HP 8560A Service Manual page 62

4. IF Amplitude Adjustments
A5 Reference Attenuator Adjustment
12. Set the HP 3335A (AMPLITUDE) to -60 dBm.
13. Connect a BNC cable between the
INPUT 500.
14. On the HP 856OA, press (CAL) and
keys to place the peak of the displayed signal 3 dB to 5 dB below the reference level.
On the HP 8560A press
level to -10 dBm.
16. Change the HP 3335A (AMPLITUDE) to -10 dBm.
17. On the HP 8560A press ICAL).
18. Note the AMKR amplitude. Ideally, it should read 50.00 dB +/-.l dB.
19. If the AMKR amplitude is less than 49.9 dB, rotate A5R343 (15 dB ATTEN) one-half
turn counterclockwise for each 0.1 dB below 50.00 dB. If the AMKR amplitude is greater
than 50.1 dB, rotate A5R343 one-half turn clockwise for each 0.1 dB above 50.00 dB. Do
not adjust A5R343 more than five turns before continuing with the next step.
20. On the HP 8560A press
22. Repeat steps 12 through 21 until the AMKR amplitude reading is 50.00 dB +/-.l dB.
A5 Adjustment Verification
23. On the HP 856OA, disconnect W29 from A5J3. Connect the test cable between A5J3 and
the 50 R output of the HP 3335A.
24. Set the HP 8560A reference level to -10 dBm.
25. Set the HP 3335A [n) to -5 dBm.
27. The MARKER amplitude should read -10 dBm +/-.13 dB. If the reading is outside of
this range, repeat steps 4 through 21.
28. On the HP 8560A, reconnect W29 to A5J3. Press (PRESET) and set the controls as follows:
C E N T E R F R E Q
SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 Hz
REF LVL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1OdBm
RES BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300kHz
29. Connect a BNC cable between the HP 8560A CAL OUTPUT and INPUT 500.
30. On the HP 8560A, press [E) (CAL) and
31. Use the knob or step keys to adjust the REF LEVEL CAL setting until the MKR reads
-10.00 dBm +/-.l dB.
32.
On the HP 8560A, press
2-28 Adjustment Procedures
50
REF LEVEL ADJUST.
MARKER DELTA.
[ ]
and
PEAK SEARCH
ADJ CXJRR IF STATE.
MARKER NORMAL.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..300MHz
REF LVL ADJ .
STORE REF LVL .
Use the front-panel knob or step
Set the analyzer reference
Note the AMKR amplitude reading.
MARKERS OFF .