Dac Offset Voltage; Leveling Loop Amplifier Zero; Leveling Loop Bias; Output Amplifier Flatness - HP 3336A Operating Manual

Adjustments Model 3336A/B/C
These values are set by adjusting the dc offset and gain of the amplitude reference amplifier. a
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Required Equipment: \
ac voltmeter -hp- Model 3455A with Option 001
or -hp- Model 3490A
50 ohm feedthru termination -hp- Model 11048C
75 ohm feedthru termination -hp- Model 11094B
75 ohm cable ,
NOTE
The 3336 must be ON 30 minutes before attempting this adjust-
ment.
a. Connect the ac voltmeter to one of the unbalanced outputs, using the proper feedthru
termination at the voltmeter's input.
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b. Set the output amplitude to — 2.99 dBm using the 75 ohm output. Set the frequency
to 10 kHz.
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c. Adjust A4R259 until the ac voltmeter reads\.1941 Vrms, +.5 mV.
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d. Set the output amplitude to + 7.00 dBm.
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e. Adjust A4R261 until the ac voltmeter reads{.6130 Vrms, +1 mV.
g. Set the output amplitude to +3.00 dBm.
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h. The ac voltmeter should read .3868 Vrms, +1 mV. If this voltage is out of tolerance,
perform the following adjustments and ther try this adjustment again.
¢ Multiplier Input and Output Offset (5-17)
e —10.2 Vdc Reference Voltage (5-21)
® DAC Offset Voltage (5-23)
¢ Leveling Loop Amplifier Zero (5-25)
e Leveling Loop Bias (5-27)
5-31. Output Amplifier Flatness Adjustment.
5-32. This adjustment optimizes the ac feedback in the output amplifier, insuring the flattest
possible frequency response.
Required Equipment:
oscilloscope -hp- Model 1740A
50 ohm feedthru termination -hp- Model 11048C
75 ohm feedthru termination -hp- Model 11094B
5-10