identifying diodes

[Chef]

I have a load of diodes but dont have a clue what models they are.  How can you find out?  For example i have 2 diodes that i know are germanium types, they are clear but with orange ends in the middle, that is the only identifyable characteristic about them, no numbers or letters or anything.  I wanna know if i can use them in a shredmaster mod that specifies germanium 4001s.  Any clues?

[Chef]

sorry it specifies 1N4001s  (if that makes any difference).

[JimRayden]

I guess any germanium will do since they have approximately the same forward voltage.

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Jimbo

[Mihkel]

The 1N400x series are all silicon rectifier diodes, not germanium as far as I know.

[Peter Snowberg]

Grab a meter with a diode test function on it and measure the forward voltage of each one. If the voltage is under 0.45V and the case is made of glass, you probably have a germanium. If the voltage is over 0.45V and the leads are thin you probably have a silicon signal diode (1N914 style). If the leads are thick and forward voltage is over 0.45V you probably have a silicon power rectifier (1N4001 style). If the leads are thick and the forward voltage is less than 0.45V you're probably looking at a schottky rectifier. Test each diode in both directions. If you have unmarked diodes with multiple color bands they may be zeners.

1N400x devices are all silicon. The part number specifies Ge or Si.

[mac]

BTW, I have a pair of diodes I removed from a distortion circuit that used two Ge transistors. The forward voltage is 0.51v, glass case, one red band. They sound and look like old Ge diodes but the forward voltage is high. Are these Ge or Si???

mac