Peter Onion wrote:
> I think any simple circuit like that is going to be problematical as it
> has nothing in it to cope with the variations in amplitude of the
> signal , afterall it is Amplitude Modulated !

Hm. The signal is fed into a 4007 inverter that's been biased into its linear 
region. Then the signal is amplified again in the same way and fed into one 
final stage of the 4007 which is wired as a normal inverter.

There should be plenty of amplification there to pick out the carrier and 
ignore the amplitude modulation. With 500mV out of the receiver (which is the 
case for most of the UK) it'll clip nearly all the time...

I might try getting rid of the amp stage and cap-coupling the 500mV RF 
straight into the input of the 4046...

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