[CW] OT: foxhole radios

[Jude DaShiell]

Now I'm thinking to build a good set these Africans had best buy parts in
America before returning home.



Jude <jdashiel at panix dot com> "There are four boxes to be used in
defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)

.

On Mon, 24 Oct 2022, Joseph L. Pontek Sr. wrote:

> The fox hole radio was a very basic crystal radio. My first radio
> was a crystal radio. It had a crystal in a glob of lead (solder) and
> what they called, a cats whisker. It was a spring loaded wire that
> you could move around on the crystal until you found a "hot spot."
> When I talked to my Uncle Stan, a WW II vet, he told me about
> using the razor blades. I think in a Boys Life magazine, I read
> about that method. Both were very finicky to get to work. Then
> my Great Uncle Vern gave me a little diode, maybe a 1N34A
> or the like. Worked right off!
>
> The diode does not generate electricity, it simply rectifies RF
> that is picked up via a wire (antenna) and against a ground.
> I made tuning coils by wrapping enamel insulated wire on
> paper tubes, toilet paper tubes, oat meal boxes, etc. I sanded
> the insulation with sand paper and made a sliding contact
> the shorted out part of the coil, ie, tuned it. It was very broad
> banded, so I heard two local A.M. broadcast stations at the same
> time. I used a pair of surplus crystal earphones.
>
> If you want to supply some one the needed materials, I would
> assemble some diodes, like 1N34A, 1N914, or such, enameled
> copper wire for the coil, earphones, hook up wire and, maybe,
> fan-stock clips, some hardware, like screws and nuts and some
> antenna wire.
>
> My first ones were made on just a piece of wood. They got me into
> electronics, ham radio and career in electronics 70+ years ago.
>
> I used to teach ham radio classes at the Michigan School for the
> Blind, so I understand the handicap fairly well.
>
> I hope this helps.
>
> 73, Joe, K8JP/K5
>
>
> On 10/24/2022 8:05 AM, Jude DaShiell wrote:
> > Hi David,
> > That's all the information I got on foxhole radios some of them used
> > graphite pencils and razor blades.  Two different kinds of metal in
> > contact certainly would produce electricity as illustrated when a N.A.S.A.
> > contractor figured out the specification writers requiring only one kind
> > of metal for those Mars Rovers was wrong and used two different metals.
> > The batteries kept recharging and N.A.S.A. got lots more data back on Mars
> > than they expected thanks to that contractor correcting that mistake.
>
>