[sdiy] transistor substitutions for BC108, BC187

[Mike]

> The BC548 is the recognised sub for the BC108, but a BC550 will be just
> as good I would have thought.
>
> I think the BC187 is a PNP, but the schematic will confirm this, so it
> could probably be subbed with the BC560.
>
> Pin outs will be different though.

Tony is spot on. According to my ageing copy of 'Towers', BC187 is a PNP,
Vce 25V, IC 100mA, Hfe 50M min, Hfe 100 min.

Towers Lists 2N3965 as an equivalent, though with slightly different pin out
BC559.560 should be fine.

TUP, TUN....Yep, I bought Elektor in those days too!

A thought, this has just fired some random neurons in my very mnomonic
memory. Has anyone got a very early copy of Elektor with a TTL composite top
octave generator in it? I accidentally left over half my Elektor collection
behind when I moved house, and the demolition men buried them. It was
definitely pre 1975. I used it in a primitive organ/polysynth I built as a
student, because I could run it at 16x frequency and do wave synthesis, and
mad things like pitch bend and octave tremulant. I can't remember the
circuit at all, except for the fact it used a number of frequencies combined
by 'wired OR', then divided down to reduce jitter.

Mike