> So if the BC547 has similar specs to the 2N3904, it seems madness to
> expend great energy and shipping expense to source one of those when
> the other is widely available locally.

My aim with "jellybean" transistors is that they have GREAT specs for
most purposes AND cost less than most alternatives (better cheaper
faster choose any 3). So you can "just use them".

eg BC327-40/BC337-40/ BC807-40/BC817-40
hile these are notionally "European" parts, many many US distrobutors
have them at good prices.
(eg see www.findchips.com)

Superb Beta (current gain)
Good saturation
500 mA Ic
Vc 45V good enough for most uses.

95% to 99% of the time you can use one of these and it will have as
good a spec for the task as anything you would have used by design.
For a PIC gate driving a load or a audio ish digital filter or long
tailed instrumentation pair or ... it will often fill the bill.
Occasionally you need something better, but you know wham that is
because you are doing something special.
It's then you get out the Zetex catalog ... :-).



     Russell
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