Germanium diodes prone to heat damage?

sch929 · Post by **sch929** » 10 Jan 2011, 04:57

Are Ge diodes, like the 1N34A Ge, prone to heat damage from soldering?
The measured resistance of a few Ge 1N34A that I have has are ~2ohm which seems silly for a diode?
The diode was not biased, that was just a DMM measurement.

lolbou · Post by **lolbou** » 12 Jan 2011, 08:24

sch929 wrote:Are Ge diodes, like the 1N34A Ge, prone to heat damage from soldering?

As any semi-conductor device, I would say yes. Use a pair of pliers as a heatsink whenever you can...

sch929 wrote:The measured resistance of a few Ge 1N34A that I have has are ~2ohm which seems silly for a diode?
The diode was not biased, that was just a DMM measurement.

A DMM ohmmeter acts as a constant current source (some µA or so). Then it measures the voltage drop accross the probes, and compute resistance according to Ohm's law. I don't know what to expect from a single diode, but if you have a DMM, check it with the diode function?

Now, was the diode actually soldered on the PCB? Measuring DC resistance in circuit can give weird results: there are sometimes other paths to link your two probes.

DrNomis · Post by **DrNomis** » 12 Jan 2011, 10:53

The funny thing is,even though Germanium is heat sensitive,I have never in my whole life ever damaged a Germanium diode by overheating through soldering,I have my soldering station set to 350 degrees C,and have never damaged any semiconductors at all.....

I think as long as you are careful,you shouldn't damage any semiconductor devices.....

sch929 · Post by **sch929** » 13 Jan 2011, 22:53

Thanks guys. I'll try to scrounge up a better multimeter with a diode function.
I had heard about Ge diodes being fragile for a long time, so when sorting old parts I became suspicious of the ones on hand.

DrNomis · Post by **DrNomis** » 13 Jan 2011, 23:10

sch929 wrote:Thanks guys. I'll try to scrounge up a better multimeter with a diode function.
I had heard about Ge diodes being fragile for a long time, so when sorting old parts I became suspicious of the ones on hand.

Germanium is a funny semiconductor material,I've read somewhere that it can be disolved in water,it is temperature sensitive,more so than Silicon.....