Sgt. Schultz wrote:

How do you build a foxhole radio? I saw a few plans on the internet,
but I don't understand them. I have read that you can use a telephone
receiver instead of crystal earphones. Is this true? Also, is it
possible to make a version without the razor blade? Sorry if I sound
stupid here. I am not an expert with radio. Thanks in advance.

The intent of a "foxhole" radio was a real-world example of how to build
a functional receiver under the worst of conditions and limitations.
That implies using components that will "get by" in a pinch.

Basically you're referring to a plain old crystal detector set. Yes, a
1N34A diode will work much better than a razor blade and hi-z phones
will work better than a telephone headset. But they didn't have hi-z
phones and 1N34A diodes available in the foxholes and prison camps of
WW2 and thats the legacy of the "foxhole radio".

Building one is an interesting exercise and may provide some learning
experience as well as a baseline comparison for *any* other type of
radio receiver. The more interesting part of such a radio is your
imagination if you can imagine yourself under the same conditions
totally isolated from the outside world of news and how important such a
thing could be.

The downside is that the old-timey razor blades are no more. Read up on
the techniques to modify newer blades...heat, corrosion, etc.

GL,
Bill