Is there a way to identify transistors with house numbers?

[Chris Goodson]

I've got piles of circuit boards from all sorts of junked electronics and while I can always find resistors and caps I need from them the transistors always seem to be oddball numbers.  I know some of them have got to be usefull ones for pedal building, so I there a way to find out?

[petemoore]

I soldered  three lead wires off of the bottom of a piece of perf with a transistor socket in iit. I stick that in my DMM's Hfe tester...I stick Q's in there to determine whether they're NPN or NPN, what Kind of gain they read [no leakage detection] then sometimes just stick em in a cct with whatever polarity they use, to see what they do.

[Mark Hammer]

There is "house" and then there is "house".  The NTE/ECG catalogue is capable of cross-referencing a large number of  semiconductors that seem to be completely off the radar.   It won't identify them ALL, mind you, but I've been pleasantly surprised by what I could find in there.  It will, of course, cross-reference them to NTE products, but that can often be enough information to figure out what the nearest non-NTE equivalent might be.  So, if you find an RF56TX cross-references to an NTE123, then you'll know that it is more or less the same thing as a 2N5088 or 2N3391 or BC549, and that there is an excellent chance you may be able to just plunk it in where you would use those.

Occasionally, there are posted lists of house-number equivalences.  For instance, there is a list posted somewhere, of house numbers for parts used in Electro-harmonix circuits.

[Chris Goodson]

I found some free cross-reference software here that seems to be helpful in finding a lot of what I have.  Their resistor program is sort of cool too.


http://www.moyerelectronics.com/index.html

To anyone interested it's in "free software" towards the bottom of the left frame.

I have one board from a Crate amp that has a bunch of J112's and J176's on it, I'm hoping maybe they would be good for a distortion pedal.  Anyone familiar with these?

[Jered]

The J112 fet is an N-Chan chopper/switch the J176 is the same but P-Channel. Probably won't sound to good not to mention choppers are an absolute bitch to try and bias. You could try the 112's in a minibooster since its self biasing but still might not sound to good.
Jered