3-6. AILTEGH Noise Figure Slide Rule

3-37. Recorder Output, Jl, Pin 8. This output is a voltage referenced to ground (pin 5) that
tracks the meter excursions. It will provide approximately 1 volt across IK ohm for full scale
deflection of the meter. This feature is necessary in evaluating noise performance excursions with
time, investigating suspected intermittents in a receiver system, and providing hard copy for swept

measurement systems.

3-38. The recording device will require calibration. This can be done in the Manual mode by ap
plying a CW signal from a generator to the IF input, and marking the recorder position for various

meter indications. This calibration will remain valid when the SNM is switched back to the Auto
mode. '

3-39. MANUAL NOISE FIGURE (TEMPERATURE) MEASUREMENTS

3-40. All AILTECH 7300 Series System Noise Monitors include a manual mode of operation. In

this mode, the noise source can be turned on or off under operator control (rather than auto

matically switched), and the internal automatic control circuits are disabled. The instrument then

provides a relative, uncalibrated indication of input power level.

3-41. The major feature of the manual noise parameter measurement is improved accuracy. The

measurement method utilizes a substitution technique that eliminates potential errors due to the

direct reading accuracy of the SNM.

3-1 0

EXCESS

NOISE RATIO

dB

Y FACTOR

dB

20-

1 9 -

18-

17 —

1 6 -

15 -

14-

1 3 -

12 -

EFFECTIVE

INPUT NOISE

TEMPERATURE

KELVINS

10000:

8000

6000
5000

4000

3000 - i :

2000

1500

1000

800

700

600'
500

400
300

200

100 -I E

NOISE

FIGURE

b-16

15
14

13

E- 12

11
10

9

r 8

7
6
5

4

E- 3

2

1

0

dB

— 6

— 7

— 8

- 9

— 10

-11

— 12

-1 3

11 -

10'

-1 4

■15

Figure 3-7. Nomograph for Determining Noise Figure or Temperature

3-42. The measurement is more time-consuming and difficult than the automatic measurement
described earlier, and it requires additional equipment; however, it does provide a convenient
means of checking the performance of the SNM and calibrating the unit.

3-43. The set-ups are the same as those described earlier, except that a Precision IF Attenuator is
inserted just prior to the SNM IF input; however, it may be necessary to insert additional gain due
to the attenuator insertion loss. A typical attenuator suitable for this purpose is the AILTECH 32
Series (see Figure 1-7).

3-44. The measurement procedure is as follows:

a. Remove the top cover and locate MAN-AUTO switch S101, Noise generator ON-OFF

switch S102, and Manual GAIN control R140 on the IF-Video Board (see Figure 3-5).

3- 1 1

b. Set MAN-AUTO switch S101 to MAN, and Noise Generator switch S102 to OFF.

c. Set the Precision Attenuator to 0 dB, and adjust manual GAIN control R140 for a

convenient reference indication on the upper 50% of the meter scale (preferably
with the RANGE switch in LOW). If the signal level is too low to achieve this
condition, the ENR thumbwheel switch may be set to a lower number. If the signal
is still too low, switch to the HIGH range. Note the meter indication.

d. Set Noise Generator ON-OFF switch S102 to ON. Note that the meter indication goes

to the right.

e. Increase the setting of the Precision Attenuator until the meter indication returns to

the reference noted in (c).. Record the attenuation change which is the Y-factor in

dB.

f. Noise Figure or Operating Noise Temperature may be calculated from Equations 3-2.

P(dB) = ENR(dB) -10 Log (Y -l) (3-2a)

290 (ENR)

op

In both proceeding equations the ENR is the actual effective value after decoupling

or attenuation (if any) — not the setting of the thumbwheel switch. Note also that
ENR must be expressed as a power ratio for use in'(b). Y-factor is also expressed as
a power ratio in both equations. (

3-45. The noise parameters may also be calculated using the AILTECH Noise Figure Slide Rule,
Figure 3-6 or the nomograph of Figure 3-7.

Y-l

(3-2b)

3-12

CHAPTER IV

THEORY OF OPERATION

4-1. INTRODUCTION

4-2. This chapter contains noise figure measurement general theory and associated mathematics,
and an overall functional block diagram description of the SNM. Also included are detailed, in
dividual circuit descriptions.

4-3. GENERAL THEORY

4-4. Noise Figure Theory

4-5. Noise Figure can be defined as the ratio of the noise power available at the output of a net
work, when the input termination is at the standard reference Temperature (TQ = 290K), to that
which would be available at the output of an ideal noiseless network of otherwise identical char
acteristics. This can be expressed mathematically as:

N

__

F =

where:

F = Noise Figure Ratio

N = Noise Power (i = input, o = output)

G = Gain of network

By rearranging equation 4-1,

Nq = NjFG (4-2)

The noise power available at the input is that generated by the input termination and can
be written as:

Nj = kT0B (4-3)

where:

k = Boltzmann’s constant = 1.38 x 10 joules/K

2. (4-1)

GNj

OO

B = bandwidth in Hz

Tq = standard reference temperature (290K)

4- 1

NOTE

All temperatures in these equations are expressed as absolute temperatures
(Kelvins) and are related to the Centigrade (Celsius) scale as follows:

K = °C + 273

Substituting in Equation 4-2,

N0 = kT0 BFG

(4-4)

Expansion of this relation yields:

N,

o

[kT0B + (F -l)kT0B]G

(4-5)

Although Equation 4-5 expresses noise figure implicitly in terms of its effect on the network output,
it is sometimes considered more basic than Equation 4-1 because:

• It can be used to show the effect of an input termination temperature differing from the
reference temperature (TQ).

• It can be conveniently represented pictorially.

• It provides the basis for an indirect, but convenient method of measuring noise figure.

Figure 4-1 is a representation of Equation 4-5. Noise source A is the input termination while
noise source B is a fictitious source representing network contribution to the noise output with
reference to the input.

4-6. Noise Figure Measurement

4-7. Figure 4-1 can be modified as indicated in Figure 4-2. A switch has been added so that the
original input termination (A) can be disconnected and the network input terminated in a second
source (C) at temperature T2 (the temperature of the noise generator).

The available output power of the network for this condition is:

No = CkT2B + kToB G

Dividing Equation 4-6 by Equation 4-4 yields:

N o 2 T 2 + To (F-D

F

4-2

(4-6)

(4-7)

(4-8)

Figure 4-1. Equivalent Noise Representation of a Noisy Network

Equation 4-8 is the basic relation for determining noise figure. The numerator is called excess noise
ratio and is usually expressed simply as ENR. It represents the relative increase in noise power at
the network input when the switch is operated. If ENR is known, the ratio N ^ / N ^ (commonly

called Y-factor) can be measured, and the noise figure computed from Equation 4-8. Note that it

is not necessary to measure the absolute power levels at the network output, merely their ratio.

Therefore,

F =

or, expressed in dB,

F(dB) = ENR(dB) -10 Log (Y -l) (4-9b)

ENR

------ (4-9a)
Y-l

4- 3

4-8.

4-9. In those applications where it is not possible to separate a standard termination from a
termination with known ENR as in an operating radar system, a different measurement must be
taken. Here, a front-end performance factor (operating noise figure or noise temperature) is
measured. Since it is very difficult to separate system noise from the antenna or receiver input
generated noise, the two are lumped together and measured. Figure 4-3 illustrates this technique.

Operating Noise Figure ¿nd Temperature Measurement

Figure 4-3. Equivalent Representation of an Operating Noise Measurement

4-10. The element marked “ C” represents the directional coupler through which the noise is
injected. Te is the effective input noise temperature of the receiver and comparison with
Figures 4-1 and 4-2 shows that it is related to noise figure by:

TP = (F-l) T

T^ (Figure 4-3) represents the effective antenna temperature. The available output noise power
from the network under operating conditions is given by:

k(cTn + Ta + Te)BG (4-11)

When the reference noise source is energized (switch connected to D) the available output
noise:

k(cT2 + Ta + Te)BG

Dividing Equation 4-12 by Equation 4-11 yields:

N

o2

N

ol

Adding -1 to both sides of the equation and rearranging terms,

cT2 + Ta + Te

cTo + Ta + Te

(4-10)

(4-12)

(4-13)

. Y -l = c(T2 - T 0)/cT0 + Ta + Te

(4-14)

4- 4

0

In Equation 4-14, the term cTo in the denominator represents the portion of noise coupled into the
system from the noise source when it is deenergized. In most systems, the noise source is decoupled
by at least 20 dB and therefore, the term represents an insignificant noise contribution and can be

disregarded. Realizing that (T2 -T0)/TQ is the ENR of the reference noise source (Ta + Tg) is
the operating noise temperature (TQp), and the operating noise figure (FQ) is (Ta + Te)/TQ, terms
in Equation 4-14 can be rearranged to obtain:

Fop = cENR/Y-1 (4-15a)

or

Fop (dB) = ENR(dB) - c(dB) -10 Log (Y -l) (4-15b)

This relation has the same basic form as Equation 4-9. The quantity cENR represents the power
available from the system noise source at the receiver input.

Alternately,

Top = cTq (ENR) (4-16)

Y-l

4-11. FUNCTIONAL DESCRIPTION (AUTOMATIC NOISE MEASUREMENT)

4-12. The functional circuitry required to make a noise measurement is contained on the IF-
Video Board while the Power Supply Board contains the regulated power supplies and the noise
source modulator. See Figure 4-4 for an overall block diagram of the AIL TECH System Noise
Monitor.

4-13. A free-running multivibrator, operating at approximately 285 Hz modulates the DC power

source for the Noise Generator, alternately energizing and deenergizing the unit. The resultin g
two noise levels are applied to the system under test. The IF output of the system will also be
two levels of noise where the lower level represents the system noise when its input is normally
terminated. The higher level is the system noise plus the generator noise. These signals are further

amplified by the IF amplifier in the SNM and are then detected by a square law device providing
two voltages proportional to the noise powers in the IF signal. A sample of this detected signal is

supplied to an AGC amplifier that is gated to provide an output only during the time the noise

generator is turned off. This output is used to control the gain of the IF amplifier, so that the
noise-off signal is maintained at a constant level.

INPUT
FROM
DUT

The above procedure may be described mathematically as follows:

The Noise-on voltage at the output of the square law detector is given by:

v 2 = PN2 (4-17)

The Noise-off voltage by:

v x = pNi (4-18)

TP101

FRONT

F

L

T

Z101, Z102

IF

AMPLIFIER

Z103

SQUARE LAW DETECTOP

TP 104
TP111

Z111B

o

AGC

AMPLIFIER

Z104B, Z108-111, Z112C, D

Z104

VIDEO

AMPLIFIER

Z115C Z116A,B,C

(?)

TP112

TO NOISE SOURCE

Z115A, B Z114E, F

Z203

NOISE SOURCE

MODULATOR

f

(" fro n t p a n e l

Figure 4-4. Functional Block Diagram

4-5/4-6

s

Where

p = constant

N i = Noise power available at the output of the UUT.

The difference between these voltages is indicated by the panel meter.

V = V 0 -Vi

v m v 2 v 1

or

Vm = P(N2 -N x)

Rearranging terms

N

Vm - pNi

2

N

1

From the previous discussions:

N2

— = Y
N i

Therefore,

Vm = PN1 (Y-1)

From Equation 4-9a

/ENR \

v m = PN ! —

-1

(4-19)

(4-20)

(4-21)

(4-22)

(4-23)

(4-24)

Equation 4-24 indicates that, if ENR is known and Nj_ is constant (a condition satisfied by the
gated AGC amplifier), the meter voltage is inversely proportional to the noise figure of the unit
under test. This is a highly desirable result since lower noise figures read closer to full scale and thus
greater resolution is achieved.

Also, from Equation 4-16:

Y-l = —

cT_ (ENR)

T,

------

op

!

(4-25)

and

c(ENR)

Vm = PN 1

op

(4-26)

4-14. Additional insight into the operation of the measuring circuits can be gained by reference
to Table 4-1 which illustrates the effects of the various timing and gating signals. The waveforms
in Table 4-1 are shown only to illustrate operation and should not be used for troubleshooting.
Exact waveforms are provided in the Maintenance Chapter of this manual.

4-7

REF .

NOISE +28V —1 NOISE

1 SOURCE OFF

GATE 0V-

NOISE

ON

V j

-----

j NOISE p— I

1. The basic timing oscillator generates a gate
which drives the noise source on and off.

2 FROM

INPUT

DUT

REFERENCE
GATE
TP106
TP112 _

DETECTED
OUTPUT
TP 101

AGC GATE
TP 107

0V

AGC CLAMP I" 1 I OPEN

TP108 CKT

ip OPEN I— 1

0V-

DUT + NOISE SOURCE

DUT NOISE

ILJl

_ _

NOISE

ON

NOISE OFF

"O " REFERENCE

BLOCK PASS

L fl

*

i r “ L r

SHORT

CKT

I CKT I L _

2. The input from the DUT is an IF signal con
sisting of periods of system noise plus added
noise from the noise source alternating with
periods of system noise alone.

3. The reference gate turns off the IF amplifier
for a short period of time at the start of each
noise on and noise off period. This establishes
a “0 noise” reference eliminates any noise gen
erator transients.

4. The detected output consists of a three-level
signal made up of a zero noise reference period
proceeding each noise on and noise off period.
A synchronous integrator converts this signal
to D.C. proportional to the difference between
the noise on and noise off levels. The video sig
nal is also applied\to the AGC circuit.

5. The AGC Gate signal applied to the series ana
log gates, passes only the zero reference and
noise off signal.

6. The AGC Clamp establishes ground potential
during the zero reference period. When the
clamp releases at the start of the Noise Off
time, the change in level equals the difference
between zero reference and noise off.

7. Due to the action of the AGC Gate and the
AGC Clamp only the Noise Off video is applied

AGC
VIDEO

Table 4-1. Functional Illustration — Timing and Gating

4-15. CIRCUIT DESCRIPTIONS

4-16. The following paragraphs describe the operation of the circuits within the System Noise
Monitor. The order in which each description is presented generally follows the primary signal

path rather than by complete sub-assembly description. Reference is made to the schematic

diagrams, Figures 5-16, 5-17. .

to the AGC amplifiers. This amplified signal is
integrated, converted to D.C. and applied to
the IF amplifier as a gain control voltage. The
net result is that the noise off signal remains
constant.

4-8

4-17. IF Amplifier. Signals applied to the IF input are transformer coupled via T101 to the

first IF amplifier, Z101. C154 is adjusted for best input match, and the center frequency of
the input stage is set by C102. T101 also provides a 2:1 voltage step-up.

4-18. The gain of the entire IF amplifier is controlled by application of the AGC signal to Z101.
In the manual mode of operation, the AGC signal is replaced by a DC voltage set by R140. The AGC
input will typically be between +5 volts at threshold and +7 volts at the high input level limit.

4-19. Additional IF gain is provided by Z102. The gain control input is driven by the IF gate
(Ref. 3, Table 4-1) to establish the zero noise reference. The IF gain of Z102 goes to zero when J
the gate signal goes positive. When MAN-AUTO switch S101 is set to the Manual mode, the
narrow pulse pair is replaced by the output of the timing generator.

4-20. The output of Z102 is transformer coupled in a balanced configuration to the square-law
detector. Cl 14 tunes the output circuit to the SNM center frequency.

4-21. In a typical unit operating at the sensitivity limit, the overall IF gain will be about 35 dB.

This will vary somewhat from unit to unit and at the various intermediate frequencies.

4-22. Square Law Detector. The detector, Z103, is a monolithic balanced modulator whose

output contains a term proportional to the product of its two inputs. If the inputs are in

parallel, then the output voltage is proportional to the square of the input voltage or the input

power.

4-23. Since the input signal has three amplitudes — noise on, noise off, and zero reference — the
detected output will be a three level signal with some low frequency noise on the noise on and
noise off levels (see Table 4-1, Ref. 4).

4-24. Variable Gain Amplifier. From equations 4-24 and 4-26 it can be seen that the cali

bration of the SNM for various noise generators with different ENR’s can be maintained by
changing the gain (proportionality constant) by the differences in dB. In the SNM, the calibra
tion for a specific ENR is established by the gain of the two-stage video amplifier cascade, made

up of Z105A and B. Each stage consists of an operational amplifier, operating in the inverting

feedback mode; thus, the gains are determined by the feedback resistor values. These resistor

networks are contained in 14 lead DIP’s and are selected by the front panel thumbwheel switch.

4-25. Synchronous Integrator and Meter Amplifier The three-level video signal is applied

to the series-shunt switch combination made up of Z106C and D. Z106C is driven by the
inverse of the AGC Clamp signal (Table 4-1, Ref. 6) clamping the output side of C140 to ground

during the Noise-Off period. Z106D is a series switch driven by the inverse of the AGC Gate

(Table 4-1, Ref. 5), and passes signals only during the Noise-on period. The clamping action of
Z106C causes the amplitude of the video pulse at R122 to be equal to the difference between the

Noise-On and Noise-Off signals. R122 and C131, in combination with Z107B form a non
inverting integrator with the meter in the feedback loop. R124 and R161 are calibration adjust

ments for the Low and High ranges respectively. R125 sets the voltage of the Recorder Output.
Z117B is used in a similar manner to drive an external meter. A 100 microamp, IK meter inserted
between R166 and R165 will track the excursions of the front panel indicator.

4-26. AGC Amplifier. The video output of Z104, the Video Driver (TP101) is also applied

to the AGC Amplifier. This circuit is comprised of a series of gates, clamps, and amplifiers
designed to provide a DC output proportional to the Noise-Off detector level. The high-gain

requirements of the circuitry are fulfilled by AC amplification to reduce DC drift problems.

4-9

4-27. Z108A is a series switch that permits only the Zero Noise Reference and Noise Off
detector level to be applied to the first amplifier Z104B. Z108B clamps the input of Z104B to
ground except during the Noise O ff period. Z108C, Z108D, R131 and C134 make up a syn
chronous integrator similar to that described in 4-25 except that the DC level developed is pro
portional only to the Noise Off detector level.

4-28. The DC signal is chopped (converted to AC) by Z110A and B, amplified by Z109A, and
compared to a similarly chopped reference signal in differential amplifier Z111A. The reference
signal is developed by zener diode CR101 and the voltage divider made up of R129 and R130.

Z110C and Z110D convert the reference to AC in synchronism with the AGC signal. Z109B
provides equivalent amplification.

4-29. The output of Z111A is synchronously integrated by Z112C, Z112D, R137 and C137.
CR102 protects the analog gates from excessive reverse voltage when the input IF is below the AGC

threshold. Z111B provides additional DC amplification. The output at TP104 will vary from about

5 volts at threshold to about 7 volts at the upper signal level limit. The timing of the various gates
and clamps is shown on the simplified schematic. The video signal is out of proportion and is

shown for reference only.

4-30. Z113A provides the Signal Monitor output. Z113B drives the front panel Signal Level lamp

via Q101.

4-31. Timing Signal Generator (Figure 4-5). This circuit, consisting of three integrated circuit
packages, provides the timing signals for the various analog gates and switches and the modulation
gate for the noise source. Waveforms are shown on the simplified schematic, Figure 4-5, for ref

erence.

4-32. Z114A, Z114B, R146 and C138 make up a free-running oscillator which provides an

asymetrical rectangular signal at about 285 Hz. This signal is inverted by Z114C and is used to

drive the series switches of the AGC and AGC reference DC to AC converters and the final AGC

synchronous integrator (Z110B, Z110C and Z112D).

4-33. The output of Z114C is again inverted by Z114D. The signal is the gating input for the

noise source modulator and is also used to drive the shunt clamps in the AGC and AGC reference

DC to AC converters and the final AGC synchronous integrator (Z110A, Z110D and Z112C).

4-34. Z115A and Z115B make up a one-shot multivibrator driven alternately by the differentiated

outputs of Z114C and Z114D. Z115A is a three-input NOR gate; therefore, its output is low at all
times except when all three inputs are simultaneously low. This is illustrated by Table 4-2.

4-35. In the quiescent condition, the output of inverter Z115B is LOW because its input is re
turned through R149 to +12 volts. Thus, all three inputs of NOR-gate Z115A are LOW (R147 and
R148 returned to ground), and its output is HIGH. When the positive going edge of the signal at

Z114C output occurs, the input of Z115A is momentarily driven HIGH, causing its output to go
LOW. This drop in voltage appears at the input to Z115B and the inverter output goes HIGH.
Feedback to Z115A input causes the action to be regenerative, resulting in the output of Z115B
being driven rapidly to +12 volts where it remains until C141 is charged to a sufficiently positive

voltage for Z115B to start conducting. The regenerative action then reverses, and the output of

Z115B is rapidly driven to zero. The time constant is such that the resulting pulse is about 100 mi
croseconds wide. The entire sequence repeats on the positive going edge of the output from Z114D.

4-36. The overall result, after two inversions through Z114E and Z114F, is a positive pulse at the

start of each Noise On and Noise Off period. This signal is used to gate the second IF amplifier

(Z102) off, establishing the zero noise reference. .

4-10

0

Z114D-10

Z115A-4

Z114F-15
TP 106

Z116A-6

©

(INVERT FOR TP107)

Z115C-10

©

(INVERT FOR TP108)

Figure 4-5. Timing Signal Generator

Simplified Schematic and Timing Diagram

4- 1 1/ 4 - 1 2

TABLE 4-2. 3-INPUT NOR CIRCUIT TRUTH TABLE

INPUTS OUTPUT

A

0 0

0

0

0

1

1 0

1

1

*1 = HIGH OR TRUE

0 = LOW OR FALSE

FOR CMOS LOGIC: 0 = 0 to +3.5 volts

B

0

1

1

0

1

1

c

0 1*

1

0

1

0 0

1 0

0

1

1 = 8 to +12 volts
(+ 12 volts VDD)

0

0

0

0

0

4-37. The output of Z114D and the IF gate are also applied to NOR gate Z116A. This results in
a positive pulse equal to the Noise-On period, less the zero noise reference time. This is used to
control the series synchronous integrator switch (Z106D) in the meter circuit (see paragraph 4-25),
and is applied to NOR gate Z116C connected as a simple inverter. The resulting signal at TP107
is the series AGC gate.

4-38. NOR gate'Z115C is driven by the output of Z114C (TP105) and the IF gate. Its output is
a positive signal equal to the Noise-Off period less the zero noise reference time. It is used to drive
the shunt clamp in the meter circuit synchronous integrator (Z106C),and inverter Z116B. The out
put of the inverter (TP108) drives the shunt clamp in the AGC input stage (Z108B) and first syn
chronous integrator (Z108C).

4-39. Power Supply Board

4-40. The AILTECH 7310/7320 SNM require three different voltages: +12 VDC at 200 mA,

-12 VDC at 150 mA, and +28 VDC at less than 20 mA. All voltages are derived from individual
monolithic regulators and are protected by current-limiting circuits. Because of the simplicity
and standard nature of the circuitry, partial schematics are not shown here. See Figure
for a complete schematic diagram of the power supply.

\

4-41. +12 Volt Regulator. The +12 volt output from Z201 is set by resistors R204, R205, and
R206. Resistor R205 adjusts the +12 volt supply used to set certain threshold levels on the IF
Video Board. The short circuit current of the +12 volt supply is determined by resistor R201.
Capacitor C203 is a compensation capacitor while capacitor C204 acts as a noise filter.

4-42. -12 Volt Regulator. The -12 volt supply is regulated by Z202. Resistor R207 and R208
determine the exact value of the regulated output, which may vary from -11.8 VDC to -12.2 VDC.
The short circuit current for the -12 volt supply is determined by resistor R209. Capacitor C208 is

the compensation capacitor, while capacitor C207 filters noise.

4-43. +28 Volt Noise Source Supply. The +28 VDC supply is regulated by Z203. A remote shut

down feature is designed into this supply to permit modulation by the 285 Hz clock on the IF
Video Board. Transistor Q202 provides this capability. The 28-volt output can be precisely set
by variable resistor R215. Resistor R212 provides short circuit protection. This supply is used

exclusively to power the noise source.

4-14

CHAPTER V

MAINTENANCE AND ADJUSTMENTS

5-1. GENERAL
5-2. This Chapter contains Performance Verification, Adjustments, and Troubleshooting.

Schematics, printed circuit board component locations, and wiring diagrams will be found in the

Troubleshooting section. Spares and replaceable parts are in Chapter VI.

5-3. PERFORMANCE VERIFICATION

5-4. The following procedures (recommended at 90 day intervals) are designed to insure the user
that his AILTECH 7310 or 7320 is operating within specifications. Only those specifications critical
to performance are checked. In some cases, more than one specification is verified by the same pro
cedure. Where a specification is a function of adjustment, reference is made to the paragraph
describing that adjustment.

5-5. Table 5-1 lists the test equipment required for performance verification.

TABLE 5-1. TEST EQUIPMENT REQUIRED FOR PERFORMANCE VERIFICATION

Recommended Manufacturer

Description

Signal Generator, 10 to 100 MHz, calibrated
output -90 to -30 dBm

Digital Voltmeter, DC, 0 to 28 volts,

AlA digits.

Noise Source, frequency compatible with
the input of the simulated UUT

Precision Variable Attenuator, continuously

variable

5-6. Minimum Operating Level. This procedure checks the basic sensitivity of the SNM at its
center frequency. Its primary purpose is to insure that the instrument is properly tuned. If the
unit fails this check, refer to paragraph 5-40.

a. Connect a signal generator to the IF Input of the SNM. Set the generator frequency

to the center frequency of the SNM. Set the generator output level to less than

-80 dBm.

Boonton 512

Systron-Donner 7004A

AILTECH 7600 Series

AILTECH 3200 Series

and Model

b. Increase the output level until the green Signal Level light on the front panel is

illuminated. Increase the generator level an additional 5 dB.

c. Note that the generator level is less than -70 dBm.

5 -1

5-7. Noise Generator Power. The purpose of this check is to insure that the voltage applied to
the solid state noise generators is within specified limits. This voltage determines the excess noise
ratio of the noise generator and the subsequent overall accuracy of the noise figure or temperature
measurement. If the unit fails this check, refer to paragraph 5-40.

a. Connect a DVM to The Noise Source Output Connector.

b. Set AUTO-MAN switch S101 to MAN. Set Noise Generator ON-OFF switch S102 to

OFF. Note that the DVM indicates less than 0.3 volts.

c. Set Noise Generator ON-OFF switch S102 to ON. Note that the DVM indicates 28.00

+0.05 volts.

d. Disconnect the DVM. Connect an oscilloscope to the Noise Source output. Set

AUTO-MAN switch S101 to AUTO, Noise Generator ON-OFF switch S102 to OFF.

Note that the waveform is an asymmetrical rectangular waveshape with a positive level

of +28 volts and a low level of zero.

5-8. Accuracy. This specification is defined as the maximum permissible deviation of the SNM
indication (operating in the normal, automatic mode) from a manual Y-factor measurement on the
same unit-under-test (UUT). The accuracy is checked by making a manual Y-factor measurement,
calculating noise figure or temperature, and comparing the result to the automatic indication. In
general, it is good practice to make several manual measurements and average the results. The man
ual measurement procedure was detailed in paragraph 3-44 and is repeated here for convenience.

a. Set up the equipment as shown in Figure 5-1. See paragraph 5-9 for UUT require

ments.

b. Remove the top cover and locate MAN-AUTO switch S101, Noise Generator switch

S102, and Manual Gain Control R140 on the IF-Video Board. (See Figure 3-5.)

c. Set MAN-AUTO switch S101 to MAN and Noise Generator switch S102 to OFF.

d. Set The Precision Attenuator to 0 dB, and adjust Manual GAIN control R140 for a

convenient reference indication on the upper 50% of the meter scale (preferably with
the RANGE switch in LOW). If the signal level is too low to achieve this condition,
the ENR thumbwheel switch may be set to a lower number. If the signal is still too
low, switch to the HIGH range. Note the meter indication.

e. Set Noise Generator switch S102 to ON. Note that the meter indication goes to the

right.

f. Increase the setting of the Precision Attenuator until the meter indication returns to

the reference noted in (d). Record the attenuation change. This is the Y-factor in
dB.

g. Set Noise Generator ON-OFF switch S102 to OFF. Return the Precision Attenuator

to its original setting. If the meter is not within +0.05 dB of the original reference,
repeat the measurement.

5-2

h. Calculate Noise Figure or Operating Noise Temperature, as required, from Equations

3-2, the AILTECH Noise Figure Slide Rule, or Figure 3-7.

Figure 5-1. Set-up for Checking SNM Accuracy

i. If the noise figure is greater than 3 dB or the noise temperature is greater than 120 K,

recalculate the quantity based on an artifical ENR low enough to obtain these condi
tions. Record the value of ENR used.

j. Bypass the Precision Attenuator. Set MAN-AUTO switch S I01 to AUTO, Noise Gen

erator ON-OFF switch S102 to OFF, and the front panel RANGE switch to LOW.

k. Set the ENR thumbwheel switch to the value recorded in Step (i). Note that the meter

indication is within +0.25 dB of the value calculated in Step (i). See paragraph 5-18
for adjustment.

1. Add sufficient attenuation between the noise source and the UUT and/or increase the
ENR thumbwheel setting to obtain an indication between 6 and 9 dB (noise figure) or
240 and 580 K (operating noise temperature). Record the ENR setting.

m. Re-insert the Precision Attenuator, and repeat Steps (b) thru (g).

n. Calculate Noise Figure or Operating Noise Temperature, as required, from Equations

3-2, the AILTECH Noise Figure Slide Rule, or Figure 3-7. Use the ENR setting of
Step (1) for the calculation.

o. Bypass the Precision Attenuator. Set MAN-AUTO switch S101 to AUTO, Noise Gen

erator ON-OFF switch S102 to OFF, and the front panel RANGE switch to HIGH.

p. Set the ENR thumbwheel switch to the value used to calculate the required noise

parameter in step (n). Note that the meter indication is within ±0.25 dB of the value
calculated in Step (n). See paragraph 5-18 for adjustment.

5-9. The simulated UUT used for this check must meet the same gain and noise figure conditions
noted in paragraph 3-24; i.e. the “ noise-on” signal must not be greater than 40 dB above the actual
sensitivity as determined in paragraph 3-23, and the “ noise-off” signal must not be less than the
sensitivity. In addition, input and output frequencies must be compatible with the noise source and
the SNM respectively.

5-10. CHECKS AND ADJUSTMENTS .

5-11. Procedures for checking and adjusting the SNM are provided in paragraphs 5-13 thru 5-23.
All adjustments in the AILTECH 7310 and 7320 SNM’s are available with just the top cover
removed. The adjustment locations are shown in Figure 5-2.

5-3

Lfer

D

. R205

+12 VOLTS

R215 —

+28 VOLTS

C102

fc> Zi"

C154 '

Zin

R125

RECORDER

OUTPUT

'V

oy^DQ

g

]ÜQ

~ z m

"UTJ

n

ö — jv n=

oa KÍM

o

f l

D —---------------------— s

G

00 yj

C114

fc

- — R169

SIGNAL MONITOR

R161

HIGH RANGE CAL

R124

LOW RANGE CAL

R150

oo SET

Figure 5-2. Adjustment Locations

5-12. Components on the IF-Video P.C. Board have symbol numbers in the 100 to 199 range.

Symbol numbers of power supply components are in the 200 to 299 range. Test points on the
printed circuit boards are marked only with the last digit; thus, TP 202 on the power supply board
is marked simply “2 ” .

5-13. POWER SUPPLY ADJUSTMENTS

a. All voltages are referenced to chassis ground.

b. Use a DVM and an oscilloscope with shielded leads to measure and adjust the power

supplies in accordance with Table 5-2.

TABLE 5-2. POWER SUPPLY CHECKS AND ADJUSTMENTS

Test Point Adjust

2 0 1 +20 ±3

2 0 2 R205

203

204 - 1 2 ± 1
205 *

206

206

NOTES: 1. MAN-AUTO switch S101 set to MAN, Noise Generator ON-OFF switch

S102 set to ON.

2. MAN-AUTO switch S101 set to MAN, Noise Generator ON-OFF switch
S102 set to OFF.

5-14. IF ADJUSTMENTS

Voltage

Vdc

+12 ±0.05

-20 ±3

+40 ± 6

R215 +28 ±0.05

0 ±0 .2

Max. Ripple

mV, p-p

800

5

400

5

2 0 0

40

N/A 2

Notes

1

5-15. There are three interacting adjustments in the IF circuit C154, C102, and C114. C154 and
C102 affect the input impedance and center frequency; C114 affects center frequency. If these
adjustments are improperly set, the unit could appear low in sensitivity (minimum operating level
too high).

5-16. Preliminary

a. Set MAN-AUTO switch S101 to MAN.

b. Set Noise Generator ON-OFF switch S102 to OFF.

c. Set front panel RANGE switch to LOW.

5-5

d. Connect a signal generator set to the center frequency to the IF Input. Adjust the

output level for a mid-scale reading.

5-17. Procedure

a. Adjust C102, C114 and C154 for maximum, up-scale indication (minimum noise fig

ure) on the meter (C154 will have the least effect).

b. Connect the vector voltmeter to the IF input and adjust C102 and C154 for a re

flection coefficient of less than 0 .1 .

c. Connect the signal generator to the input and readjust C114 for a peak indication.

d. Check Minimum Operating Level as described in paragraph 5-6.

5-18. METER ADJUSTMENTS

5-19. These adjustments insure the basic accuracy of the instrument. They should be varied only

if the Performance Verification Check of paragraph 5-8 so indicates. ''

a. Set MAN-AUTO switch S101 to AUTO, Noise Generator ON-OFF switch S102 to OFF.

With no signal connected to the IF Input, adjust R150 until the meter indicates

' infinity.

b. Perform the low range calibration check described in paragraph 5-8. If necessary, ad

just R124 u n til the AUTO indication agrees w ith the manual measurement
result.

c. Perform the high range calibration check described in paragraph 5-8. If necessary, ad

just R161 u ntil the AUTO indication agrees with thé manual measurement ;
result.

5-20. AUXILIARY OUTPUT ADJUSTMENTS

5-21. These adjustments are not critical to instrument performance, and need be set only if the

user requires these auxiliary outputs.

5-22. Signal Monitor

a. With MAN-AUTO switch S101 in AUTO, apply an input signal at the center frequency

to the IF Input. Increase the level until the front panel SIGNAL LEVEL light just
comes on. “

b. Connect a DVM between pin 4 of J1 (rear panel) and ground (pin 5 of Jl).

c. Adjust R169 until the meter indicates 0.0 ±0.5 volts.

5-6

d. Increase the signal generator output level by 50 dB. Note that the DVM indication

increases to about +5 volts.

5-23. Recorder Output

a. Set MAN-AUTO switch S101 to MAN., and Noise Generator ON-OFF switch S102 to

OFF. Connect a signal generator set to the center frequency to the IF Input, and a
DVM between pins 8 and 5 of J1 (or, TP103 and Ground).

b. Set the RANGE switch to LOW.

c. Increase the signal generator output until the meter indicates full scale (0 dB or 60 K).

d. Adjust R125 until the DVM indicates +1.0 ±0.5 volts.

5-24. TROUBLESHOOTING

5-25. Performance verification and the checks and adjustments of the proceeding paragraphs are
valuable aids to locating malfunctions within the SNM. In addition, the troubleshooting flow
charts, Figure 5-10 thru 5-15, are designed to isolate problems to a particular circuit area.

5-26. GENERAL INFORMATION

5-27. Tools

a. A special tool is required for servicing the connectors in the SNM. This is available

from AMP Inc. by ordering Connector Tool, P/N 91084-1. Instructions for use are
provided with the tool.

b. Integrated circuits should be removed from their sockets using an extraction tool to

minimize pin damage. A typical tool is the Augat Model T114-1.

c. Measurements taken directly from IC pins are facilitated by a spring clip designed for

that purpose. Typical types are the Pomona DIP-CLIP Models 3914 and 3916.

5-28. Transistors. Plastic encapsulated transistors are used exclusively throughout the SNM. Fig

ure 5-3 illustrates the physical configuration used. .

Figure 5-3. Plastic-Càse Transistors

5-7

5-29. Integrated Circuits. Both linear and digital IC’s are used in the 7310 and 7320 SNM’s. Fig

ure 5-4 illustrates the physical configurations used, and Figure 5-5 provides functional descriptions.

5-30. Logic Family. All digital integrated circuits in the SNM are cos/mos devices. This family
provides high noise immunity and good temperature stability. Positive logic is used throughout, so
a “True” condition is high, and a “ False” condition is low. High and low voltage values are the sup

ply voltage (+12 volts) and 0 volts respectively. In practice:

True (High or logical “ 1” ) = + 8 to +12 volts

False (Low or logical “ 0” ) = 0 to +3.5 volts

These values are nominal for a positive supply voltage (V ^ ) of +12.0 volts.

5-31. Logic Circuits. Only one type of true digital logic circuit (IC) is used in the 7310 and 7320.
This is the NOR gate or inverted OR. The NOR gate is characterized by the fact that its output is
always LOW except when all its inputs are simultaneously LOW. For the 3- input gates used in the
7310 and 7320, this is illustrated by Figure 5-6.

5-32. Analog Gates. Several gates, which pass or block analog signals depending upon the condi
tion of a control signal, are used in the 7300 System Noise Monitors. These gates are generally used

in series-shunt pairs to form DC to AC converters (choppers) or the inverse function, AC to DC
converters (synchronous integrators). Although the gates are complex cos/mos IC bilateral switches,

they are, for simplicty, shown as N-channel FET’s on the schematic (e.g.,: Z108). The operation

of the gates is illustrated by Figure 5-7.

5-33. Operational Amplifiers. Operational amplifiers are used to implement many functions, such
as summers, buffers, differential and offset amplifier. Figure 5-8 illustrates some typical circuits.

5-34. Printed Circuit Boards. The printed circuit boards (PCB’s) used in the AILTECH 7300
SNM’s are double-sided with platedrthrough holes; that is, there are conductor patterns on both
sides of the boards, and connections from top to bottom are via metallic plating of through holes.

5-35. The PCB’s are susceptible to damage from excess soldering heat. Use a soldering iron of
less than 60 watts rating when working on the 7300 PCB’s, and use a suction device to remove
excess solder from component mounting holes. If possible, when replacing a component, clip the

leads of the device to be replaced close to its body; thus, the old leads can be used as wrap-around
terminals for soldering the new component in place. When soldering on the PCB’s use a solder with
a non-corrosive flux core, and clean the excess flux off the board after all soldering is complete.

5-36. Damaged sections of the printed wiring can be repaired by soldering a length of bare, tinned

copper wire across the damaged area.

5-37. Printed Circuit Board Connectors. Connections to the printed circuit boards are made via

AMP type 87133-X. Connector tool, AMP P/N 91084-1 is required to service these connectors.
Pin number layouts, as they appear on the boards are shown on the overall wiring diagram. In gen

eral, the pins are numbered consecutively with the numbers increasing in the same direction in each

row (as contrasted to the continuous system used with IC’s). This is illustrated by Figure 5-9 which

is the layout of a 1 0 pin connector.

5-8

CASE A

CASE B

Figure 54. Integrated Circuit Case Styles

D

CASE D

5-9/5-10

NIC1463 BLOCK DIAGRAM

INV INPUT A
NQN-INV INPUT A
OFFSET NULLA
V
OFFSET NULL B
NON-INV INPUT B
INV INPUT B
OFFSET NULL B
V + B
OUTPUT B
NO CONNECTION
OUTPUT A
V + A
OFFSET NULL A

+V.

UNREGULATED

i

START-UP

AND

SHUT-DOWN

CONTROL

MC1469 BLOCK DIAGRAM

NOISE

7 P FILTER

DC SHIFT

Vref AND

Iref

BIAS DC LEVEL SHIFT

MC1469R POSITIVE VOLTAGE REGULATOR - CASE C

12

DC SHIFT 8

SENSE

OUTPUT

OUTPUT
REFERENCE

6 ~

__

OUTPUT
SENSE ERROR AMP AND

COMPENSATION
AND CURRENT LIMIT

REGULATED

OUTPUT

UNITY GAIN

REGULATOR

AIN 1

Aai it 2

'O U T “ E

B„, 3

JOUT ° d

B,m 4

/JA747CA DUAL OP AMP

CASE B

CD4016AE QUAD BILATERAL .

SWITCH

CASE B

CD4000AE HEX INVERTER

CASE D

CD4000AE DUAL 3-INPUT

NOR GATE PLUS INVERTER

CASE B

ßA723CA VOLTAGE REGULATOR - CASE B

3CONT 5 C l

:CONT 6 d

LIMITER

Figure 5-5. Integrated Circuits Functional

Illustrations

5-11

f

TRUTH TABLE

3 - INPUT NOR GATE

A BCX

0

0 0

1

0

0 1 0

0

1 0

0

0

1 1

0

1 0 0
1 0 1
1 1

1 1 1

0
0

0 0

0

+ V D D

««wan t»!'

IV W n V M H Vn H

-------

i i
i I

f l

Figure 5-6. 3-Input NOR Gate Operation

INPUT

CONTROL

OUTPUT

CD4016AE

SWITCH

5-12

Figure 5-7. Operation of the COS/MOS Bilateral Switch

*

R2

NONINVERTING AMPLIFIER

Figure 5-8. Typical Applications of Operational Amplifiers

1 • • 6

2 • • 7
3 • • 8

4 • • 9
5 • • 10

Figure 5-9. Pin Numbering Layout of a Typical AMP 87133 Connector

(View Looking Down on the Mating Pins)

5-38. Front Panel Lamps. DL-1 and DL-2, the Power indicator and Signal Level lamps respectively

are incandescent lamps. In the event one fails, the replacement procedure is as follows:

a. Strip the heat-shrink tubing from the connections on the rear of the lamp.

b. Unsolder the connections.

5-13

c. Using a pair of long-nose pliers, squeeze the three projections on the retainer clip

together. Maintain pressure and slide the clip back off the lamp.

d. Remove the lamp from the front.

e. Reverse the removal procedure to mount the new lamp. Use insulated tubing over the

solder connections.

5-39. ENR Thumbwheel Switch. This switch is held in place by spring loaded clips at the top and
bottom and is removed from the front of the panel. To replace the switch simply remove the
entire ENR Gain board by disconnecting the board edge connectors on the switch, depress the clips,
and free the switch by rocking it back and forth in the vertical plane. The new switch may then be
simply snapped into place,

5-40. TROUBLESHOOTING PROCEDURES

5-41. This paragraph provides troubleshooting procedures in the form of flow charts. These
charts, Figures 5-10 through 5-15 provide step-by-step procedures for fault isolation down to active
components and critical passive components. In general, these charts are meant as guidelines to
logical signal tracing techniques.

5-42. Waveforms keyed to conditions set up by the Troubleshooting charts are also provided;
however, as a further aid, waveforms typical of a functioning unit in its normal operating mode are
provided on the schematic diagrams which follow the charts.

5-43. Recommended spares and replaceable parts lists are located in Chapter VI.

5-44. FACTORY SERVICE

5-45. In the event a difficult service problem occurs, contact your nearest AILTECH Regional

Office or Sales Representative by letter, TWX or phone. Please indicate the model number, serial
number and specific details of the difficulty involved with as much additional information as you
consider necessary to aid in pin-pointing the cure to the problem.

5-46. Should it be necessary to return the equipment to the factory for repair or recalibation,

please contact AILTECH or an authorized sales representative in your area before shipping a unit.
In your communication arranging for a return, please be sure to include model number, serial num
ber, date of purchase and specific details concerning the problem (in the event of failure) or service
desired (in the event of recalibration).

5-47. When an instrument is returned for service, we will proceed to work on the instrument until
the charges reach $100. If the total charges exceed $100., an estimate of such charges will be sub
mitted for approval.

5-48. When spare parts are ordered, please indicate a description of the part as well as its part
number and also include the model number and serial number of the instrument being repaired.

5-14

.

.........................

POWER OFF ADJUST METER
ZEFiO PAR 2-16-

r

NO

1

'

SET LINE VOLT SELECTOR,
S101 IN AUTO

I YES

FUSES CORRECT FOR LINE

VOLTAGE SELECTED
AND OPERATIONAL

YES

RED POWER ON
INDICATOR ILLUMINATED

YES

1

CHECK AND ADJUST POWER
SUPPLY PAR 5-13, TABLE 5-2

YES

NO

NO

REPLACE M101

DISCONNECT LINE CORD

REPLACE F1, F2 CONNECT
LINE CORD

YES

1

f

-12VDC AT TP204
POWER SUPPLY BOARD

YES

TROUBLESHOOT POWER
SUPPLY SEE FIG 5-15

I

NO

TROUBLESHOOT POWER
SUPPLY SEE FIG 5-15

-12 VDC BETWEEN PINS 2 AND

* 20 ON J5 IF-VIDEO BOARD

YES

t

REPAIR BROKEN WIRE(S) AND/

OR P5 CONNECTOR PAR 5-37

-12 VDC BETWEEN PINS 2 & 5
ON J3 POWER SUPPLY BOARD

r

| REPAIR BROKEN WIRE(S) AND/
S OR P3-P4 CONNECTOR PAR 5-37

NO

REPAIR PRINTED WIRING
BETWEEN TP204 AND J3 ON

POWER SUPPLY BOARD

Figure 5-10. General Troubleshooting/Repair

Flow Chart (Sheet 1 of 2)

DWER ON.S101 IN AUTO.
ANGE SWITCH IN HIGH.
O INPUT

3 5-10. General Troubleshooting/Repair

Flow Chart (Sheet 2 of 2)

SI01 IN AUTO. SIG GEN AT -70

dBm CONNECTED TO INPUT

ï

REPLACE Z104. RECHECK
WAVEFORM.

W12

SIGNAL LEVEL
LIGHT ILLUMINATED

1 VDC + 20%

AT ZT10 PIN 8

YES

NO

REMOVE Z110. 1 VDC ± 20%
AT Z110 PIN 8

REP LAC

:e Z110

NO

CHECK R129, R130 AND/OR
REPLACE C135

1

REMOVE S101, CONNECT A

• CLIP LEAD BETWEEN TP106
AND TP112. ADJUST INPUT
SIGNAL LEVEL TO -70 dBm.

YES

' -

CHECK WAVEFORM AT Z104
PIN 10.

YES

1

' ■ _

CHECK WAVE
PIN 12.

FORM AT 2111

YES

W12

W13

NO

NO

1

DISCONNECT INPUT. NOTE
THAT WAVEFORM SWINGS
THRU 180° PHASE AND BE
COMES DISTORTED. W14

IS TYPICAL

W14

| VES

CHECK WAVEFORM A T CR102
ANODE. NOTE NEGATIVE
PORTION IS CLAMPED AT
ABOUT -0.7V

I ”

CHECK WAVEFORM AT Z112
PIN 10.

YES

1

' -

DC VOLTS AT TP104 ABOUT

_1 V. INCREASES TO ABOUT
+10 V AS INPUT IS INCREASED
TO -70 dBm

W15

NO

NO

NO

NO

e_5~r2r~AGG~Troubleshooting Chart

W10 Z109 PIN 6

0.5 V/cm
1 ms/cm
DC COUPLED

W11 Z109 PIN 10

0.5 V/cm
1 ms/cm
DC COUPLED

W12 Z104 PIN 10

2 V/cm
1 ms/cm
DC COUPLED

S101 REMOVED

TP 106 CONNECTED TO TP112

W14 Z111 PIN 12

5 V/cm

1 ms/cm
DC COUPLED

S101 REMOVED

TP 106 CONNECTED TO TP112, NO INPUT

W13 Z111 PIN 12

5 V/cm

1 ms
DC COUPLED
S101 REMOVED
TP 106 CONNECTED TO TP112

W15 Z112 PIN 10

0.2 V/cm
1 ms/cm

DC COUPLED
S101 REMOVED
TP106 CONNECTED TO TP112, NO INPUT

S101 IN AUTO. SIG GEN
CONNECTED TO I.F. INPUT
SET TO -70 dBm.

3L E S H 0 0 T TIMIN G
^ATO R. SEE FIG 5-14

W1

TP107
5 V/cm

1 ms/cm
DC COUPLED
SI 01 AUTO

Jggjraj

IBl

w m « » - - - - - - - - - - - - - - - - - - - - - - - - - -

mms rnt

SSI

W2

TP108
5 V/cm

SI 01 A U TO

1 ms/cm
DC C OUPLED

i/AVEF O RM AT TP 1 12

YES

\T -65 dBm. R140 MAX

K WAVEFORM AT C124

CTION.

YES

r

1

WAVEFORM AT C125,

• W5

YES

1

CE Z104 CHECK

IATED COMPONENTS

W3

NO

NO

NO

blU üfcN AT -30 dBm CHtCK
WAVEFORM AT Z103 PIN 8

YES

1

1 1

CHECK WAVEFORM AT Z103
PIN 10

YES

1

REPLACE Z103CHECK
ASSOCIATED COMPONENTS

W6

W7

NO

NO

CHECK WAVEFORM AT Z102
PIN 4

ipu-

CHECK WAVEFORM AT Z102
PIN 6

REPLACE Z102CHECK

ASSOCIATED COMPONENTS

NO

W8

YES

NO

. W9

YES

1

r

I

I [

TP112

W3

5 V/cm

1 ms/cm
DC COUPLED

S101 MANUAL

REPLACE Z101 CHECK

ASSOCIATED COMPONENTS

W4 C124, R114 JUNCTION

10m V/cm
1 ms/cm
DC COUPLED

S101 'MANUAL

-65 dBM INPUT

W6 Z103 PIN 8

10m V/cm
1 ms/cm
AC COUPLED

S101 MANUAL

-30 dBM INPUT

W5 C125, R116 JUNCTION

10 mV/cm
1 ms/cm
DC COUPLED

S101 MANUAL

-65 dBM INPUT

W7 Z103 PIN 10

10 mV/cPn

1 ms/cm
AC COUPLED
S101 MANUAL

-30 dBM INPUT

W8 Z102PIN4

10 mV/cm

1 ms/cm
DC COUPLED

S101 MANUAL

-30 dBM INPUT

W9 Z102 PIN 6

10 mV/cm
1 ms/cm
DC COUPLED

S.101 MANUAL

-30 dBM INPUT

Figure 5-11. IF Troubleshooting Chart

5-17

iMaMlwmm

wsmt

TP 107

5 V/cm
1 ms/cm
DC COUPLED

S101 AUTO

W20 Z114 PIN 10 W21 Z115 PIN 9

5 V/cm 5 V/cm

1 ms/cm 1 ms/cm
DC COUPLED DC COUPLED

W2

TP 108
5 V/cm

1 ms/cm
DC COUPLED

S101 AUTO

u

" ■ "" T r

,JW*l

?3r£

W23 Z116 PIN 6

5 V/cm
1 ms/cm
DC COUPLED

i

I

W19

TP 105
5 V/cm

1 ms/cm
DC COUPLED

W22 Z115 PIN 10

5 V/cm
1 ms/cm
DC COUPLED

S101 IN AUTO

W1 TP 107

5 V/cm

1 ms/cm
DC COUPLED

S101 AUTO

re 5-14. Timing Generator

Troubleshooting Chart

W20 Z114 PIN 10

5 V/cm

1 ms/cm
DC COUPLED

W2

TP 108
5 V/cm

1 ms/cm

DC COUPLED

S101 AUTO

W19

TP105
5 V/cm

1 ms/cm
DC COUPLED

W21 Z115 PIN 9

5 V/cm

1 ms/cm
DC COUPLED

W23 Z116 PIN 6

5 V/cm
1 ms/cm
DC COUPLED

W22 Z115 PIN 10

5 V/cm
1 ms/cm
DC COUPLED

S101 MANUAL
SIGNAL GENERATOR
SET TO IF ABOUT

-70 dBm INPUT.
RANGE SWITCH HIGH

R140 FULLY CW. METER
READS UPSCALE WITH INPUT
LESS THAN -65 dBm WITH ENR

SET TO 15.9 dB

YES

NO

SET RANGE TO LOW! ADJUST

INPUT LEVEL FOR CONVENIENT
WAVEFORM AMPLITUDE AT
TP101.W16 IS TYPICAL

W16

CHECK WAVEFORM AT Z105
PIN 12. W17 IS TYPICAL.
NOTE GAIN INCREASES FROM
UNITY AT 15.9 dB ENR AS ENR
INCREASES IN 1 dB STEPS.

YES

W17

X

CHECK WAVEFORM ATTP102.
W16 IS TYPICAL. NOTE GAIN

INCREASES FROM UNITY AS
ENR IS DECREASED IN 0.1 dB

STEPS. .

YES

?

NOTE WAVEFORM AT Z106
PIN 8 SAME AS ABOVE EXCEPT
BASELINE IS CLAMPED TO

0. .

YES

W16|

W18

NO

NO

NO

ADJUST INPUT FOR 2 dB

INDICATION. REDUCE
ENR SETTING IN 0.1 dB
STEPS TO 6.0 dB. METER
TRACKS + 1/2 SMALL DIV.

YES

NO

--------------

NOTE DC LEVEL AT Z107 PIN 6
MEASURED WITH AN OSCILL
OSCOPE EQUALS POSITIVE
AMPLITUDE OF PROCEEDING

STEP

REPLACE RESISTOR

►

PAK Z501 ON ENR
GAIN BOARD. CHECK
PLUGS AND HARNESS

PERFORM CAL CHECK PER
PAR 5-18

NO

REPLACE Z105

W1 TP107

5 V/cm
1 ms/cm
DC COUPLED
S101 AUTO

W16 TP 101, 102 TYPICAL

0.2 V/cm
1 ms/cm

DC COUPLED - OFF
S101 MANUAL

REPLACE M101. CHECK
RANGE SWITCH CIRCUIT

PERFORM GAL CHECK PER
PAR 5-18

TP 107

W1

5 V/cm

1 ms/cm
DC COUPLED

S101 AUTO

W2 TP 108

5 V/cm

1 ms/cm
DC COUPLED

S101 AUTO

W16 TP 101, 102TYPICAL

0.2 V/cm
1 ms/cm

DC COUPLED - OFFSET
S101 MANUAL

W17 Z105 PIN 12 TYPICAL

0.2 V/cm
1 ms/cm

DC COUPLED - OFFSET
S101 MANUAL

W18 Z106 PIN 8 TYPICAL

2 V/cm
1 ms/cm
DC COUPLED
S101 MANUAL

Figure 5-13. Video-DC Troubleshooting Chart

5-19

1 ms/cm
DC COUPLED

Figure 5-15. Power Supply Troubleshooting.

Chart

5-22

Figure 5-16. Power Supply, Parts Location and Schematic Diagrams

(Sheet 1 of 2)

n i/n * \ h w

i

V ''

H A «

/)/&(*£ -¿r

Ê? £'U®~££

V

. •> ‘¿“0

t.

■WHt kW

TP201

☆

0.2 V/cm
5 ms/cm

LINETRIGGER
AC COUPLED
AUTO

TP202
2m V/cm

1 ms/cm
AC COUPLED
S101 AUTO

TP203

0.2 V/cm
5 ms/cm
LINETRIGGER
AC COUPLED
S101 AUTO

TP205

0.1 V/cm
5 ms/cm
LINETRIGGER
AC COUPLED
S101 AUTO

TP204

2m V/cm
1 ms/cm
AC COUPLED
S101 AUTO

(Sheet 2 of 2)

5-23

ç

>}

¿ M M M

" a

■f- -V- ■

• ! •

&

&

Z102 PIN 8

10m V/cm
1 ms/cm

AC COUPLED
AUTO NF 3dB

Z106 PIN 10

0.2 V/cm

1 ms/cm

DC COUPLED

AUTO NF 3dB

ENR SET 15.5 dB

8 T Z103 PIN 10

5 mV/cm

1 ms/cm

AC COUPLED
AUTO NF 3dB

Z114 PIN 4
5 V/cm

1 ms/cm

DC COUPLED

TP101

0.2 V/cm

1 ms/cm

DC COUPLED

AUTO NF 3dB

TP106
5 V/cm

1 m s/cm

DC COUPLED

TP 108
5 V/cm

1 ms/cm

DC COUPLED
S101 AUTO

20 T xp 105

V/cm

1 ms/cm

DC COUPLED

Figure 5-17. IF-Video Parts Location and Schematic Diagrams

(Sheet 1 of 2)

Z114 PIN 10
5 V/cm

1 ms/cm

DC COUPLED

Z105 PIN 12

0.2 V/cm

1 ms/cm

DC COUPLED
AUTO NF 3dB
ENR SET 15.5 dB

TP 102

0.2 V/cm

1 ms/cm

DC COUPLED
AUTO' NF 3dB
ENR SET 15.5 dB

Z104 PIN 10

1 V/cm
1 ms/cm

DC COUPLED

AUTO IMF 3dB

a— aw

> — — A .

H i

---

Z115 PIN 5
5 V/cm

1 ms/cm

DC COUPLED

Z115 PIN 9
5 V/cm

1 ms/cm

DC COUPLED

17J Z115 PIN 4

5 V/cm

1 ms/cm

DC COUPLED

23T Z115 PIN 10

5 V/cm

1 ms/cm

DC COUPLED

TP107
5 V/cm

1 ms/cm

DC COUPLED
S101 AUTO

Z116 PIN 6
5 V/cm

1 ms/cm

DC COUPLED

2101 L102 L103 C109 Z102

... n

r :

1/

y

0 '

$

ohV V

*

V

* 3

á 0 M £ít<H b

C c 'íit ’J

't.ü -

. .

>16>— (6<rr~

•,7> -< 7^ r

Figure 5-17. IF-Video Parts Location and Schematic Diagrams

(Sheet 2 of 2)

5-25/5-26

=RONT PANEL
¡INSIDE VIEW)

LOW

METER

SCALE

HIGH

n .

11

CD

in

SYSTEM

ENR 53

co
(N

c/j

REAR PANEL

CD
CD

CO
CO

(INSIDE VIEW)

ö o

6

1

o

P6 L

ENR GAIN

BOARD

Ô

8 9

7

2

3

P

o o

°?

in

ON

OFF

DL1

(ON/ÖFF LAMP)

o

o

10

4

5

P3

e'b

-12 V DC

.NOISE MOD IN

+12VDC

GND-OVDC

----------------------

-o

6
1 2

-o

KEY

3

p

c

< f ■

/— -\

<5 3 8 o

c/» '° o

O o

9

8

3

4

o

?

GND CHASSIS

o

10

P2

5

o

S11A-3

F1-1

P5-20

P5-2

J7

P9ry

__

_ C T ^

POWER SUPPLY BOARD

P4-1

P4-20

P4-3

/•

S11B-6

S11A-3

S11B-5 -----------------------

S11A-2

P4-5

*9

CM
GO

CD

rsi

Zi
Q

CO
CO

D -

P10 ^ —

P9 -+—

GND —

P4-9 —

P4-8 -m—

P4-7 —

P4-6 —

P4-15 • * —
P4-16 —

P4-17

P4-18 -rt—

I

s u b -6 --------------------------

S11A-3 --------------------------

S11B-5 -«

S11A-2

P4-1

P4-20

P4-3

P4-5

-12V DC

NOISE MOD IN

+12VDC

GND-O V DC

--------------------------

- O

- O

6
1 2

P3

< f \ e \ )

—{J * ' { J

— u u

_ c f e , 9V

- 0 5 tO ih

KEY

I

O O

8

7

3 4

A J

O 0

5

O O

GND CHASSIS

P2-2

P2-6

S1-3

P2-1

P2

P2-7

F2-1

S1-2 ■

S11B-6 ■

A

t ~ r

IF IN PUT

J8

<

NOISE

SOURCE

O 1
O 2
03

04

O 5

06
O 7
O 8

09
Oio

On
012

130

140

150
160

170
180

190
200
210

220

2 3 Q

CM

0

1 2 3 0 V

S11A

NOISE J

FIG UR E / mo ^

AL AR M ^

R E LA Y ^ NC

SIG NA L M ON ITO R

SIG N A L G N D -----

EXT. M E T ER (-)

EXT. ME T E R (+)

RECO R DER O U T P U T-* -----

----------

----------

-----

----------

----

O 1 130

-02

-O3

-O4

-05

-06

140
150

160
170

180

-O? 190

-08

2 0 0

0 9 21Q

to

to

o

o

230

0 1 1

0.12 24Q

o

LINE
FILTE R

FUSES

Figure 5-18. Wiring Diagram

,5-27/5-28

?

CHAPTER VI

SPARE PARTS

6-1. GENERAL

The System Noise Monitor is intended to be maintained by the replacement of defective
modules. All subassemblies are modularized and easily replaceable, by design for accessibility and
utilization of modern interconnecting hardware. Use of troubleshooting procedures and test points
can easily identify faulty subassemblies.

6-2. RECOMMENDED SPARE PARTS

Based on reliability and maintainability aspects of design, the following spare parts are
recommended for stock at each site for a low quantity of System Noise Monitors;

AILTECH

Item Description

IF Video PC Board

Power Supply PC Board 298021-1

Part Number

System ENR Gain PC
Board

S3

M l

FI, 2

DL1

DL2 Lamp, Incandescent

6-3. REPLACEABLE SPARE PARTS

For connector housing service, use Connector Tool supplied by Amp, part number 91084-1.

Switch, Thumbwheel

Meter

Fuse, 1/8 amp
(230 VAC connection)
Fuse, 1/4 amp
(115 VAC connection)

Lamp, Incandescent

289172-1

299493

298293-2*

990019-4

990019-23

293156

293155

6-1

Main Chassis

Item

DL1
DL2

F1,F2

FL1

J1

J7, J8

M l

M IA

PI
P2, P3
P4, P5
P6
P9, P10

Description

Lamp, Incandescent
Lamp, Incandescent

Fuse, 1/8 amp

(230 VAC connection)

Fuse, 1/4 amp

(115 VAC connection)

Filter, EMI

Jack, Panel, Multipin
Jack, Panel, BNC

female

Meter, Panel, noise

figure

Meter, Panel, noise

temperature

Plug, Cable, Multipin
Housing, Plug, 10 Pin
Housing, Plug, 20 Pin
Housing, Plug, 10 Pin
Connector, Plug,

Coaxial Cable

Manufacturer

Manufacturer Part Number

Data Display

Data Display

Corcom

Cinch 57-40240

Cinch
Amp
Amp
Amp
Phelps-Dodge

44D57-R0
44D57-G0

1EF1

UG-1094A/U

57-30240
87133-5
87133-6
87133-5
700156

AILTECH
Part Number

293156
293155

990019-4

990019-23

293600

294349
294334

298293-2

298254*

294346
299951
299952
299951
294392

51

52

53

S ll

* Applicable only to units with noise temperature readout.

Switch, Paddle,

DPDT

Switch, Rocker,

DPDT

Switch, Thumbwheel

Switch, Slide, DPDT

Line Cord, 3 Conductor

6 Ft.

C&K Components

C&K Components

Interswitch

Switchcraft

Corcom

7201-J60

7201-J50

IS0905

462561FR

80-1245

294530

294529

299493

294539

294948

6-2

IF VIDEO PC BOARD (10MHz - 40 MHz) Part Number 298020-1

___

_____________________(40 MHz — 80 MHz) Part Number 298020-4

Item Description

C101 Capacitor, 0.01 nF, 50V TRW
C102 Capacitor, Variable, Erie

15-60 pF

C102A

C103
Cl 04 thru Capacitor, 0.001 ¡xF CRL DD102

C106
Cl 07 Not Used
Cl 08 thru Capacitor, 0.001 fiF

C113
C114,

C114A
C115, Capacitor, 0.001 /xF

C116
C117 Capacitor, 470 pF

( C118 Capacitor, 0.001 juF

C119 Capacitor, 0.01 juF, 50V
C120
Cl 21 Capacitor, 470 pF
C122 Capacitor, 0.001 fi F
C123
C124,

; C125

C126

C127 Capacitor, 0.1 juF 50V
Cl 28 Capacitor, 0.001 juF
C129, Capacitor, 0.1 ai F 50V

C130
C131
C132
C133
Cl 34 Capacitor, 1 fxF, 16 V Sprague TE1148 293881

| C135 Capacitor, 10 juF, 16V Sprague

C136
C137 Capacitor, 50 ju F, 16V Sprague TE1160 293884
C138 Capacitor, 2200 pF

! C139

thru

C141
Cl 42 Not Used
Cl 43 Capacitor, 10 pF El Meneo
C144

- C145
C146 Not Used

Capacitor, Variable,

1.9-15.7 pF

Capacitor, 0.1 juF 50V

Capacitor, Variable

15-60 pF

Capacitor, 0.001 ¡xF

Capacitor, 0.01 juF, 50V
Capacitor, 25 ¡jlF, 16V

Capacitor, 0.001 nF

Capacitor, 10 p.F, 16V
Capacitor, 0.01 nF, 50V TRW

Capacitor, 0.047 fiF

Capacitor, 2.25 /i F

Capacitor, 0.001 ¡jlF

Not Used
Not Used

Manufacturer

E. F. Johnson

TRW

CRL DD102 293804

Erie 538011-F15-60

CRL

El Meneo DM15-471J 293840
CRL
TRW
CRL
El Meneo DM15-471J 293840
CRL
TRW
Sprague

CRL
TRW
CRL
TRW

Sprague

TRW 601PE-.047

Sprague

CRL

Manufacturer
Part Number Part Number

601PE-.01

538-011-F15-60 293747*

187-0109-005

601PE-.1

DD102 293804

DD102 293804
601PE-.01
DD102 293804

DD102
601PE-.01
TE1157.1

DD102
601PE-.1
DD102 293804
601PE.1

TE1155
601PE-.01

TE1155
CSR13BE225K 293792

CK06BX-222K 299873-222
DD102 293804

DM5-100J

AILTECH

115285-6

293728#

115285-15
293804

293747 ,

115285-6

293804
115285-6
293883

293804

115285-15

115285-15

115307-16
115285-6
115285-14

115307-16

299241-100

*Used on 298020-1 only

#Used on 298020-4 only

6-3

Item

Description

IF VIDEO PC BOARD (continued)

Manufacturer

Manufacturer AILTECH

Part Number

Part Number

C147 Capacitor, 0.1 /uF 50V TRW 601PE-.1
C148
C149
Cl 50
Cl 51 thru

C153

Cl 54

CR101

CR102

J10 Jack, PC Board,

L101 thru

L l ll
L112
L113

Q1 0 1

R101 Resistor, 100 S2,1/4 W
R101A
R102 Resistor, 5.1 K, 1/4 W
R103
R104
R105 Resistor, 10 K, 1/4 W
R106 Resistor, 510 Î2,1/4 W RC07GF511J
R107
R108, Resistor, 6.2K, 1/4 W

R109
R110
R ill
R112,

R113

R114

R115

R116 Resistor, 10K, 1%,

R117
R118 thru

R121

R122

NotUsed

NotUsed
Capacitor, 2 nF, 25V Sprague

Not Used
Capacitor, Variable,

15-60 pF

Diode, Semiconductor,

Zener

Diode, Semiconductor

Coaxial, Female

Inductor, 14 juH Delevan

Not Used
Inductor, 0.22 ßH

Transistor

Resistor, 51 Î2,1/4 W

NotUsed ...
Resistor, Variable, 100 £2

Resistor, 10K, 1/4 W RC07GF103J
Resistor, IK, 1/4 W
Resistor, 3.9K, 1/4 W

Resistor, 10K, 1%,

1 / 8 W

Resistor, 100K, 1/4 W

1/8 W
Resistor, 100K, 1/4 W
Resistor, IK, 1%, 1/8 W

Resistor, 7.5K, 1/4 W RC07GF752J

Erie

Phelps-Dodge 700214

Delevan , 1850-04

Bourns

TE1201

538-011-F15-60 293747

1N936

1N4009 293201

1840-34

2N4123 294150

RC07GF101J 299701-101*
RC07GF510J 299701-510#
RÇ07GF512J 299701-512

3009P-1-101 299722
RC07GF103J 299701-103

RC07GF622J

RC07GF102J 299701-102
RC07GF392J 299701-392

RN60C1002J 299709-421

RC07GF104J 299701-104
RN60C1002J

RC07GF104J 299701-104
RN60C1001F

115285-15

293885

293241

294396

115297-2

299237-04#

299701-511*

299701-622

299701-103

299709-421

299709-322

299701-752

*Used on 298020-1 only

#Used on 298020-4 only

6-4

IF VIDEO PC BOARD (continued)

Manufacturer

Item

R123

R124
R125
R126

R127

R128

R129

R130
R131
R132,

R133

R134,

R135
R136 Resistor, 1K, 1/4 W
R137
R138
R139 Resistor, 1.6K, 1/4 W
R140 Resistor, Variable, 1K
R141 Resistor, 1.2K, 1/4 W
R142
R143 Resistor, 8.2K, 1/4 W
R144 Resistor, 4.3K, 1/4 W

R145
R146

R147, Resistor, 10K, 1/4 W

R148

R149 Resistor, 200K, 1%,

R150 Resistor, Variable, 10K
R151 Resistor, 10K, 1/4 W
R152 Resistor 1M, 1/4 W

R153 Resistor, 10 £2, 1/4 W
R153A Resistor, 15 £2,1/4 W
R154 Resistor, 10 £2 ,1/4 W

R154A
R155
R156
R157 Resistor, Vairable, 5K
R158
R159
R160 Resistor, 1K, 1%, 1/8 W RN60C1001F
R161

Description

Resistor, 1%, 1/8 W

Resistor, Variable, 5K
Resistor, Variable, 20K
Resistor, 100 £2 ,1%,

1/8 W

Resistor, 7.50K, 1%

1/8 W

Resistor, 300 £2 ,1%,

1/8 W

Resistor, 80.6K, 1%,

1/8 W
Resistor, 10K, 1%, 1/8 W
Resistor, 51K, 1/4 W

Resistor, 100 £2 ,1%,

1/8 W
Resistor, 20K, 1%,

1/8 W

Resistor, 100K, 1/4 W
Resistor, 1K, 1/4 W

Resistor, 4.3K, 1/4 W

Resistor, 1K, 1/4 W
Resistor, 820K, 1/4 W

1/8 W

Resistor, 15 £2,1/4 W

Not Used

Resistor, 2.2K,1/4W

Resistor, 3K, 1/4 W

Resistor, Variable, 5K

Manufacturer

Value Selected At
Test
Boums

Boums 3279W-1-203

Boums

Boums

Boums 3279W-1-502 294091

Boums

Part Number

RN60CXXXXF

3279W-1-502

RN60C1000F

RN60C7501F

RN60C3000F

RN60C8062F

RN60C1002J
RC07GF513J
RN60C1000F

RN60C2002F

RC07GF102J

RC07GF104J
RC07GF102J
RC07GF162J
3279W-1-102 299777
RC07GF122J 299701-122
RC07GF432J 299701-432
RC07GF822J
RC07GF432J
RC07GF102J
RC07GF824J
RC07GF103J

RN60C2003F

3279W-1-103
RC07GF103J
RC07GF105J
RC07GF100J
RC07GF150J 299701-150#
RC07GF100J
RC07GF150J

RC07GF222J
RC07GF302J

3279W-1-502

AILTECH
Part Number

299709-XXX

294091
294090
299709-219

299709-409

299709-667

299709-512

299709-421
299701-513
299709-219

299709-332

299701-102
299701-104
299701-102
299701-162

299701-822
299701-432
299701-102
299701-824

299701-103

299709-547

299778
299701-103
299701-105

299701-100*

299701-100*
299701-150#

299701-222
299701-302
299709-322

294091

*Used on 298020-1 only

#Used on 298020-4 only

6-5

IF VIDEO PC BOARD (continued)

Item

R162, Resistor, 10K, 1/4 W

R163

R164

R165

R166
R167
R168
R169
R170

R171
R172
R173,

R174

S101, Switch, 14 Pin, DIP

S102

T101
T102
T102A

Description

Resistor, 6.04K, 1%,

1/8 W

Resistor, 10K, 1%,

1/8 W
Resistor, 10K, 1/4 W
Resistor, 51K, 1/4 W

Resistor, 510 £2,1/4 W
Resistor, Variable, 2K
Resistor, 4.02K, 1%,

1/8 W

Resistor, 7.5K, 1/4 W
Resistor, 10K, 1/4 W RC07GF103J
Resistor, 82.5K, 1%,

1/8W

Transformer

Transformer Magnético
Transformer Magnético

Manufacturer

Bourns

Minelco

Magnético

Manufacturer
Part Number

RC07GF103J

RN60C6041F 299709-400

RN60C1002J

RC07GF103J
RC07GF513J
RC07GF511J
3279W-1-202 299779
RN60C4021F

RC07GF752J

RN60C8252F

SW40-1142

12572
12419
12420

AILTECH
Part Number

299701-103

299709-421

299701-103
299701-513
299701-511

299709-380

299701-752
299701-103
299709-510

294503

298730
294809*
294810#

Z101,

Z102

Z103

Z104, Integrated Circuit

Z105
Z106
Z107 Integrated Circuit
Z108
Z109
Z110
Z l l l
ZÍ12
Z113
Z114

Z115,

Z116
Z117 Integrated Circuit

sUsed on 298020-1 only
^Used on 298020-4 only

Integrated Circuit

Integrated Circuit

Integrated Circuit

Integrated Circuit
Integrated Circuit
Integrated Circuit
Integrated Circuit
Integrated Circuit
Integrated Circuit
Integrated Circuit
Integrated Circuit

Motorola

Motorola
Signetics

RCA
Signetics
RCA
Signetics
RCA
Signetics
RCA
Signetics
RCA
RCA

Signetics UA747CA

MC1350P

MC1496L 293498
UA747CA

CD4016AE 293381

' UA747CA

CD4016AE 293381
UA747CA
CD4016AE 293381
UA747CA
CD4016AE 293381
UA747CA
CD4049AE
CD4000AE

293395

293484

293484

293484

293484

293484
293384
293376

293484

6-6

POWER SUPPLY PC BOARD ASSEMBLY

Part Number 298021-1

Item

C201
C202 Capacitor, 1000 /xF, 25V
C203
C204
C205
C206
C207
C208
C209
C210

CR201,

CR202

J2, J3
J4 thru

J8

J9

P2,P3
P4 thru

P8

P9

Description

Capacitor, 10 /uF, 16V

Capacitor, 0.001 nF
Capacitor, 0.1 juF
Capacitor, 10 /xF, 16 V
Capacitor, 500 /xF, 25V
Capacitor, 0.1 juF

Capacitor, 0.01 /xF

Capacitor, 250 nF , 50V
Capacitor, 100 pF

Rectifier, Bridge

Connector, Post

Not Used

Jack, P.C. Board,

Coaxial

Housing, Plug, 10 Pin

Not Used

Plug, Coaxial

Manufacturer

Manufacturer

Sprague
Comell-Dubilier BR1000-25
Centralab
Centralab DDA-104
Sprague
Comell-Dubilier BR500-25
Centralab DDA-104
Sprague
Comell-Dubilier BR250-50
Centralab DD101

General Instrument

Amp

Phelps-Dodge 700209

Amp

Phelps-Dodge 700156

Part Number

TE1155

DD-102

TE1155

5HKS-S10

W02M

86091-2

87133-5

AILTECH

Part Number

115307-16
293763
293804
293820
115307-16
293762
293820
299244
293761
293803

294768

293079

294395

299951

294392

Q201,

Q2 0 2

R201

R202
R203
R204

R205

R206,

R207

R208

R209

R210

R211
R212 Resistor, 10 £2,1/4 W
R213
R214 Resistor, 6.81K, 1%,

Transistor

Resistor, 2 £2,1/2 W
Resistor, IK, 1/4 W
Resistor, 10K, 1/4 W
Resistor, 14K, 1%,

1/8 W
Resistor, Variable, 5K
Resistor, 6.81K, 1%,

1/8 W
Resistor, 16.9K,

1/8 W
Resistor, 2 £2,1/2 W
Resistor, 15K, 1/4 W
Resistor, 2K, 1/4 W

Résistor, 5.IK, 1/4 W

1/8 W

1%,

2N4123

RC20GF2R0J

RC07GF102J
RC07GF103J
RN60C1402F

Weston

502-005-5K
RN60C6811F

RN60C1692F

RC20GF2R0J
RC07GF153J
RC07GF202J
RC07GF100J
RC07GF512J
RN60C6811F

294150

299702-000
299701-102
299701-103
299709-435

294091
299709-405

299709-443

299702-000
299701-153
299701-202
299701-100
299701-512
299709-405

6-7