b) Audio Response
Connect AF oscillator to Mic terminal and then firm the audio level
that doesn't distortion the wave of oscilloscope in the frequency range,
300Hz to 3kHz. Check the audio level for 300Hz to 3kHz based on frequency
standard, 1kHz.
c) Modulation Degree Test
1) Connect AF oscillator to the MIC terminal and then adjust the level
to 100mV
2) Measure the oscilloscope wave and he point needle of modulation meter
after pressing PTT key.
3) Sweep gradually the frequency of AF oscilloscope from 300Hz to 3kHz.
4) At this time, the point needle of modulation meter should be in
the limit of +/- 2.5 kHz.
d) Spectrum Test
1) terminate antenna output with 50 Ohms and use a power attenuator of 20 dB, to avoid
harmonics generated by analyzer overload.be 20dB more.
2) observe the spectrum with pressing PTT key. The harmonics should be
less than -36/-30 dBm (with 20 dB external attenuator the reading will be –56/-30 dBm).
4.4 RECEIVER
a) Preparation
1) Adjust the power supply to DC 6.0V
2) Adjust Voltage level to 0.7Vrms( at 8 Ohms speaker output load) after power on.
b) Connection method
SSG
EUT
DISTORTION METER
AV VTVM
OSCILLOSCOPE
8 Ohms LOAD
POWER SUPPLY
SINAD METER
