HP 8562E, Service Manual

Page: 395 / 482

9. If the signal is not measured near the indicated power, troubleshoot the offset lock loop
buffer (function block AM of Al5 RF schematic sheet 3 of 4).
Table 11-6. Sampling Oscillator PLL Divide Numbers
sampling Center Reference Reference
Oscillator Frequency*
Divide Frequency
Frequency
(MHz)
Chain
Prescaler Postscaler
285.000
2156.3 10 2
15.000
286.364 2176.3 11
2 13.636
287.500 2199.5 8
3 12.500
288.462 2230.3
13 2
11.538
288.888 799.3 9
3 11.111
290.000 2263.3 10
3 10.000
290.909 2282.3 11
3 9.091
291.666 2302.3
9 4 8.333
292.500 2155.3 8
5 7.500
293.478
2158.3 23 2
6.522
294.444 2336.3
9 6
5.556
295.000 2196.3
10 6 5.000
296.000
1.3 15 5 4.000
296.471
2378.3 17 5
3.529
297.000
2410.3 20 5
3.000
297.222 2422.3 18
6 2.778
To set the sampling oscillator to a desired frequency, set span
to 0 Hz and to the value listed in the table.
10. Measure the 296 MHz loop feedback signal at the following test point:
11. If the feedback signal is not near the indicated power, measure the signals at the following
test points on the feedback path. Refer to function blocks AD, AG, and AH of Al5 RF
schematic.
12. Measure the 4 MHz loop-IF signal at the mixer output. The frequency of the IF is the
same as the reference frequency and can be found in Table 11-6.
(end nearest L414)
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Synthesizer Section