16.Second IF Amplifier and Third Converter Adjustment

Reference

Description

RF Section:

A19 Second IF AmplifierA20 Third Converter

A synthesized sweeper is used to inject a signal of 301.4 MHz at -20 dBm in to the A19 Second IF Amplifier. The output of the amplifier is displayed on a scalar network analyzer. The amplifier is adjusted for a bandpass of greater than 7 MHz and less than 14 MHz centered at

301.4MHz. Its gain should be greater than 14 dB and less than 17 dB. A spectrum analyzer is used to view the output of the 280 MHz Oscillator on the A20 Third Converter and the oscillator is centered in its adjustment range.

SPECTRLM ANALYZE

SYNTHESIZED WEEPER

 

PCYhER

METER

 

 

 

2 0 dB

 

SPECTRUM ANALYZER

ATTENUATOR

 

(Dovisa U n d e r Tut)

 

 

 

 

NETWORK ANALYZER

Figure 3-63. Second IF Amplifier Adjustments Setup

Equipment Spectrum Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . HP 8566A/B Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A/B Scalar Network analyzer . . . . . . . . . . . . . . . . . . . . . . . HP 8757A Power Splitter . . . . . . . . . . . . . . . . . . . . . . HP 11667A Opt. 001 PowerMeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A Detector (2 required) . . . . . . . . . . . . . . . . . . . . . . . . . HP 11664A 20 dB Attenuator . . . . . . . . . . . . . . . . . . . . HP 8491A, Opt. 020

3-112 Adjustments