HP 3325A Calibration Manual page 22

TB 9-6625-2049-35
Figure 5. Power supply assembly A2 – test instrument top view.
(5) Press presently active FUNCTION key to remove ac output and activate
ENTRY DC OFFSET key (lit).
(6) Enter 0 VOLT using DATA keys and press AMPTD CAL key.
(7) Connect multimeter INPUT HI to TP AMP OUT (fig. 3) and LO to circuit board
ground.
The voltages measured in (1) through (3) above may be
adjusted out of tolerance by (8) through (11) below. This is not
a cause for concern.
(8) Adjust R40 (fig. 3) until digital multimeter indicates less than 5 mV dc (R).
(9) Connect multimeter INPUT HI and LO to TI SIGNAL.
feedthrough termination.
(10) Enter 5 VOLT using DATA keys.
(11) Press AMPTD CAL key. Adjust R22 (fig. 5) until multimeter indicates 10.000
V dc.
(12) Enter -5 VOLT using DATA keys.
(13) Multimeter will indicate between -9.985 and -10.015 V dc.
21. Final Procedure
a. Deenergize and disconnect all equipment.
b. Annotate
22
and affix DA
NOTE
label/form in accordance
Do not use 50
with TB 750-25.