somethin curious....from inside a transistor

[bogdanfirst]

i found an old transistor, germanium type, i think it was something from the AC1** series.
i squezed it and something white came out of it, like a toothpaste, it looks like a gel, not liquid, but not solid.
is it normal to find such a thing in a transistor...?
another think to mention, the case is metalic, cilinder, about 6.5 mm in diameter and 9.4 mm long.

 

[hantto]

Hmm... Maby it is thermal silicone compound?

 

[bogdanfirst]

well i dont know, i thought that transistors only contain solid parts.
maybe is some sort of heat counducting material that has the purpose to conducting heat from the silicon cell to the case for cooling, considernig that i think it was capable of suplying 1A or something like that

 

[Sebi]

Yes this paste similar as thermal compound,and You can find most of Ge transistors inside, because these devices have more sensibility for heating.A Ge transistor C-E always have small conducting, and this depend from room temperature. If You can studying an old AF PWR amp.cct.with Ge transistors can see always a thermal compensator NTC.
When i was young i`ve made from OCxx glass-housing Ge transistors quality light-sensors....

 

[bogdanfirst]

yes that is right i can find temperature compensating NTCs. so, one more "electronic mistery" solved.
thanks for the reply.

 

[McGuinn]

Some people may remember that old Germanium diodes came in a glass case coated in black paint (OP91... could that be them???). They had a clear gel in the bulb surrounding the contacts (to prevent oxidation?) and if the black paint was scraped off, the device could be used to detect changes in light... The clear gel was changed to a white paste later to prevent them being used in place of more expensive LDR's...

 

[Mat]

deadly contents

Some semiconductors contain a level of toxic substances, ie arsenic be carefull.

 

[Sebi]

Yes, the high frequency power transistors and small TX modules in GSM-phones!

 

[bogdanfirst]

thnaks about the advices. i tried not to touch the white stuff.
anyway i thought about it being toxic, so i was careful.

 

[Chippie]

The white "toothepaste " substance is Beryllium Oxide quite nasty!! Avoid contact with it.

 

[Dave the Embalmer]

Yeah, Chippie nailed it, its thermal paste. Word of warning: Its very nasty stuff, very toxic. Obviously, don't eat it. It can be fatal in relatively small quantities. Secondly, don't sniff it. Its probably more benign in terms of inhilation in paste form, but it can cause serious breathing disorders even with limited exposure to the dust. Oh, and it causes cancer.

Have a nice day.


Joking aside, be careful with it.

 

[bogdanfirst]

thanks, like i said i didnt touch it, nor ate it.