Troubleshooting 37
YES
NO
NO
NO
NO
YES
YES
YES
START
"DAC DEFECTIVE"
TURN OFF SUPPLY AND REMOVE TOP COVER.
TURN ON SUPPLY AND CHECK BIAS AND
REFERENCE VOLTAGES (TEST POINTS 9
THOUGH 22 . (SEE TABLE 6-3*).
* IF THE SUPPLY FAILS SELF TEST, TURN OFF
THE SUPPLY, DEPRESS THE 7 KEY AND THEN
SO AS TO SKIP SELF TEST.
ARE
VOLTAGES
OK?
PROBABLE DEFECTIVE A6 BOARD
SHORT A10U506-1 (SA MODE) TO A10U506-20 (COM),
SEE FIG. 3-15. TURN ON SUPPLY AND WAIT TWO
SECONDS THEN REMOVE SHORT. WAIT FOR "POWER
ON INIT" TO COMPLETE. USE A SCOPE TO CHECK
THE CV DAC (A10U513-6), CC DAC (A10U514-6) AND
READBACK DAC (A10U515-6) OUTPUTS. COMPARE
THE WAVEFORMS GIVEN IN FIG 6-1.
IS ONE
DAC MISSING
STEPS?
ARE ALL
DACS MISSING
STEPS?
IS
CV OR CC DAC
DEFECTIVE?
NO
YES
CHECK REF VOLTAGE FOR CV/CC DACS AT
A10U504-6 37 WITH RESPECT TO 36 .
DOES A10U504-6
= 10V?
THE WAVEFORMS TAKEN AT THESE POINTS WITH
TURN IT ON WHILE HOLDING THE KEY DOWN
PROBABLE DEFECTIVE A10 BOARD
PROBABLE DEFECTIVE A10 BOARD
PROBABLE DEFECTIVE A10 BOARD
PROBABLE DEFECTIVE A10 BOARD
PROBABLE DEFECTIVE A10 BOARD
Figure 3-7. DAC Circuits Troubleshooting)
Summary of Contents for 669 A Series
Page 2: ...Service Manual Keysight Series 669xA GPIB DC Power Supplies ...
Page 3: ......
Page 27: ......
Page 56: ...Troubleshooting 53 Figure 3 15 3 Inch Front Panel Frame Assembly ...
Page 57: ...54 Troubleshooting Figure 3 16 Assembly A10 Exploded View ...
Page 58: ...Troubleshooting 55 Figure 3 17 Assembly A10 Exploded View 6690A ...
Page 59: ...56 Troubleshooting Figure 3 18 Assembly A10 Exploded View 6691A 6692A ...
Page 60: ...Troubleshooting 57 Figure 3 19 Three Phase Line Choke Subchassis Wiring ...
Page 61: ...58 Troubleshooting Figure 3 20 24 Volt Fan Transformer ...
Page 77: ...74 Diagrams Figure 6 1 Test Point Waveforms for Table 6 3 sheet 2 of 2 ...
Page 79: ...Figure 6 3 A1 Front Panel Board Assembly Diagram ...
Page 81: ...Figure 6 5 A2 GPIB Board Component Location ...
Page 83: ...Figure 6 7 A3 FET Board Component and Test Point Location ...
Page 87: ...Figure 6 11 A4 AC Input Board Component and Test Point Location 12 9 10 11 ...
Page 89: ...Figure 6 13 A5 DC Rail Board Component and Test Point Location 13 14 ...
Page 91: ...Figure 6 15 A6 Bias Board Component and Test Point Location 15 16 17 18 19 19 20 22 ...
Page 94: ...Figure 6 17 Power Mesh Schematic Diagram All Models ...
Page 103: ......