16. Second IF Gain Adjustment

Assembly Adjusted

Al5 RF Assembly

Related Performance Test

IF Input Amplitude Accuracy

Description

The gain of the Second IF (between A15J801 INT Second IF and the third mixer) is set to

12dB.

Note

This adjustment is necessary after replacing either A15Al Second IF Amplifier

 

or A15U802 Second IF pad.

 

 

Equipment

No test equipment or test setup is required for this adjustment procedure.

Procedure

1.Set the HP 8560A m switch off, disconnect the power cord, and remove the analyzer cover. Fold down the Al5 RF and Al4 Frequency Control assemblies. Prop up the Al4 Frequency Control assembly.

2.Remove the shield covering the third converter and A15Al Second IF Amplifier. See Figure 2- 19.

3.Read the gain printed on the A15Al Second IF Amplifier label. Select a value for A15U802 from Table 2-13 based upon the gain of the Second IF Amplifier.

4.Reinstall the shield on the Al5 assembly.

5.Perform the External Mixer Amplitude Adjustment.

Note

If the second IF input switch is repaired, there might be insufficient range in

 

the External Mixer Amplitude Adjustment. If this is the case, select a new

 

value for A15U802. Greater attenuation values of U802 will lower the signal

 

amplitude, and lower attenuation values will increase the signal amplitude.

 

 

2-60 Adjustment Procedures