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How can I safely mount a TO-39 in a TO-92 location?

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Sir Knight:
A recent build on an amp has me up against a wall. The board is drilled for a TO-92 package, with 3 pins in a straight line. The part to be installed is a TO-39 (TO-205AF) with the 3 leads in a triangle configuration. The prototype I got from a friend has the TO-39 stuck in the relevant spot with the leads bent to fit the inline holes of the original transistor . I'd rather not do something so kludgy. I'm wondering if there is a such thing as a pin adapter/socket that I could mount on the board and then just press my 39's in there. I recall someone telling me a long time ago that there were various sockets that could be added to boards to accommodate something like this. A reasonably thorough search has turned up nothing, but I'm sure if it exists someone here would know.

Or should I just grab some hobby board and lay out an adaptor myself? These are for a stereo differential pair, so they're all right next to each other in a line - maybe I should just stand a little phenolic table off the main board and do it that way?

Or is there an even simpler way to do this and I'm just not seeing it? Advice, please!

Just form the leads, nothing hacky about that. ???

More to the point is whether the fat can fits around neighboring components, but I guess you aren't having issues with that so it's okay.

Another question is, why TO-39 at all?  Such devices are largely archaic.  A TO-92L or TO-126 would be more modern I suppose.  Or if the power isn't needed (as "diff amp" might suggest), plain old TO-92 should do.


David Hess:
TO-126/TO-225 parts were never released in as wide a variety as TO-39 parts.  Maybe the circuit uses something exotic by modern standards?

I have the same problem with my old function generators which use TO-39 output transistors for which no modern replacements exist.

Speaking as a person who has performed countless repairs in a professional environment, I can definitely say that there is nothing unprofessional about just bending the leads. A home brew adapter would be a kludge IMHO and totally unnecessary. On top of that, it introduces several new points of failure so it makes the adapter an actual negative element.

There used to be plastic adapters, about 1 mm thick, with molded holes to neatly force wires from one transistor package type into the hole pattern for another type.  I used to have a set of these on a paper backing from the vendor, but they are long gone.  Used properly, the transistor would then fit firmly into its new home.


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