Crystal Radio Supplies

[rrogers40]

Following the radio theme I'm attempting to build a Crystal Radio but need a source for Germanium Diodes and a set of Ceramic Earphones or Buds. Any ideas of a local source?- I hate purchasing stuff online.

And although a set of the smaller "ear buds" is only like $3 online I would like a real head set.

Thanks

[dgriffin]

You can use a 1n34 diode as a detector and you should be able to buy one at Radio Shack. I use them for miscellaneous tasks around the shack. But you can get a real crystal(and cats whiskers) from
The Crystal Set Society at:
www.midnightscience.com/
I haven't ordered anything from them in years, but their shipping rates were always reasonable.
So, if you can't find what you're looking for locally, there are a couple of online places that don't charge an arm and a leg for packing and shipping.


Also, for basic radio supplies, including diodes and earphones and even basic crystal set kits, see Radio Daze at:
radiodaze.com
I don't think they carry crystals. I order just about all the radio components I need from them, because they have no packing fee, just postage from Victor, near Rochester.

You want a HIGH impedance earphone (which Radio Daze carries for $3.50), because in a crystal radio the earphone is actually part of the detection circuit and a high enough voltage needs to develop across the earphone (we're talking very low voltage from an absolute point of view, don't worry.) Time was when all earphones were high impedance, until the advent of modern gear. Today, most of the headsets, earphones and buds are low impedance, allowing them to be interchangeable with speakers. You can buy high impedance Headsets, but I haven't seen new for sale in a few years. You might have to purchase an old pair and they could be not working.

Another function of the earphone in a crystal set is to allow only the loudest local signals. Back in the old days, there was usually only one radio station around and this aspect removed distant signals which would have been heard simultaneously with the local signal.

For fun one time, I hooked the output of a crystal radio to a high gain audio amplifier and, of course, it heard EVERYTHING. It was confusing, but I heard a variety of shortwave stations all at once as they faded in and out with the vagaries of the ionosphere that evening. It was like listening to the miracle of radio and for some weeks afterward I would turn the setup on and let it play in the background. It was somehow soothing and at times funny, e.g., when a station in the MidEast bubbled to the top along with a baseball game from Cincinnati.