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i need a detector for my crystal set, PLEASE HELP Answered

i need a detector for my crystal set,but don't want to use a geranium diode or that  "cats whisker detector" that i cant get to work. PLEASE HELP ME, I NEED HELP!!!

the cats whisker detector i used was a blued piece of steel / carbon (or pencil lead) from Youtube:  
[search]    [make magazine foxhole radio]  

if a mineral like geranium, galea, iron pyrite (fools gold) work well, i would like to  know how to obtain it without buying anything online?

(i mainly don't want use a geranium diode because one i had burnt up. another reason why i don't want a 1N34A is because it isn't available at any "real physical" stores (like Radioshack )

i don't mind to use another type of diode.

what about a schottky diode? do they sell any @ radioshack? and will it work?


Actually, germanium components (diodes and transistors) are still available, you just have to know where to look. MCMElectronics has the 1N34A germanium diode listed (currently out of stock, but to be in stock soon). Also, you can use a 1N914 small signal diode (used in many kits for crystal sets). MCM is the only major supplier that lists any germanium transistors in their catalog.

Here's a link to their 1N34A page: www.mcmelectronics.com/search.aspx
Here's their 1N914 page: www.mcmelectronics.com/search.aspx

Mouser has them also (1N34A): www2.mouser.com/Search/Refine.aspx
1N914: www2.mouser.com/Search/Refine.aspx

Allied has 1N914's: www.alliedelec.com/search/searchresults.aspx
Same for All Electronics:www.allelectronics.com/index.php
As does BGMicro: www.bgmicro.com/index.asp
Antique Electronic Supply has 1N34A's: www.tubesandmore.com/ - search for 1N34A

Good luck on your repair.


can i get the1 of the 2 diodes you mentioned from radio shack?

A quick check at RadioShack.com shows that they carry the 1N914. Your local 'Shack may or may not carry it. They have no listings for the 1N34A.


thanks 1n914 WORKS  i hear the loud POP!!! i haven't lisened for radio waves
its disappointing that geranium diodes don't come easily though

well it works for powerful emf but turns out it dont work for radio waves

actually now my 1n914 diodes are testing out @ 0.6 voltage drop but as i read up on Schottky diodes, they have an extremely low voltage drop! some lower than geranium 1n34a diodes!!!! do you know if i can use them?

I've read reports that people have used them specifically since they have such low thresholds. Couldn't hurt to try.


and i cant find them at the shack... i think its just because im looking for them and not for a part number.are you talking about which type? and what is a threshold?

Quercus austrina,do you know if any stores that sell 1n34a diodes or crystals? or other types of geranium diodes?

One important point about detectors is that since you have no power  other than what comes down the aerial to operate them they need to operate at very low voltage (1) .
(2) Germanium and Silicon are the most used, however Silicon needs 0.6v to operate and Germanium only needs 0.2v so the latter is more suitable for the low signals in a Crystal set.
If you blew your diode you must have used a battery or had a lightning strike.
Trying to get a catswhisker to work will try any ones patience
and as for razor blades and lead pencils God help us. you have very little chance.
If you have any old Germanium type Transistors-maybe from an old Radio use the Emitter/ Base  leads as a diode, any way round will do as there is no power applied.
You need a very strong Station near you and it must be AM not FM, there is a different type of detector for FM.
Hope this helps.

thanks but where can i get geranium from?  no geranium items @ radio-shack.

can i use a 1N914 for it (I'm purry sure the answer is NO because i cant get it to work. i already tried them )

can i grow a crystal that will work like pyrite (fools gold)? 

also, i think if the coil and variable capacitor was VERY small to pick up higher freq. it would pick up

I've been missing for a while and did'nt see your reply I suppose by now you will have solved it, or moved on to other things, anyway just in case you can get the diode from scitoys.com for 84 cents US. have a look in their catologue for lots of radio parts.

i have a piece of fools gold, i am experementing with it i bought it from a rock shop at luray caves


8 years ago

Quercus austrina , do you know of any stores that sell geranium diodes?

Most any diode should work.  If you live in the US any radio shack will have several to choose from.  They don't have to be germanium.

i have a small bag full of rectifiers, diodes, and other stuff but most of them dont work at all while a small red one just barley works..  =(  any other ideas?

i test buy connecting a transformer to a battery then disconnect it fastly make a POP & a burst of radio-waves.

on the crystal set with 1n34a diode, i get a loud POP(and little ear ringing) threw the ear piece but with the small red one gives a small faint click threw the ear piece. and every time a little less sound. so i think it builds up charge like a cap.

If you cant find one I will send you a germanium diode.  I am sure i have some in my parts bins from years ago when i built lots of electronics items.  However, you must be willing to email me back with your address and I will send you one... if you live in the USA. If you live outside the USA... then sorry, I don't want to send it overseas.  I will send it to you free.  email me at framistan@sbcglobal.net

no thanks i'm good.     rather buy it than take one from you  *,* 

I'd probably have to build one myself to be more helpful I think.


If you've got a crystal set it should have a crystal in it. What have you got there that doesn't work?


yes, but while experimenting with my crystal set, a voltage spike destroyed it to the point it conducted both ways.

Oh right. Well you got a good answer already, I'll not start thinking about replacement crystals 'cos that's why people created diodes...


Get yourself a copy of the book "voice of the Crystal" to find out how to make a cats-whisker diode work.