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Old 8th Nov 2018, 12:50 pm   #28
samoca58
Triode
 
Join Date: Sep 2014
Location: Ringwood, Hampshire, UK.
Posts: 29
Default Re: ZN414 and TA7642 radios

I have included some more pictures and a circuit as requested.
The first picture shows the mini TA7642 superhet board transplanted into a Perdio case. The new circuit uses the Perdio tuning cap, Ferrite aerial, wave change switch and volume on/off control. The other mini circuit is an LM386 audio amp. The Original OC45 IF circuitry on the left is isolated.
The next picture is the circuit.
The ceramic filter and IF transformers I purchased on eBay. A lot of 10 SFl455c devices can be obtained relatively cheaply.
The 3rd picture is my very first experiment using aerial, tuning cap and osc coil from an old Hong Kong radio.
Lastly is a picture using a similar dual gate mosfet version using Fab old Denco coils with varicap tuning !
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