AR 10044778, Operating And Service Manual, Page: 48 / 54

Model 100U1000
30 Rev B
3. After checking for safety, try to clear the Interlock Fault from the front panel by using the RESET switch.
4. If the Interlock Fault will not clear, check for continuity in the External Interlock Circuit (Pin 1 to Pin 8
in the connector, which mate with J3 in the rear panel).
5. Check the voltage on A12 J5, pin 30; it should be < 0.1V.
6. If the voltage on A12 J5, pin 30 is high, check the interlock line to ground.
4.3.5 Amplifier Faults (Schematic Diagram Nos. A2 – 10042781 and
10041561; A6, A7 - 10042997 and 10044724)
1. The fault output of the A2, A6 and A7 modules is sensed on A12, J5, pins 9, 12 and 13.
2. Verify the correct voltages to the modules. Troubleshoot any incorrect voltages.
FL50 = +28 ± 0.2V
FL51 = –15 ± 0.2V
4.3.6 Low or No Power Output (DC Tests) (Schematic Diagram No.
10041189, 10044724)
All indicators are normal, the front panel display reads Power On , and the cooling fan (B1 and B2) are
operating.
1. Check the position of the RF Gain control—is it set to maximum gain?
2. Check the RF input to the unit—is it the correct amplitude and frequency?
3. Check the RF output connection from the unit—is it correctly connected to the load?
Is the coaxial cable okay?
4. Check the following voltages on the Power Supply. If any of the voltages are out of tolerance, correct
them before further troubleshooting.
PS1 J18 Pin 5
+15 V
±
0.5 V
PS1 J18 Pin 8 -15 V
±
0.5 V
5. Check the voltage on the feed thru caps of the A1 Pre-Amp, with the RF gain control at maximum gain.
Troubleshoot any incorrect voltages.
FL2
+24 V
±
0.5 V
FL3 -15 V
±
0.5 V
FL4 +4.7 V
±
0.5 V
6. Check the voltages on the feed-thru caps of A2, A6 and A7.
FL50 +28.0 V
±
0.3 V
FL51 –15.0 V
±
0.3 V