HP 8566B Adjustment Manual page 345

LOG SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 dB/DIV
187. Press MARKER (-1 and adjust (IF Step Gain) potentiometer
If A6AlO Miscellaneous Bias/Relay Driver Assembly is HP P/N
85660-60322 (HP 85660AB RF Sections with serial number prefix
2747A or above), and A6AlOR81 GF does not have sufficient range,
change the value of factory-select component A6AlOR91. Increase
the value of A6AlOR91 to decrease the signal level, and decrease the
value of A6AlOR91 to increase the signal level. See Table 3-3 for the
acceptable range of values for A6AlOR91, and 'Ihble 3-4 for HP part
numbers. See Figure 3-90 for the location of A6AlOR91.
188. Disconnect the low-loss microwave test cable from the spectrum
analyzer front panel 321.4 MHz IF INPUT connector. Reconnect
the jumper cable between the spectrum analyzer front panel
32 1.4 MHz IF INPUT and IF OUTPUT connectors.
189. On the spectrum analyzer, key in m Q) u, 6 Hz, m
( )
REFERENCE LEVEL
190. In the RF Section, disconnect cable 84 (gray/yellow) from
the cover to the A6 RF Module, and then reconnect cable 84
(gray/yellow) to A6A12Jl and cable 82 (gray/red) to A6A12J2.
191. Remove the jumper between A12TP2 and A12TP3 (LOCK
INDICATOR DISABLE) on the Al2 Front Panel Interface
Assembly in the RF Section.
192. Replace the RF Section bottom cover.
2 1. Frequency Response Adjustments
Adjustments 3-205