Table of Contents
Advertisement
Table 5-6.
System Troubleshooting (Cont)
Test Paragraph
Fault
, Troubleshooting Procedure
5-144
No spectrum
analyzer sweep
1. Check pin 6 of the RF Synthesizer module
(AS) for a 50 Hz square wave. If not present
replace the RF Synthesizer module.
2. If 50 Hz signal is present replace the Scope/
DVM Control module (A3).
5-144
Spectrum display is in error
1. Replace the Receiver module (A4).
5-145
No duplex output
1. Replace the RF Input module (A11).
Table 5-7.
Test Point Identification
All test points are located near the top edge of the card and counted from left to right when facing the
component side of the card.
Module
Test Point No.
Signal Description
A2
1
Horizontal Amp Input
Scope Amplifier
2
Horizontal Deflection Plate
3
Horizontal Deflection Plate
4
Vertical Amp Input
5
Focus Tracking Voltage
6
Vertical Deflection Plate
7
Vertical Deflection Plate
8
Z-Axis Modulator Output
9
Intensity Tracking Voltage
10
Time Base Output
A3
1
Vertical Character Sync
Scope/DVM
2
Negative Peak Detector Output
Control
3
Gen Carrier Plus AM Level
4
Positive Peak Detector Output
5
Demodulated Calibrated Audio
6
Not Used
7
Ground
8
Multiplexed A/D Signal
9
Character Generator Reset
10
Ground
11
-8VDC
12
+8VDC
A6
1
Synth/DPL Audio
Audio Synthesizer
2
DPL Clock
3
Unfiltered DPL
5-42
. .
Advertisement
Chapters
Table of Contents
