jimbob jones
New Member
Im building a simple crystal reciever set. I am wondering if the diodes used in the detector stage have to be germanium diodes. And why is this?
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jimbob jones said:Im building a simple crystal reciever set. I am wondering if the diodes used in the detector stage have to be germanium diodes. And why is this?
Definitely! That's about 90% of the overall crystal set experience. My first crystal set was of the oatmeal box variety, back in about 1955. I bought a Philmore galena crystal embedded in a soft alloy (solder?) for about 25 cents from a local store (was Radio Shack around then?), then hunted all over town for #26 double cotton covered wire. Finally found some at a motor rewinding shop. I had no idea what the cotton was for, although I'm not sure I could have found enamelled wire any more easily even if i had known it was an option.Nigel Goodwin said:If you'e doing it 'properly' you should use a lump of galena and a 'cats whisker', and NOT a germanium diode 8)
Nigel Goodwin said:jimbob jones said:Im building a simple crystal reciever set. I am wondering if the diodes used in the detector stage have to be germanium diodes. And why is this?
Yes they do, because a germanium diode has a far lower voltage drop than a silicon one, a silicon one requires around 0.7V to conduct, a germanium one only requires something like 0.2/0.3V (going from VERY distant memory!).
If you'e doing it 'properly' you should use a lump of galena and a 'cats whisker', and NOT a germanium diode 8)
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