Hi all
I'm looking at experimenting in radio circuits (crystal/powered receivers/transmitters), mostly out of interest.... I note many varied uses of germanium diodes - is there any particular ones I should get hold of before I start? Help me spend some money on ebay!
cheers
Lee

 

The most popular, inexpensive, readily available is 1N34A.

 

Thanks - just looking down an ebay listing, there seems to be several others - is there any reason to get a few different types? Will others offer any advantages, or learning points??

 

Not really, not for a Ge signal diode.

 

If you are looking to acquire some commonly used components for getting started, look at this list:

http://forum.allaboutcircuits.com/showpost.php?p=531470&postcount=19

 

I made that mistake a few times. No reason to buy an assortment unless it's the kind of circuit where you might blow up the part. A germanium diode in a crystal radio circuit is pretty safe.

 

there was a comparison of germanium diodes made a while back on a crystal radio page, but that page got hit by hackers and died. there is an actual difference between diodes used in crystal radis, but the 1n34 was one of the best, and the only ones that beat it were expensive rare special purpose diodes. some like shotkey diodes with a little bias added.

 

Various diodes for crystal radio sets are compared and analyzed here:

http://www.oldradioworld.de/gollum/analysis.htm

For the purposes that the op is suggesting, the 1N34A germanium diode is the best choice.

 

Hello,

Here is an other page with tests of several types of diodes:
http://www.lessmiths.com/~kjsmith/crystal/dtest.shtml

This is one of te pages of the crystal radio page of kjs:
http://www.lessmiths.com/~kjsmith/crystal/cr0intro.shtml

Bertus

 

Thanks for the advice/links.....
I grabbed a pack of 1N34A's, and a few other types while I was at it, can't hurt to have a few in the parts box!