Variable Attenuation Measurement (10 MHz to 26.5 GHz)

TB 9-4931-523-24

NOTE

Verify the proper Cal Factors are loaded for the power sensor

module being utilized.

NOTE

Ensure measuring receiver measurement accuracy is set to high.

(1) Adjust signal generator frequency controls to the first test frequency recorded in

7 a above and adjust output for 0.0 dBm.

(2) Configure measuring receiver for tuned RF level measurements and manually

enter carrier frequency into measuring receiver. Record reading as reference.

(3) Adjust signal generator output in 10 dBm steps to -70 dBm.

Allow the

measuring receiver to acquire the signal at each level.

NOTE

Use adapters as needed.

NOTE

Use 50 Ω to 75 Ω or 50 Ω to 93 Ω adapters when TI is 75 Ω or 93 Ω.

(4) Adjust signal generator output for 0.0 dBm indication on measuring receiver.

(5) Configure measuring receiver in the ratio mode.

(6) Connect the attenuator at the TI INSERTION POINT as shown in figure 1.

(7) Measure and record measuring receiver indication. Measured attenuation will

be within range and accuracies specified in appendix A for TI being calibrated.

NOTE

When calibrating a set of attenuators test each attenuator in

the set at each test frequency before setting a new

reference frequency.

(8) Repeat steps (1) through (7) above for remaining test frequencies recorded in

7 a above.

b. Adjustments. No adjustments can be made; however, a correction chart may be

prepared listing actual measuring receiver indications at frequencies of interest.

9. Variable Attenuation Measurement (10 MHz to 26.5 GHz)

a. Performance Check

NOTE

The frequency range of the TI will determine which sensor

module is used. 504: 100 kHz 4.2 GHz, 518: 10 MHz 18 GHz,

526: 30 MHz 26.5 GHz.

NOTE

Verify the proper Cal Factors are loaded into the controller for

the power sensor module being utilized.