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Engineer
 
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"Gary" .uk wrote in
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"Engineer" wrote in message
...

My guess is that it is 1970's vintage, perhaps a bit before.


Circa '74

It has 9
transistors (2 power types); no integrated circuits; cannot find

any
IFT's (very odd!) but there are a total of 7 unshielded coils on

the
PCB. It has a 2 gang tuning capacitor with one gang of lower
capacitance than the other with 10 plates vs. 11, about 390/500 pF

in
size - suggests an oscillator to me, i.e. not a TRF set.


It was a simple superhet. I think the IFT's may've been little

ceramic
types? It's *so* long ago...
Front end was a 40673 MOSFET. The audio quality of the rx was very

nice, but
of course meant selectivity was poor. Also the AGC was pathetic, it
overloaded very easily. The audio stage was prone to microphony, a

damping
cicruit across the speaker helps.

HTH
Gary

Many thanks, Gary. I'll see what I can do with it.

Cheers,

Roger