HP 85640A, Operating And Service Manual

Page: 126 / 169

4. Tracking Oscillator Range A djustments
4. Tracking Oscillator Range A djustments
Assemblies A djusted
A2 tracking generator assembly
A3 interface assembly
Related P erformance T est
Tracking adjustment range
Description
The centering of the tracking oscillator range is adjusted in the factory to ensure that the
tracking adjustment works properly . Over a period of 5 years , however , the center frequency
of the tracking oscillator range may drift outside of acceptable limits . These limits are tested
with the tracking adjustment range performance test in Chapter 4 of this manual. P erform this
adjustment only if the tracking adjustment range performance test has failed.
This adjustment centers the tracking oscillator range . Typically , performing the ne adjustment
on the A3 interface assembly is sucient. In some cases , however , adjusting the A2 tracking
generator coarse adjustment is necessary . The coarse adjustment, A2C3, is rated for a
maximum of 10 adjustment cycles . Because of this limitation, adjust A2C3 only when
absolutely necessary .
Caution
The tracking generator assemblies are static-sensitive . P erform this adjustment
procedure at a static-safe workstation. Refer to Figure 7-1 for an example of a
static-safe workstation.
Figure 5-7. Tracking Oscillator Range A djustment
HP 85640A RF T racking Generator Operation and Service Manual Adjustment Procedures 5-15