Agilent Technologies 6571A, Service Manual

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Diagrams
Table 6-3. Troubleshooting Test Points (continued)
TEST POINT
No. & Loc.
Signal Tested Measurement and Conditions
A4 AC Input Board
-C307 +15 Vp primary bias common Connect meter or scope common here. Then make
measurements at test points
through .
R317 +15 Vp primary bias
+15
±
0.9V
+C352 +26V +24.4V to +28.6V
-C315
Secondary common Move meter or scope common here. Then make
measurements at test points
through .
R333 +5V secondary bias +5
±
0.2V
R331 +15V
s
secondary bias
+15
±
0.9V
+C353 +26V +24.4V to +28.6V
R330 -15V
s
secondary bias
-15
±
0.9V
+C354 -25V -22.5V to -27.5V
U310-6 RELAY ON* 0V
U308-6
RESET
0V
U308-7 BIAS OK +5V
U308-1
PREF
+2.5V
U308-5 RESET* Held low for approximately 50 ms at power-on, then goes
high.
U311-7
FAN DETECT
+3V
D317 -25V +3V
U311-2
FAN_PWN
+0.6V
A3 FET Board
Note:
Test points through are on the A3 FET Board. Troubleshooting procedures at these
points are given under Dynamic Troubleshooting section of the FET Troubleshooting Chart
(Table 3-4).