Expo conv. heater (tomg et al.)

[Tony Allgood]

Hi,

All this talk about ovens for keeping drifting under control. I worked
on Peltier temp controls in microwave detectors. Now these peltier heat
pumps are really good. They can be glued into place, ie. on top of your
3046, and you can make them hot or cold depending which way current goes
through them. Mind you they are expensive, 20UKP for a small pump, but
that could keep a few VCOs happy with some careful metal work. Oh and
the current draw can be quite large, we used +/- 1A, but that was to
keep it to with 0.1K. Op-amp servo loop with a small class B power amp
controlled the temp. PWM could be used, but these are noisy. You could
fix the temp at 290K, wrap in polystyrene, except for the heat sink, and
say goodbye to drifting expos. It wouldn't help other drifts like the
timing cap, CV resistors etc. but would really be rather cool.
Literally.

I had five small pumps on a heatsink to keep my drinks cool in the
summer. Now what would be rather good is to build one onto the substrate
in an integrated VCO. Tony Clark was going to do some small VCO
hybrids... perhaps this is the answer to drifting:-)

Regards,

Tony Allgood, Cumbria, UK

e-mail: oakley at techrepairs.freeserve.co.uk

Rack mounted Moog VCF module. Details to be found at...

http://aupe.phys.andrews.edu/diy_archive/schematics/effects/filter.html