Finding info on old parts

[savage]

I was just given about ten boxes full of electronic parts, most probably from the sixties and seventies including many jars full of new transistors and such. I have not been able to find info on most of these parts or through the few parts search engines I know of. Does anyone have any ideas on where I might find more info?
A few transistor numbers:
KA1225
T626-1
T614-2
AT2907
TN3646

And I was so proud that I had just gotten rid of three big boxes of junk from my workspace. Thanks in advance to anyone that can help.

[Enzo]

Look up 2SA1225 and see if what you get resembles that KA1225.

Looking these numbers up in NTE or ECG will tell you what NTE would use in its place, if they cross there, which would give a reasonably close idea of what your part specs are.

T626 and the other one look like house numbers to me. In fact they all look like house numbers.

I am inclined to think the AT2907 might be a 2N2907. Is that one a metal case about 3/8" diameter? (TO39 case.)

And I might suspect 2N3646.

Any chance that is a KA1Z25 instead of 1225?

All these are guesses.

[Sweetfinger]

If any of the transistors are Germanium, measure their hfe and leakage. Any that fall into accepted ranges for Rangemasters or Fuzz Faces can be used in those circuits regardless of the numbers printed on the can. The older silicon small-signal transistors generally don't have as much gain/bandwidth as modern ones, and can work well in vintage pedal circuits. Test for noise, there's a lot of variation in the old ones.

Remember to separate the germaniums with different colored epoxy on the bottom because I, (just like Mike Fuller), firmly believe that the colored epoxy ones sound better! .....well, they look cool at least :p

any "bumblebee" caps? (or later Sprague black w/orange lettering)

[savage]

most of the transistors have either TI108 ,TI107 or TI106 on them as well, but even the ones I have been able to identify have these numbers. Oh well, might have to measure them to see where they're at. Lots of unmarked transistors in t-05 case I think. Probably they are general purpose Si from that era, but is there a simple way to check whether they are Si or Ge? Lots of Ge both NPN and PNP going back to the early fifties. Yes there is a big jar of bumblebee caps, but I think the best score of all was the books. Some good test equipment too.
Friends of mine moved into a new house, and the old guy who used to live there had a repair business as well as a small radio station up above the garage. This was the stuff left behind by his family. Thankfully they just left it rather than take it to the dump. I will try NTE, I hadn't thought of that

[Enzo]

SIlicon has a junction drop of about half a volt - .4 to .6 commonly. The books always say .7 volt, but I rarely see one that high. Germanium has a drop of about half that. Set your meter to diode test and watch the drops.

[Wild Bill]

Numbers like TI107 or whatever are probably what are known in the trade as "house numbers". Normally devices are catalogue items. They have a published part number and you can look them up in a databook.

If you're ordering in big quantities like with a volume manufacturer you can ask the device makers to mark them with your own in-house inventory number. This does two things for you. One, you most likely have approved several different brands of each part to give you competitive sources. If each has its own catalogue number then having them marked with your house number instead means you don't have to care, just keep them all in the same box on the shelf.

The other thing is that now no one knows what the device REALLY is! They have to come to you for a replacement to fix the unit and you can sell it at a big markup.

House numbers in electronics are not as common anymore. The parts are so cheap that any replacement markup still isn't worth it. It was different when you were talking expensive parts to build cars and tractors. Electronic stuff is all built overseas anyway.

Anyhow, good advice for you about replacement lines like NTE. They built their business researching crosses for house numbers.

Good luck!