5-7.
YO MAIN DRIVER, A55
Reference
Performance Test: None
Service Section: Sweep Generator
—
YO Loop
Description
The Main Coil Driver circuit gain and offset are adjusted for the correct output frequency.
DUT
50 flLOAD
A4 5 J 3
(OUTPUT OF
A45 DIRECTIONAL
COUPLER)
Figure 5-15.
VO Main Driver ASS Test Setup
Equipment
Frequency Counter
HP 5343A
50~) Termination, SMB(f)
HP P/N 1250-0676
Adapter, SMB (in) to SMB (in)
HP P/N 1250-0669
Procedure
1. Position the OUT in the test position as shown in Figure 5-15 with top and bottom covers removed.
Remove W3 (Figure 5-17) and connect the frequency counter to W51 as shown in Figure 5-15.
Allow
one-half hour for warm up time.
2.
Remove cable W38 from A49J2
and connect a 50 Ohm load to the end of the cable.
3. Set the OUT as follows:
a. Press [INSTRPRESET]
b. Press [CW]then enter [2]
[.]
[3] [GHz].
4. Adjust A55R47 (OFFSET, Figure 5-16) for an indication of 2.3 GHz ±1MHz on the Frequency
Counter.
5. Press the OUT’s [CW] key, then enter [6]
[.]
[9] [9] [9]
[GHz].
6. Adjust A55R4 (GAIN, Figure 5-16) for an indication of 6.999 GHz ±1MHz on the Frequency
Counter.
FREQUENCY COUNTER
HP 8340B/41B
Adjustments
5-39