Crystal Radio Home Brew Vernier Tuning 3 Coils 2 cylind 1 Spider Web 2 Detectors For Sale -

1. Home Brew:
2. Vernier Drive Tuning;
3. Three Coils two cylindrical one Spider Web;
4. Home Brew Cats Whisker with Galena Crystal;
5. One fixed diode;
6. 1/4 inch Headphone Jack;
7. Fahnestock Clip Headphone Jacks

Recommend: For more Fun & flexibilityGillette Blue Blade Crystal Radio Detector Kitand/orCrystal Radio Experimenters Detector Radio Experimenters Detector KitAs you can see in the picture\'s you get the Razor blade kit i already offer, plus Iron Pyrite and Galena, an extra pin for the Galena and Pyrite with no Pencil lead, and a brass plate to mount the Galena as in the picture, also 2 diodes to test out, one 1N34A and a Schottky Diode. Besides what is in the picture I added 3 more screws and 2 washers to the Blue Blade Crystal Radio Detector Kit Razor blade has been dulled to protect the builder.Gillette Blue Blade Crystal Radio Detector KitDuring WW2 the boys on the front used this blue razor blade idea that Cornell came up with to listen in on the news and music. Gillette came up with an idea to blue coat his blades to keep them from rusting and as it turns out they rectify because of it with the combination of the carbon pencil lead.Must have been a stroke of genius on Cornell\'s part to think of such a wild idea. In practice the way it works is you move the pencil lead over the lettering and the stations start coming in and it just about works like a galena detector of the 1910 era because when you move the lead around you can sometimes change stations or make the one you want clearer.I personally built the blade radio in 1957 and again in 1962 for an electronic class project. hen I went to the Library one day I was looking around at electronic books and ran onto a book on how to build the razor blade radio. could have been written by Cornell I don\'t knowI latched onto it and knew I could build it, it was fun!The razor blade supplied is a genuine 1930\'s blade as used by Cornell to build his radio. As can be seen in the second picture the lead is wrapped on with silver plated copper wire and super glued to the safety pin and with care should last a lifetime.Parts in this kit1 razor blade 1 safety pin with pencil lead attached 2 washers 3 screws
Antennas cannot be too long for a razor blade radio or Crystal Radio, the longer the better up to say 234 feet that would be 1/4 wavelength for 1000kc the middle of the AM band. The formula for end fed antennas is \"length feet = 234/frequency a dipole would be \"length feet = 468/frequency. A crystal radio operates on the signal strength only and the stronger the signal to the radio from the antenna the louder it sounds. so the more wire you can get up the better they work.But on the flip side of all this if you can put up a full-length antenna the stations start to pile up on top of each other so then for this radio setup you need the best selective radio circuit you can come up with.I won\'t put it up here anymore I have my reason but if you want to send me a note through and I will send you a diagram I re-designed from world widely accepted as the best circuit available for a crystal radio. It uses 2 diodes and separate antenna and receiver circuits inductance coupled so not to load up the receiver end.
Headphones or speakersSeems its really hard to come up with a decent pair of headphones, so hears a trick someone came up up I cant lay claim to it, but use a battery or wall power computer speaker to listen in, cut off the 3.5mm plug off the end of the speaker PC connecting cord and strip back the outer covering, the wires have 2 types, plastic covered or varnished. The plastic will have a copper shield around two wires the shield both of them can be twisted together and the 2 wires you strip them and twist together. Then connect the 2 twisted together wires to the headphone posts or clips. The varnished wire type has colored varnish.. strip with a knife the colored off all wires and twist together the green ones and the other 2 together and connect to the crystal radio. Or you can buy a stereo 3.5mm jack and wire that up and not do any cutting. Rich

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