> (like a crystal on 3.560.0MHz > mixed with an oncoming signal on 3.560.6MHz would give the sum and the > difference of +/-600Hz, then you filter one out and just receive the > other). > Sorry, my keyboard is playing up and missing the 'k' out! That should be 600kHz. Plus, the difference between the crystal and radio frequencies needs to produce an output in the audio frequencies, of course...
Dave (G0DJA)
