HP 3336A Operating Manual page 114

Model 3336A/B/C
Performance Tests
NOTE
When making harmonic distortion measurements with a spec-
trum analyzer, make sure that the analyzer's harmonic distor-
tion does not mask the distortion of the device under test. One
technique to ensure this is to increase the analyzer's input at-
tenuation, which results in lower signal levels at the analyzer's
input. This yields better intermodulation and harmonic distor-
tion performance. Adjust the analyzer's reference level controls
to obtain the proper display. For good harmonic distortion
performance in the -hp- Model 141T/8552B/8553B, the signal
level at its mixer must be less than — 40 dBm. If you are using
this analyzer, set its input attenuation to 40dB.
a. This test will require two different setups: one for frequencies equal to or less than 10
kHz and one for frequencies greater than 10 kHz.
b. Set the 3336 controls as follows:
OUTPUT sc iiuiaiern whack haw eeuss 75 ohm
AMPLITUDE es ocsneoriccet a 5.00 dBm
FAST LEVELING 2. cece ncseereieess OFF
c. Perform Steps d through f for each configuration listed below.
3336 FREQUENCY | FAST LEVELING SETUP
10 Hz OFF
30 Hz OFF
50 Hz OFF Figure 4-9A
10 kHz OFF
10 kHz ON
100 kHz OFF
100 kHz ON
1 MHz OFF
1 MHz ON Figure 4-9B
5 MHz OFF
5 MHz ON
20.9 MHz OFF
20.9 MHz ON
d. Tune the spectrum analyzer to display the fundamental frequency and at least four of
its harmonics.
e. Adjust the analyzer's input sensitivity controls until the amplitude of the fundamental
is 0 dB (full scale display).
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