
The receiver takes the form of a simplified Tayloe detector. An RF preamp circuit amplifies the signal from a shortwave antenna and feeds it into a 74HC4066D analog switch, which acts as a switching mixer. It mixes the input signal with the local oscillator’s I and Q signals to produce the intermediate frequency signals. The local oscillator consists of a SI5351 clock generator with a 74HC74D flip-flop to generate the I and Q pair. The signals pass through a low pass filter stage and get amplified by an LM358 op amp, resulting in the IQ signal pair being fed to a computer’s stereo sound card.
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