Wavetek 3000 - Page 60

2 . Connect the equipment as shown in Figure 4-4 .
Oscilloscope
TEE
Figure 4-4 . AM Bandwidth Setup
3 . Set the modulation meter to read %AM at 50
MHz
.

Set
the
RF
input attenuation to 20 dB, the
IF
bandwidth to t400
kHz :, the meter response to fast, the function switch to +AM,
the meter range switch to 100 and the filter bandwidth to
75 kHz .
4 . Set the function generator for a 1 kHz sine wave output
and the attenuator controls for a 10 volt p-p sine waveon
the oscilloscope .
5 .
Adjust
the
Signal Generator MODULATION FM/AM control
for a
modulationmeter
reading
of -6
dB (approximately 50%
AM) .
6 . Maintain the 10 volt p-p output level and increase the
functiongenerator frequencyfrom 1 to 20 kHz . Observe the
modulationmeter scale .

It should read between -3 and -9
dB .

Note the change indB from the -6 dB calibration level .
7 . Repeat steps 4 through 6 with the modulationmeter fun-
ction switch set to -AM . Note the change in dB from the
-6 dB setting as in step 6 .
8 . Record the larger of the two dB changesobtained in
steps 6 and 7 on line 33 of the PTR .