After FM62429 variable attenuator the audio signal is going to LM386 amp.The same signal is going to the MC3661 filter amp and detector. MC3361 is naturally the FM receiver IC and this receiver is using filter amp for detected signal AMP t…

c. 1st IF AMP, 2nd mixer, 2nd IF AMP, and detecter MC3661 is working as the 1st IF AMP and also the 2nd mixer combined with 10.245MHz crystal oscillator. The output of MC3661 is fed into LT455 ceramic filter prior to TA7640.TA7640 is worki…

The 1st local oscillator is MS5351 PLL managed by PIC18F1320. There is a rotary encoder to tune the frequency. We can select 100kHz or 10kHz step frequency by pushing the RE knob. The frequency is displayed on the front 7 segments 4 column…

The circuit of R80 front end section a. The front end filter and LNA The front stage filter is a stager style with two LC resonating circuits.L is D5x5 size, 4.5 turn（Estimated inductance is 68nH by WEB service "http://gate.ruru.ne.jp/rfd…

The block diagram of R80 receiver I'm wondering to buy R80 kit or not. I have been interested in various functions on R80. 1. They are saying that the LO is PLL. And I had come to know that the chip was MS5351 as was Si5351a clone.If so, t…