Receiver system

The receive signal from the ANT terminal passes through the final unit and the TX-RX unit LPF and is applied directly to mixers Q9 and Q10 (2SK125-5). Here the signal is mixed with the first local oscillator frequency (71.395-101.295 MHz) from the PLL in order to generate the first IF signal of 71.295 MHz. The receive frequency may be fine tuned with the clarifier by varying the first local oscillator frequency.

The 71.295 MHz first IF signal passes through a monolithic filter (MCF) and is mixed with the second local oscillator frequency (60.6 MHz) by MIX FETs Q13 and Q14 (2SK520(K44)) to generate a 10.695 MHz second IF signal. The second local oscillator signal is generated by the TX-RX unit Q90 and Q91 (2SC2714(Y)) and is then doubled by Q56 (2SC2714(Y)).

The second IF signal (10.695 MHz) passes through a crystal filter, and is then applied to IC2 : KCD03 where the signal is demodulated. The demodulated audio output is amplified by the AF preamplifier and power amplifier to drive the speaker.

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