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wrote:
wrote:

I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold. It works reasonably well when set it in the
sunshine and warms up. The problem seems to be the RF section since the
noise goes away when the volume is turned down. I'm suspecting the
germanium transistors may be the problem and wondering which one might
be replaced with a silicon variety to cure the temperature problems?

I'm not sure what all 8 transistors do. Two are in the output stage,
and another is used as a audio driver that drives the audio input
transformer.There are four RF coils, the usual oscillator (red) and
mixer (yellow) and white (1st IF) and (black (second IF). But that only
requires 6 transistors, and there are eight total. The detector is a
diode, so they didn't use a transistor for that. I haven't figured out
what the other 2 transistors do.

I'm thinking of replacing the oscillator transistor with a high gain
silicon variety to try and eliminate the temperature problems?

Any other ideas?

-Bill

Replacing parts at random on electronics makes not one bit of sense.
There are hundreds of components and hundreds of connections, any one
of which may be to do with it.

There are about about 50 components. This is little portable radio
about the size of 2 packs of cigarettes (5.25 by 3 by 1.25). I like it
because it's easy to carry around and sounds better than the smaller
versions.

Trying to repair a radio by replacing geraniums with silicon makes even less sense.
Germanium trs are still sold new as well as used.

If you dont know what youre doing, leave it alone.

Well, if I leave it alone, I can only use it on hot days. I'm trying to
figure out a way I can use it on hot and COLD days?

Maybe you have a suggestion to overcome the temperature problems?

-Bill