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Identify this Germanium transistor???

Started by aran.e666, May 11, 2017, 05:15:49 PM

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aran.e666

hey guys,

long time since i posted here but i'm back. I'm asking this here as i'm really not too sure where else i can ask this question :D

anyways, so recently i acquired some nice USAF stamped 2n404's from Ebay. i noticed however one transistor was very dirty and also in a different style package when i was testing the hFE. either way, i still tested it. i think it measured 470 hFE  :o (yes, i know it's not true hFE but still much higher than the 404's i tested). that's when i noticed that there were more of the same transistor. i found one that was fairly clean. its made by RCA and says 'CIA' (or C1A) with what looks like '3621A'. yes, i know, CIA isn't Central Intelligence Agency but just some identification tag probably. my question is - what is this? are there any similar transistors? i ask because i can't find any info on it. maybe i didn't look hard enough which is why i'm asking here for someone to point me in the right direction.

~Aran
Guitar is love, guitar is life.

jimilee

Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

flanagan0718


aran.e666

thanks for the replies guys, much appreciated.

i searched in the discontinued transistors and i found a '2N3621' but it seems its not the same

as for the small signal transistors pdf, yeah, its actually nice to have as i never thought to search for it before.

i'm sure we will figure it out :D
Guitar is love, guitar is life.

flanagan0718

I actually have an ass load of Germs to go through if i find any in my stash ill let you know.

ASS LOAD


aran.e666

that pic reminds me of an old teacher i had. he came from Canada to the UK for a year to teach electronics. he had this cabinet in his classroom so he decided to show me inside when he found out i love electronics. it was filled with this HUGE collection of germaniums :D
Guitar is love, guitar is life.

aran.e666

Guitar is love, guitar is life.

EBRAddict

This ham operator has a 1957 and a 1960 RCA product sheet for discretes:
http://n4trb.com/AmateurRadio/SemiconductorHistory/SemiconductorDocuments.htm

I didn't look carefully but I didn't see anything with 3-6-2-1-A or partially in that sequence. It looks like all their transistor products start with "2N"



midwayfair

It's not germanium. There are plenty of silicon in the TO-5 package.

Anything with 4 numbers after the 2N is going to be silicon, and you can be reasonably sure that anything in a TO-5 package is intended for medium voltage applications (think 50-100V).

It's probably a 7, not a 1.
http://alltransistors.com/transistor.php?transistor=3412

aran.e666

thanks for the replies,

i'l have to look at that site and see if i can see anything myself.

also Midwayfair, i never actually thought of it like that. i took a look at the datasheet and it makes sense. i suppose it would make sense that it is a 7 too. i would test it to see if it's npn but for some reason the transistor socket on my DMM is blocked up.

i also got in touch with the semiconductor museum and this is what they had to say: "The other unit, type "3621A" is similar to many other RCA "in-house" numbers made for a specific customer, often a computer manufacturer.    I haven't seen the CIA text before, so this type might be actually a special order for the CIA."

i suppose the only real way to know would be to contact RCA but considering they shut down in the 80s makes it impossible. another thought i had was asking the original seller where he got them from buy he said he bought them from someone years ago.

i would still love to know what the CIA means. i think its just RCA's markings as most of my RCAs have random letters on them.



Guitar is love, guitar is life.