Teledyne T703U VCR User Manual


 
Teledyne API T703/T703U Calibrator Operation Manual General Troubleshooting & Service
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8.4.3. DC POWER SUPPLY
If you have determined that the calibrator’s AC mains power is working, but the unit is
still not operating properly, there may be a problem with one of the instrument’s
switching power supplies. The supplies can have two faults, namely no DC output, and
noisy output.
To assist tracing DC Power Supply problems, the wiring used to connect the various
printed circuit assemblies and DC Powered components and the associated test points on
the relay PCA follow a standard color-coding scheme as defined in the following table.
TP1 TP2 TP3 TP4 TP5 TP6 TP7
DGND +5V AGND +15V -15V +12R 12V
Figure 8-4: Location of DC Power Test Points on Relay PCA
Table 8-6: DC Power Test Point and Wiring Color Codes
NAME TEST POINT# TP AND WIRE COLOR
Dgnd
1
Black
+5V
2
Red
Agnd
3
Green
+15V
4
Blue
-15V
5
Yellow
+12R
6
Purple
+12V
7
Orange
07223C DCN6572