Re: Homodyne/Direct Conversion
G8HQP Dave has confused me! Until now, I had considered a homodyne to be a direct conversion receiver, with the locally generated carrier derived from the input itself with suitable limiting and filtering. so the frequency is always right. In other words, it's a special case of a synchrodyne (which does have a local, critically tuned oscillator, with PLL or some other sync system).
One thing which interests me - does a direct-conversion receiver work these days with Radio 4 on long wave? I ask this because the transmitter is now phase modulated with data to control electricity meters. It's transparent to a conventional envelope detector - but to a synchrodyne - ?
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