Crystal Set

[pwdrive]

The crystodyne, some types of early crystal detectors exhibited negative resistance long before the invention of the tunnel diode.

Crystal receivers were used during the war by the military.

The Marconi CR300 comms receiver has a "crystal set" built in so that reception could still be achieved in the event of a ships power failure, I believe it was a Board of Trade requirement.

The Crystodyne:

http://earlyradiohistory.us/1924cry.htm

Lawrence.

[boiss]

Interesting, do you happen to have the next article on the amplifying crystals?
Mike

[pwdrive]

I picked that link because it had various schematics plus a general description of the Crystodyne but there might be more info on the web.
The Crystodyne was popular with early amatures apparently.

Lawrence.