Re: 2101 Pulse gen repair report
Hi Michael,toggle quoted messageShow quoted text
I expect the same transistors to be good subs for the actual output amp, too, so if the thing blows again, I'd give those a try. I don't know what Tek sorted for, but a (very) crude proxy for ft is 1/BVCBO. Lower breakdown voltage is correlated with higher ft. So if you find the risetime to be marginal, that's one sort you can perform to identify the most promising candidates (assuming you have, or have access to, a curve tracer).
And the 2N918 family includes a great many different part numbers (the 2N918 is sort of the 2N3904 of ~1GHz transistors). Even though through-hole parts are obsolete (or at least obsolescent), I've never had difficulty finding hobbyist-level quantities of devices in that family. Most recently, I bought a handful of 2N5770s from our own Brad Thompson. Those transistors are part of the 918 family. That part, as well as the PNP complement (2N5771), are good to keep in the junk box.
Sent from an iThing, so please forgive the typos and brevity
On Apr 16, 2021, at 4:39, "Michael Dunn" <firstname.lastname@example.org> wrote:
Thanks Tom, tho, a few notes: