5-14.
UNLEVELED RF OUTPUT ADJUSTMENTS (Cont’d)
74. Using the [a]
key on both the OUT and the LO, step through Band 2, observing the Spectrum
Analyzer display at each step. There may be responses due to mixing products. These will appear
as low level signals. A squegging response will appear as a higher amplitude signal as shown in
Figure 5-44. If squegging occurs at OUT frequencies below 10 GHz, adjust A24R3 (X2A) slightly
CCW to eliminate squegging. If squegging occurs at frequencies above 10 GHz, adjust A24R4
(X2B) to eliminate the squegging. Note, if the control is adjusted and there is no effect on the
response, the response is probably a mixing product.
75. For Band 3, press the Local Oscillator [STARTFREQ] and enter [1] [2]
[.]
[9] [GHz].Press [STOP
FREQ] and enter [1] [9]
[.]
[4] [GHz]. Press [MANUAL] and enter [1] [2]
[.]
[9] [GHz].
76. On the OUT press [POWERLEVEL] and enter [2] [0] (dBm]. Press [STARTFREQ] and enter
[1] [3]
[.]
[5] [GHz]. Press [STOPFREQ] and enter [2] [0] [GHz]. Press (MANUAL] and enter
[1] [3]
[.]
[5] [GHz].
77. Using the step keys as described in step 26, step through Band 3. If squegging occurs below 15
GHz, adjust A24R6
(X3A) slightly CCW to eliminate the squegging. If squegging occurs above 15
GHz, adjust A24R7 (X3B).
Band 4 Adjustments, HP 8340B only
78. For Band
4, press the Local Oscillator [STARTFREQ] and enter [1] [9]
I.]
[4] [GHz]. Press
[STOPFREQ] and enter [2] [5]
[.]
[9]. Press [MANUAL]and enter [1] [9]
[.]
[4]
[GHz].
79. On the OUT press [STARTFREQ] and enter [2] [0] [GHz]. Press [STOP FREQ] and enter
[2] [6]
[.1
[5] [GHz].Press [POWERLEVEL] and enter [2] [0] [dBm]Press (MANUAL] and enter
[2] [0] [GHz].
80. Using the step keys as described in step 26, step through Band 4. If squegging occurs below
23 GHz, adjust A24R9 (X4A) slightly CCW to eliminate the squegging. If squegging occurs above
23 GHz, adjust A24R10 (X4B).
NOTE
If adjustments of the calibration constants were made in this procedure,
the data thus stored in the “working memory area” should be copied to
the “protected memory area” by pressing the following key sequence:
[SHIFT][1] [4] [Hz] [SHIFT][kHz] [5] [3] [4] [9] [Hz] [INSTRPRESET].
5-88
Adjustments
HP 8340B/41B