Alinco DJ-596E, Руководство по обслуживанию

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5
UHF
IC2 compares the frequency gained by dividing the signal added to pin 19 of
IC2 by the control signal from IC6 with the frequency gained by dividing the
reference frequency of 12.9 MHz inside IC2. When the phase difference is
found as a result of phase comparison, the pulse signal is output from the
charge pump output of pin 13 of IC2, then the signal is converted into the DC
voltage at the inside circuit for passive filter and added to the cathode side of
VCO vari-cap D16 and D18 to make the phases equal. In result the stabilized
oscillation can be done at the desired frequency.
2) [TX]
1. Microphone Amplifier
The microphone amplifier IC14 has 2 operational amplifiers. The voice is
converted into the electric signal through the microphone, then supplied to
IC14. The input signal is amplified and pre-emphasized to be output.
VHF
The signal output from microphone amplifier is adjusted the maximum
frequency deviation in WFM mode at VR1, then adjusted the maximum
frequency deviation in NFM mode at VR2. The adjusted signal is added to the
cathode of VCO vari-cap D11 for deviation to change the capacity of the
oscillation circuit resulting the FM deviation.
UHF
The signal output from microphone amplifier is adjusted the maximum
frequency deviation in WFM mode at VR3, then adjusted the maximum
frequency deviation in NFM mode at VR4. Then the adjusted signal is
added to the cathode of VCO vari-cap D17 for deviation to change the
capacity of the oscillation circuit resulting the FM deviation.
2. Power Amplifier
The oscillated signal at VCO is supplied to the power amplifier Q5, passing
through buffer amplifier Q7, driver amplifier IC1 and Q6. The power-amplified
signal is supplied to the antenna through the duplexer after the harmonics are
attenuated enough.