ALAN Electronics Tectalk FM PMR 446, Service Manual

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4.3 TRANSMITTER TEST
a) Output Power Test
Power(6.0V DC) should be Max.500mW and in +/- 20% range.
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- 3kHz. Check the audio level for 300Hz - 3kHz based on
frequency standard, 1kHz.
c) Modulation Degree Test
1) Connect AF oscillator to the MIC terminal and then adjust the
level to 60mV
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
+/- 2.5KHz.
d) Spectrum Test
1) Antenna is 50 Ohms (internally) and attenuator degree should be 20dB
more.
2) Observe the spectrum with pressing PTT key.
The harmonics should be less -36/-30dBm than carrier.
4 RECEIVER
a) Preparation
1) Adjust the power supply to DC 6.0V
2) Adjust Voltage level to 0.7Vrms(8 Ohms load) after power on.
b) Connection method
c) Setting of Rx sensitivity
1) Adjust SSG to channel frequency.
2) Adjust modulation frequency, 1kHz to modulation degree, 1.5KHz.
4) After adjusting the frequency of SSG to channel frequency, RF
level sets to -47dBm.
S S G E U T 8 OHMS LOAD
POWER SUPPLY
AV VTVM
OSCILLOSCOPE
DISTORTION METER
SINAD METER