Transistor matching - my results

[Magnus Danielson]

Hi Roy!

> Here's my second shot at using the Moog transistor matching
> schematic.  After changing the schematic (I had a jumper to V+ 
> that should have been V-) I started getting results in line with the
> 0.6xx mentioned in the paper.  I also switched to a 1 amp +/-15 V 
> power supply.  Here is the test data for my first matching session on 
> 17 NPN 3904s:
> 
> 1 x 0.5942
> 1 x 0.6013
> 1 x 0.6060
> 2 x 0.6064
> 1 x 0.6067
> 2 x 0.6070
> 1 x 0.6086
> 1 x 0.6110
> 4 x 0.6127
> 1 x 0.6128
> 1 x 0.6134
> 1 x 0.6136

This certainly looks like the rigth thing!

> The paper says that a match is +/-0.002 V or 2 mV, so I have several
> close matches as well as a few very good matches.

You seem to have 4 really good pairs and a couple of more pairs which is almost
as close...

> BTW, as before I was using a Fluke 8060A digital meter.  I think it's
> working now.  I've toyed with the idea of taking readings in a heated
> room and getting the slope for curiosity, but who knows.  BTW, some
> digital volt meters have hfe measurements, using 3V and a few milliamps,
> would their measurements be significantly better than what I'm doing?

Well, in a way is hfe measurements doing something diffrent...

> And a special thanks to Magnus Danielson for keeping me honest.  :)

Thanks! :)

Cheers,
Magnus