80 Chapter 2
Performance Verification Tests
10. Residual FM
delta (∆ Mkr1) amplitude reads −8dB ±0.3 dB.
7. Press Delta, then rotate the knob counterclockwise until the marker
delta (∆ Mkr1) reads −4dB ±0.3 dB.
If you have difficulty achieving the ±0.3 dB setting, then make the
following analyzer settings:
Sweep, Sweep (Cont)
SPAN, 2kHz
BW/Avg, Video BW, 30 Hz (Man)
Repeat step 5 through step 7.
8. Divide the marker delta (∆ Mkr1) frequency in Hertz by the marker
delta (∆ Mkr1) amplitude in dB to obtain the slope of the resolution
bandwidth filter. For example, if the marker delta (∆ Mkr1) frequency
is 275 Hz and the marker delta (∆ Mkr1) amplitude is 3.92 dB, the
slope would be equal to 70.15 Hz/dB. Record the result below:
Slope ____________ Hz/ dB
Measuring the Residual FM
9. On the analyzer, press:
Marker, Off
Peak Search (or Search)
Meas Tools
Delta
10.Rotate the knob counterclockwise until the marker delta (∆ Mkr1)
amplitude reads −10 dB ±0.3 dB.
11.On the analyzer, press the following keys:
Marker, Normal
Marker →, Mkr → CF
Single
BW/Avg, Video BW (Man), 1kHz
SPAN, Zero Span
Sweep, Sweep Time
100 ms, Single
The displayed trace should be about five divisions below the
reference level. If it is not, press Sweep, Sweep (Cont), FREQUENCY,
and use the knob to place the displayed trace about five divisions
below the reference level. Press Single.
12.On the analyzer, press Peak Search (or Search),
Pk-Pk Search. Read the marker delta (∆ Mkr1) amplitude, take its
absolute value, and record the result as the Deviation.
Deviation ____________ dB
13.Calculate the Residual FM by multiplying the Slope recorded in