HP 8560A, Service Manual

Page: 57 / 450

3. IF Adjustment
Note If the range for the XTAL CTR adjustment is insufficient, replace the
appropriate factory-selected capacitor as listed in Table 2-8. To determine
the correct replacement value, center the XTAL CTR adjustment, and press
ADJ CURR IF STATE.
After the
IF ADJUST STATUS
message
the DVM display. Choose a capacitor value from Table 2-9, based on the
DVM reading and the presently loaded capacitor value. Table 2-10 lists a few
capacitor part numbers.
Caution
Set the HP 8560A switch off before removing or replacing any shield.
18. Move the positive DVM test lead to
19. Adjust XTAL CTR 2 using the procedure in steps 15 through 17.
20. Move the positive DVM test lead to
21. Adjust XTAL CTR 3 using the procedure in steps 15 through 17.
22. Move the positive DVM test lead to
23. Adjust XTAL CTR 4 using the procedure in steps 15 through 17.
Table 2-8. Factory-Selected XTAL Filter Capacitors
XTAL CTR Adjustment Fixed Factory Select Capacitor
XTAL CTR
1
XTAL CTR 2
XTAL CTR 3
XTAL CTR 4
Table 2-9. XTAL Factory-Selected Capacitor Selection
DVM Reading (V)
Currently Loaded Capacitor Value
Replace Replace Replace Replace Replace Replace
15 with:
18
with: 20 with: 22 with: 24 with: 27 with:
0 to 1.5
* * * * *
1.5 to 2.5 27 * * * *
2.5
to 3.5
22 27 27
* * *
3.5 to 4.5 18 22 24
27 27 *
4.5 to 5.5 18 20 22 24 27 *
5.5
to 6.5 no change no change no change no change no change no change
6.5
to 7.5 no change no change no change no change no change no change
7.5
to 8.5 *
15 18 18
22 24
8.5
to 9.5 *
15 15 18
20 24
9.5 to 10 * * 15
18 20 24
* Indicates a condition that should not exist; suspect broken hardware.
Adjustment Procedures 2-23