[geeks] While on the subject of weirdness

[wa2egp at att.net]

> Thing is, I cant replicate this on demand, because I'm not sure what
> precisely makes the diode rectifier. Probably should have paid better
> attention in chemistry. Funny, in microelectronics we did have classes
> on semiconductors and physics of materials (operating principles and
> equations for purity of an anular oven anyone?) but never came upon
> something like that.

Could be a coating on one of the metals and the metal.  Too many variables
that are uncontrolled.  At one time, experimenters in early radio did
make "rectifiers" from some type of electrolytic combo instead of galena
crystals.  Maybe that might bbe worth searching.

 
> > During WWII, GIs used to
> > make foxhole radios out of razor blades and scrounged parts.
> 
> you have an URL for that?

I wish I did.  I have seen in some publication where you could make
a "crystal radio" from one of the old "blued" double edged razor
blades, a piece of pencil lead and various pieces of bend paper
clip.  The pencil lead has to lightly touch the "blued" part of
the razor blade (that's the tricky part) to get it to work 
properly.  You need a high impedence headphone or crystal earphone
(last time I got some was from Mouser).  It was suppose to be
a copy of the WWII foxhole radio. I never built one so YMMV.
 
> > IIRC there is a website of crystal radio enthusiasts which might be
> > a source of info.  I think it is midnightradio.com
> 
> Close:
> http://www.midnightscience.com/

Ooops.  Yeah you're right.  Sorry, I was in the middle of resurrecting
my old Dell laptop (Winblows XP Pro totally blew up and wiped out
everything so I'm piecing it back together with XP Home since I forgot
the little BIOS thingy that lets Sol 10 x86 load properly) and too
much crap is floating around in my skull right now.
Window.....pffffhhhhht!

Bob
> 
> It might be a rare case where an old library might have more info than
> the internet...
> 
> Francois
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