[Sideband]

Product detectors are mainly found in Communications receivers. They are particularly useful when listening to SSB transmissions. Very simply, they are a mixer type demodulator where one input is fed directly with the I.F signal and the second input from the BFO (or the carrier insertion oscillator). The valve (or transistor) then mixes the two inputs to provide an AF output. It won't reproduce AM because, as the name implies, it requires two inputs to provide the output. The circuit is quite simple and just requires a small amount of RF filtering on the output.

This is a very simplistic description and no doubt someone else can give a more detailed description if necessary.


SB