10. Residual FM, HP 8591EM

Measuring the Residual FM

6. On the EMC analyzer, press the following keys:

4SWEEP/TRIG5 SWEEP CONT SGL (CONT)

4MKR5 MARKER 1 ON OFF (OFF)

4SPAN5 ZERO SPAN

4SWEEP/TRIG5 SWP TIME AUTO MAN (MAN) 300 4ms5

4FREQUENCY5

7.Rotate the EMC analyzer knob until the displayed trace is approximately 3 divisions below the reference level, then press 4SGL SWEEP5.

8.On the EMC analyzer, press 4MKR !5, More 1 of 3 , MARKER !PK-PK . Read the MKR-1 amplitude, take its absolute value, and record the result as the Deviation.

Deviation dB

9.Calculate the Residual FM by multiplying the Slope recorded in step 5 by the Deviation recorded in step 8.

Record this value as TR Entry 2 of the performance veri￿cation test record. The residual FM should be less than 30 Hz.

The \Residual FM" performance test is now complete.

2-50 Performance Veri￿cation Tests