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Ancient_Hacker

wrote:
I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold.

By "noisy" do you mean there is lots of background hiss, or do you mean
the sound is rough and distorted?

It works reasonably well when set it in the
sunshine and warms up.

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?

No. The radio was designed to work with germanium transistors. Every
stage you change over to silicon will need to be rebiased, retuned, and
reneutralized. Not an easy job.

I'd start with replacing the electrolytics. Quite likely they're at
about 20% of their original selves. Weak electrolytics can make the
radio motorboat, or sound tinny and noisy.