[sdiy] Potted expo converters

[Tom May]

Peter Grenader <peter at buzzclick-music.com> writes:

> Ladies Tangents,
> 
> I remember one day I got all excited at this brainstorm I got that you could
> (sort of) duplicate the functionality of the ua726 by using the remaining
> trannies in a 3046 as a self heater, only to find it had been done a billion
> times before when I posted the idea on this list.
> 
> d'OHI!
> 
> So, here's another lightbulb that appeared over my head that I'd thought I'd
> bounce off you all  that I'm also willing to bet ain't original, either...
> 
> I remember when I was an engineering tech two billion years ago, we used to
> glue thermocouples to the windings of 1/2 horsepower electric motors using
> thermally conductive epoxy for UL lock-rotor tests. the material seemed to
> be was astonishingly heat conductive. But...we were dealing with
> thermocouples which could detect a match being lit in the next room (not
> really of course, but you know what I mean).
> 
> Along the same lines, has anyone tried potting the tempco/expo converter
> pair in conductive epoxy to A) improve heat transfer from one another and B)
> aid in isolation from ambient conditions?

I epoxied my MAT-02 and tempco resistor and enclosure made from
thickish but bendable copper together with Arctic Silver Alumina
(http://www.arcticsilver.com/arctic_alumina.htm).  I didn't do any
measurements but it works a lot better now (no warmup time, and
whatever drift there is doesn't seem to bother me, but I'm no
perfectionist in that area).

Tom.