HP 8566B Adjustment Manual page 323

set to internal leveling, which introduces minor leveling errors but
permits much faster sweep times.
40. Repeat steps 33 through 39 as necessary until the total
peak-to-peak deviation of the TRACE B waveform is less than
1.20 dB. Leave the TRACE B reference waveform in VIEW for
steps 33 through 36 to indicate which portions of the frequency
response waveform require relative adjustment.
change the
If necessary,
the adjustment ranges of A6AllR48 Al and A6AllR66 A2. A
decrease in the value of A6AlOR2 shifts
breakpoint higher in frequency, widening
Segment and narrowing the Band A Upper Segment. Conversely,
an increase in the value of A6AlOR2 shifts the Band A
frequency breakpoint lower in frequency. See Table 3-3 for the
acceptable range of values for A6AlOR2, and Table 3-4 for HP
part numbers. See Figure 3-90 for the location of A6AlOR2.
41. On the synthesized sweeper, key in Icw) 100 MHz, (jjj
LEVELING.
42. On the spectrum analyzer, key in [mj 8, MARKER
[ )
to position a marker on the peak of the displayed
PEAK SEARCH
100 MHz signal.
43. With the RF Section front-panel AMPTD CAL control still set to
the approximate center of its adjustment range, readjust 17-turn
potentiometer (Band A Step Gain) A6AlOR21 GA to adjust the
amplitude of the displayed 100 MHz marker to -10.00 dBm
fO.O1 dB. Adjust A6AlOR21 GA counterclockwise to increase the
signal level, and clockwise to decrease the signal level.
For A6AlO Miscellaneous Bias/Relay Driver Assembly, HP P/N
85660-60322 (HP 85660A/B RF Sections with serial number prefix
2747A or above):
If A6AlOR21 GA does not have sufficient range to adjust the
amplitude of the 100 MHz displayed signal to -10.00 dBm,
change the value of factory-select component A6AlOR86.
Increase the value of A6AlOR86 to decrease the signal level, and
decrease the value of A6AlOR86 to increase the signal level. See
Table 3-3 for the acceptable range of values for A6AlOR86, and
of A6AlOR86.
On the synthesized sweeper, key in m LEVELING, RF (OFF).
44.
Disconnect the power splitter from the spectrum analyzer RF
INPUT.
45. On the power meter, press
Disconnect the power meter rear panel RECORDER OUTPUT
from the synthesized sweeper front panel LEVELING EXT
INPUT.
2 1. Frequency Response Adjustments
value of factory-select component
the Band A frequency
the Band A Lower
]
(turning it off).
HOLD
Adjustments 3-l 83