![HP 3585A Скачать руководство пользователя страница 177](http://html.mh-extra.com/html/hp/3585a/3585a_service-manual_161430177.webp)
Adjustments
Model 3585A
5-64
d. Adjust the Range Down Threshold, AIRI74, so that the voltmeter reading just goes to
a low logic level « 0. 5V).
e. Remove the voltmeter.
5·39. Top Of Screen Amplitude Adjustment
a. Set the synthesizer controls for:
FREQUENCY . . . . . . . . . . . . . . . . . . . . . . " . . . . . 1 50kHz
AMPLITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . -25dBm
b . Set the 3585A controls for:
RECALL 601
INSTRUMENT PRESET
CENTER FREQUENCy . . . . . . . . . . . . . . . . . . . 1 50kHz
RANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -25dBm
AUTO RANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . off
RES BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30kHz
dB/DIV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . IdB
MANUAL SWEEP . . . . . . . . . . . . . . . . . . , . . . . . . . . . . on
c. Adjust A17R105 for a marker amplitude reading of .. 25 .0OdBm.
d. Enter SAVE 1 on the 3585A.
5·40. Calibrator Level Adjustment
NOTE
It is important that the amplitude accuracy of the source used for
this adjustment is excellent. The amplitude accuracy of the 3585A
depends on the amplitude accuracy of this source.
a. Set the 3585A control for:
INSTRUMENT PRESET
RECALL 1 (same settings as in top of Screen
Amplitude Adjustments)
b. Adjust AIR39 so that the marker amplitude reads exactly -25 .00dBm. The results of
this adjustment can only be analyzed after performing th€! next two steps.
c. Enter RECALL 4 on the 3585A keyboard.
d. View the results of your adjustment. Repeat the two previous steps until a marker
reading of exactly -25 .00dBm is obtained after a calibration (RECALL 4).