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Old 5th Dec 2017, 1:02 pm   #31
radioman
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Join Date: Apr 2003
Location: Ayr, Ayrshire, UK.
Posts: 631
Default Re: Two or three IF stage Chinese radio kits.

I didn't make any major changes. I did make R1=100k (as per the circuit diagram) and R14=220k. R14 damps the primary of the first IFT.
These changes are shown on my updated overlay picture.
You'll never get a hi-fi sound quality from this radio !
The speaker is very small and so is the output transformer, there is no negative feedback in the audio amplifier and I doubt if it outputs any audio frequencies below 300Hz. I didn't change any of the fixed-value capacitors and I don't think that changing any of them would make a difference.
I thought I might have to modify it before I actually built it but it's performance exceeded my expectations (which weren't that high).
It is what it is.
If you accept these limitations I'm sure you'll be quite happy with it.
Good luck with the build and don't forget to bridge the four pads on the PCB which I think are there for test purposes.

Andy
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