tranny pairs

[>>>marjan<<<]

> Just out of curiosity, exactly how does one go about matching transistors.

You want best match for Vbe @ Ic=const, preferably for 2-3 values
of Ic (but often only one is performed)
see moog's matching cct (I think it's at sdiy page)

> I thinking about building an OB-1 Phase Shifter, I think that's what it's
> called, and it asks for matched pairs.  How no you do it?

Here you need matched FETs not plain bipolar transistors. You can find
nice cct at www.geofex.com under FX schematics for matching FETs in
mxr type phasers. What it does is that you bias gate of FET with
some DC corresponding to max voltage it would get by say modulating
lfo (meaning if you have lfo amplitude 2V youll bias id with dc 2V)
and you measure Vds on each FET finding best match (they work here
as variable resistors in voltage divider so you can measure
voltage instead resistance, it'll ensure that all FETs at max peak
of lfo have the same resistance which is essential for phaser to
work right).


marjan