HP 3580A - Spurious Response Test

Model 3580A
PERFORMANCE TESTS
Section V
d. Reposition the following controls:
SWEEP MODE .................... SING
e. After waiting for the sweep to be completed
(100 sec.), verify that the noise on the display ± 10 Hz
(± 2 major divisions) away from the 10 KHz CAL signal (in
center of display) is at least 70 dB below the CAL signal.
5-34. Spurious Response Test.
a. Reposition the following controls:
INPUT SENSITIVITY ............. - 20 dB
FREQUENCY .................. 00.0 Hz
START-CTR ................... START
RESOLUTION BANDWIDTH ........ 30 Hz
FREQ. SPAN/DIV ................ 2 KHz
SWEEP TIME/DIV . . . . . . . . . . . . . . . 5 SEC
SWEEP MODE ................... RESET
b. Momentarily press:
DISPLAY ............... CLEAR WRITE
c. Adjust ZERO CAL for a peak display on the leftmost
display graticule.
d. Reposition the following controls:
SWEEP MODE ................. MANUAL
and momentarily press:
DISPLAY ............... CLEAR WRITE
e. Connect the frequency synthesizer (use proper out-
put impedance needed for the bandpass filter) to the input
of the bandpass filter. Adjust the filter for a 5 kHz center
frequency and adjust the synthesizer for a 5 kHz output.
(For a 50 ohm source and the White 2640 filter, connect a
550 n resistor (± 10%) in series between the filter and
synthesizer. This gives the 600 n source impedance re-
quired by the White filter (See Figure 5-3).
FREQUENCY SYNTHl;:SIZER
hp 33208
f. Connect the output of the filter to the input of the
3580A. Always terminate properly if required. (The White
Model 2640 filter requires no output termination. See
Figure 5-3).
g. Adjust MANUAL VERNIER for a display indication
at 5 kHz (2 1 /2 major divisions from left graticule). Adjust
the source level for a - 20 dBv (full scale) input to the
3580A (For the White 2640 filter and a 50 n source, this
corresponds to - 16.99 dBm 50 n level on the source).
Readjust MANUAL VERNIER for a peak display. Adjust
CAL 10 KHz for a full scale display.
h. Reposition the following controls:
SWEEP MODE .................... SING
i. After waiting for one complete sweep (50 sec.) verify
that all responses other than the zero response are at least
80 dB below the 5 kHz response.
5-35. Line Related Spurious Test.
Specification: > 80 dB below input reference level or
- 140 dBV (0.1 µV).
a. Disconnect the Synthesizer and Bandpass Filter from
the 3580A Input. Turn off all unnecessary equipment
located near the 3580A. This especially includes large
current users such as soldering irons, blowers, moters, etc.
b. Using a short piece of wire, connect a short across
the 3580A INPUT terminals.
c. Reposition the following controls:
INPUT SENSITIVITY . . . . . . . . . . . - 70 dB
RESOLUTION BANDWIDTH . . . . . . . . 3 Hz
FREQ. SPAN/DIV ................ 5 Hz
SWEEP MODE .................. MAN
MANUAL VERNIER. . . ......... centered
DISPLAY SMOOTHING ............ MAX
d. Connect the LO OUTPUT (rear panel) to the input
of an Electronic Counter (-hp- Model 5326A).
NOTE
If the power-line frequency is 50 Hz, substitute
the following Counter readings for Steps e and
f
SPECTRUM ANALYZER
hp 3580 A
Figure S-3. Spurious Response Test.
5-11