HP 8568B, Performance Tests And Adjustments Manual, Page: 184 / 313

6. Video Processor Adjustments
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Set step attenuator to 120 DVM indication should be 0.000
V dc. (If DVM indication is out of tolerance, adjust
ZERO on the log amplifier-detector board..)
Set step attenuator to 0
Key in and adjust DATA knob for DVM indication as
close to + 1.000 V dc as possible. (It may be necessary to
slightly adjust the front panel AMPTD CAL control to achieve
required tolerance.)
Connect DVM to
Adjust OS for a DVM indication of 0.000 Vdc.
See Figure 3-36 for
the
location of the adjustment.
P r o c e s s o r F S Z E R O
Figure 3-36. Location of Video Processor Adjustments
Connect the DVM to
Set the step attenuator to 120
Adjust ZERO for a DVM indication of 0.000 Vdc.
Set the step attenuator to 0
Adjust FS for DVM indication of 0.001 V dc.
Repeat steps 12 through 15 until specifications of steps 13 and 15
are met.
LOG Offset Adjust
17. Set step attenuator to 40
18. Key in
LOG
(ENTER
(SHIFT)
L E V E L
]
-50
19. Connect DVM to Record DVM indication. Indication
should be approximately V dc.
V de
20. Decrease reference level to -60 using the step key.
21. Adjust LG OS for DVM indication of V
dc greater than the DVM indication recorded in step 19. See
Figure 3-36 for location of adjustment.
Adjustments