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A2Q3 (emit)
≈
20V pk, 5
µ
s pulses, 45KHz
A2U5 (OUT)
2.5 Vdc
A2R50, A2CR11 (anode)
≈
0 >V > 0.007Vdc
A2R46, A2R47
2.5 Vdc
To check if load on + 5V is shorted, remove jumper A2W3
+15V On A2 Control Board. Voltage regulator A2U12 regulates the voltage across resistor A2R29 to be 1.25Vdc. That
sets the current through zener diode A2VR1 at 7.5mAdc. The output voltage is 1.25Vdc plus 11.7Vdc across A2VR1 plus
the voltage across A2R34.
Circuit Included. +15Vdc bias supply circuitry from connector pin A2P1-27 through test point A2J3-2 on A2 control
board.
Setup. The Main Troubleshooting Setup, Page 48. Apply the ac mains voltage to the isolatlon transformer, and set the
external supply to 0Vdc.
Input:
NODE
MEASUREMENT
SOURCE
A2U12(IN)
A2C17 (+)
≈
24Vdc
A1U1, A1C1 (+)
Outputs:
NODE ( + )
NODE (-)
MEASUREMENT
A2U12 (OUT)
A2U12 (ADJ)
l.25Vdc
A2U12 (cath.)
A2U12 (anode)
11.7Vdc
A2VR1 (anode)
A2R34, A2R33
2.05Vdc
A2LR3 (cath.)
A2VR3 (anode)
6.2Vdc
To check if load on +15V is shorted, remove jumper A2W1.
Summary of Contents for 6038A
Page 4: ......
Page 8: ......
Page 34: ...34 Figure 3 1 Troubleshooting Isolation ...
Page 35: ...35 Figure 3 1 Troubleshooting Isolation continued ...
Page 37: ...37 Figure 3 3 Clock and Primary SA Waveforms ...
Page 40: ...40 Figure 3 4 Readback and Secondary SA Waveforms ...
Page 56: ...56 Figure 3 7 Waveforms ...
Page 62: ...62 Figure 4 1 HP IB Block Diagram ...
Page 65: ...65 Figure 4 2 Front Panel Block Diagram ...
Page 90: ......
Page 93: ...93 Figure 6 1 Top View Top Covers Removed ...
Page 94: ...94 Figure 6 2 Main Board A1 Component Location ...
Page 95: ...95 Figure 6 3 Control Board A2 Component Location ...
Page 96: ...96 Figure 6 4 Front Panel Board A3 Component Location ...
Page 97: ...97 Figure 6 5 Power Mesh Board A4 Component Location ...
Page 98: ...98 Figure 6 6 HP IB Board A8 Component Location ...
Page 105: ...105 Figure 3 1 Troubleshooting Isolation option 001 ...
Page 106: ......