HP 8568B, Performance Tests And Adjustments Manual, Page: 180 / 313

5. Log Amplifier Adjustments
4. Connect DVM to and DVM ground to the IF casting.
Connect the frequency synthesizer to the RF INPUT. Key in
80 MHz and
[
AMPLITUDE
)
-86.98 The frequency
synthesizer will now provide a load.
Offset Adjustment Check
5. Adjust ZERO for 0.0000 V dc. See Figure 3-34
for location of adjustment.
Z E R O - 1 2 LG 20
L O G L O G A M P L I F I E R -
F I L T E R D E T E C T O R
LG 10 CTR AMPTD
Figure 3-34. Location of Log Amplifier Adjustments
Filter Center Adjustment
6. Press LOG
(
ENTER
7. Set the frequency synthesizer for 7.6000 MHz at output
level.
8. Adjust CTR for maximum DVM indication. See
Figure 3-34 for location of adjustment. If is at an
extreme of its adjustment range (fully meshed, maximum
capacitance, or unmeshed, minimum capacitance), increase or
decrease value of
and Refer to 3-3 for
range of values.
Note
is a fine adjustment, and is a coarse adjustment.
If is fully meshed, increase the value of or
Adjustments