HP 83522A Service Notes page 138

5-24. ALC GAIN ADJUSTMENT (UPDATES) (Cont'd)
1740A OSCILLOSCOPE
MODE
......................................................
MAIN
CHANNELAINPUT
............................................
AC
.............................................
CHANNEL A V/DIV
%V
............................................
CHANNEL B INPUT DC
..............................................
CHANNELBV/DIV 1V
........................................................
DISPLAY A
3. Adjust 1740A vertical and horizontal position knobs for waveform at the center of
oscilloscope CRT. Adjust START knob, below SWP button, for 10 kHz as displayed on
oscilloscope. Turn MODULATION RANGE Hz to 100 and VERNIER to 10K.
4. Connect equipment as shown in Figure 5-25.
5. On 1740A select A vs B MODE and set CHANNEL A to .OO5/DIV.
6. Adjust the far left side of the signal for 2 divisions pk-pk by using the CAL on the
CHANNEL A knob.
7. While monitoring CHANNEL A, manually sweep the entire plug-in frequency range and
adjust the ALC "GAIN (A4R15) for 4 divisions of peaking at the plug-in frequency where
the highest gain peaking occurs. (See Figure 5-26a)
4
D I V
ADJUST 'GAIN'
f
2 D I V REF
I
Figure 5-26a. ALC Gain Adjusted Correctly (Worst Case)
UPDATES
UPDATES APPLY TO ALL SERIALS