Alinco DJ-V57, Service Manual

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result of phase comparison, the pulse signal is output from the charge pump
output of pin 21 of IC102, then the signal is converted into the DC voltage at
the low pass filter and added to the cathode side of VCO vari-cap to make the
phases equal. In result the stabilized oscillation can be done at the desired
frequency.
[Transmission]
1. Microphone Amplifier
The microphone amplifier IC110 has four operational amplifiers. The voice is
converted into the electric signal through the microphone, and then supplied to
IC110. The input signal is amplified and pre-emphasized to be output.
The signal output from microphone amplifier is adjusted the maximum
frequency deviation at D/A converter IC106. The adjusted signal is added to
the cathode of D111 of VHF or D123 of UHF VCO for deviation to change the
capacity of the oscillation circuit resulting the FM deviation.
2. Power Amplifier
The oscillated signal at VCO is amplified at pre-driver amplifier IC101, driver
amplifier Q105 and power amplifier Q101. The power-amplified signal is
supplied to the antenna through the duplexer after the harmonics are rejected
enough at the low pass filter.