[Boatanchors] Crystal Radio Drives Speaker

[J. Forster]

Ken Woodside wrote:

> Hello to all!  I am requesting some assistance trying to find a copy of an old
> magazine article... The article described how to build a crystal radio that
> would drive a small speaker (with powerful local stations) without battery
> power.

I have not seen the article, but it would appear to be very straight forward. If
you took a standard crystal radio design (antenna, ground, parallel L-C, diode
detector (either Schotkey or Germaniun, for low forward voltage drop preferred),
earphone and bypass cap) and replaced the earphone with a small output
transformer ( say 2K to 10K primary and 4 Ohm secondary) as an inpedance
matching device to the speaker, it should work fine.

Good luck,
-John