The AP-80 An Alternative Pixie
The Pixie is about the simplest rig ever devised, using just 2 transistors and a LM386 audio amp. The circuit starts with a standard Collpits crystal oscillator. In order to provide a 600 Hz frequency shift, a trimmer cap and 2N7000 FET is added in series with the crystal. During transmit, the 2N7000 is turned on, effectively shorting out the trimmer cap and lowering the oscillator frequency.
   The AP-80 An Alternative Pixie
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