Kirisun FM540, Service Manual

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FM540 Service Manual
6.1.3. Modulation by Computer
TX
1.TX frequency
On the computer mode [frequency stability], the transmitting frequency is adjusted within ±100Hz.
2.Power
a.On the computer mode [TX high power], adjust the TX high power as 25W±2W.
b.On the computer mode [TX middle power], adjust the power middle power as 10W±2W.
c.On the computer mode [TX low power],adjust the TX low power as 5W±1W.
3. Maximum Frequency Deviation (modulation signal is1kHz/120mV)
On the computer mode [maximum audio frequency deviation], adjust TX maximum frequency deviation
and adjust the deviation as 1.8-2.5kHz.
4. DCS Balance
On the computer mode [DCS balance], adjust DCS balance to make the demodulated DCS wave flat and
square.
5. DCS Frequency Deviation (DCS: 023N)
On the computer mode[DCS frequency deviation],adjustDCS as 0.3-0.5kHz.
6. CTCSS Frequency Deviation (CTCSS: 67.0Hz, 150.4Hz, 250.4Hz)
On the computer mode [CTCSS(67Hz, 150.4Hz, 250.4Hz) frequency deviation], adjust CTCSS
frequency deviation as 0.3-0.5kHz
DŽ
7. DTMF Frequency Deviation
On the computer mode[DTMF frequency deviation], adjust DTMF frequency deviation as 1.5-2kHz.
8. Battery low voltage indication when transmitting
Set the voltage as 6.8V and on the computer mode [transmitting low voltage], click OK when digital is
stabilized.
RX
1. RX Pass Band
a.Program the spectrum analyzer and use a high frequency probe to test the RX pass band at the test
point.
b. On the computer mode [RX sensitivity] ,adjust the RX pass band to the proper center frequency.
2. Maximum Volume
Set the RF frequency as the center frequency, signal strength as 1mV and modulated frequency
deviation as 1.5kHz. On the computer mode, adjust the computer to make the audio power as 1.1-1.3W.
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