5. DC Log Amplifier Adjustments

5. DC Log Amplifier Adjustments

There are three DC Log adjustments; Limiter Phase, Linear Fidelity, and Log Fidelity. These adjustment need only be done under the following conditions:

Limiter

Phase

Only if a repair is made to blocks F, G, H, I, or J.

Linear

Fidelity

Only if a repair is made to blocks C, D, F, G, H, I, J, K, 0, IF Gain

 

 

Accuracy, RBW switching, or Log Fidelity.

Log Fidelity

Only if a

repair is made to blocks D, F, H, K, IF Gain Accuracy, RBW

 

 

switching,

or Log Fidelity.

If multiple adjustments are required they should be done in the following order:

1.Limiter Phase

2.Linear Fidelity

3.Log Fidelity

All adjustments should be made with all of the shields on and only after allowing at least a 20-minute warm up.

Assembly Adjusted

A4 Log Amplifier

Related Performance Tests

IF Gain Uncertainty Test

Scale Fidelity Test

Equipment

Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A

Adapters

Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1250-1476

Cables

BNC,122 cm(48in) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10503A Test Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...85680-60093

A4 Limiter Phase Adjustment

This adjustment consists of adjusting A4R445 for maximum on screen amplitude under the following conditions.

Adjustment Procedures 2-29