Input Probe Compensation - HP 3580A Operating And Service Manual

Section III
BASIC OPERATING PROCEDURES
Model 3580A
b. Set the 3580A controls as follows:
DISPLAY ..... STORE and BLANK S'fORE
Released
AMPLITUDE MODE ....... LOG 10 dB/DIV
AMPLITUDE REF LEVEL ....... NORMAL
dBv /LIN - dBm Switch ........... dBv /LIN
INPUT SENSITIVITY ............... CAL
VERNIER ....................... CAL
(Fully CW)
FREQUENCY . . . . . . . . . . . . . . . . 10.0 kHz
START CTR ...................... CTR
BANDWIDTH . . . . . . . . . . . . . . 1 Hz or 3 Hz
(whichever is to be used)
DISPLAY SMOOTHING ............. MIN
FREQ. SPAN/DIV .................. 0 Hz
SWEEP TIME/DIV .................
NJ
A
SWEEP MODE .................... MAN
c. Turn the ADAPTIVE SWEEP control to the on
position so the sweep marker (gap) appears on the
horizontal trace. Leave the baseline threshold at the bottom
of the screen.
d. While pressing the CLEAR WRITE button, adjust the
MANUAL VERNIER so that the sweep marker is in the
center of the display. Release the CLEAR WRITE button
and set the ADAPTIVE SWEEP control to the OFF
position.
e. Pull out on the FREQUENCY control for fine
tuning. Carefully adjust the FREQUENCY control for a
peak 10 kHz response in the center of the display.
f. Using a small screwdriver, adjust the front panel CAL
10 KHz potentiometer so that the peak of the 10 kHz
response is exactly full scale.
g. Set the AMPLITUDE MODE to LOG 1 dB/DIV.
Repeat Step f.
3-202. For operation on the 10
Hz,
30 Hz, 100
Hz
or
300 Hz BANDWIDTH proceed as follows:
a. Turn the instrument on (Paragraph 3-192) and
perform the Frequency Calibration Procedure (Paragraph
3-195).
b. Set the 3580A controls as follows:
3-28
DISPLAY ..... STORE and BLANK STORE
Released
AMPLITUDE MODE ....... LOG 10 dB/DIV
AMPLITUDE REF LEVEL ....... NORMAL
dBv /LIN - dBm Switch ........... dBv /LIN
INPUT SENSITIVITY ............... CAL
VERNIER ...................... CAL
(Fully CW)
FREQUENCY . . . . . . . . . . . . . . . . 10.0 kHz
START CTR ...................... CTR
BANDWIDTH . . . . . . . . . . . . 10 Hz-300 Hz
(whichever is to be used)
DISPLAY SMOOTHING ............. MIN
FREQ. SPAN/DIV ........... See Table 3-6
SWEEP TIME/DIV .......... See Table 3-6
SWEEP MODE ..................... REP
c. Using the ADAPTIVE SWEEP control, set the base-
line threshold to - 60 dB on the display.
d. Using a small screwdriver, adjust the front panel CAL
10 KHz potentiometer so that the peak of the 10 kHz
response is exactly full scale.
e. Set the AMPLITUDE' MODE to LOG 1 dB/DIV.
Using the ADAPTIVE SWEEP control, set the baseline
threshold to the bottom of the display. Repeat Step d.
Table 3-6. Control Settings.
(Amplitude Calibration)
BANDWIDTH
FREQ
SWEEP
SETTING
SPAN/DIV TIME/DIV
10 Hz
20
Hz 0.5 SEC
30 Hz 0.1 kHz 0.2 SEC
100 Hz 0.5 kHz 0.1 SEC
300 Hz 1 kHz 0.02 SEC
3-203. Input Probe Compensation.
3-204. Before using a 10:1 voltage divider probe it is
necessary to adjust the probe for optimum frequency
response. Once the probe is properly adjusted, it should not
require further attention. It is good practice, however, to
perform periodic verification tests to ensure that optimum
adjustment is maintained.
a .. Turn the instrument on as outlined in Paragraph
3-192.
b. Connect the probe to the 3580A INPUT using a BNC
to bahanna-plug adapter (-hp- Part No. 1251-2277).
c.. Set the 3580A controls as follows:
ADAPTIVE SWEEP ................. -OFF
DISPLAY ..... STORE and BLANK STORE
Released
AMPLITUDE MODE ....... LOG 10 dB/DIV
AMPLITUDE REF LEVEL ....... NORMAL
INPUT SENSITIVITY ............. - 10 dB
FREQUENCY ................. 00.0 kHz
START CTR .................... START
BANDWIDTH . . . . . . . . . . . . . . . . . . 300 Hz
DISPLAY SMOOTHING ............. MIN
FREQ. SPAN/DIV ................ 2 KHz
SWEEP TIME/DIV ............. 0.05 SEC
SWEEP MODE ..................... REP
d. Set the rear panel LEVEL control fully clockwise (fac-
ing rear panel).