Re: [APML] 2 More ST-4 questions

["John C. Mirtle" <jmirtle@shaw.ca>]

----- Original Message -----
From: "Alan Voetsch" <critter12952@yahoo.com>
SBIG about thermal shutdown, and/or the cold, miserable, damp, cloudy
weather moves somewhere else. This has been one of the coldest, wettest
Aprils on record, and it sucks.

    Ha! Got you beat - we are in the middle of a full-blown blizzard. It's
chest deep with snow in parts of my yard, and it is supposed to keep snowing
until Monday. Looks like this new moon is a wipe-out as well. As for the
ST4 - last time I measured the current (1995ish) it consumed 1.1 amps of
current. 900mA of that is drawn by the peltier cooler. It is well under 2
Amps, which I believe is the power sucked up by the STV.
    As for thermal warm-ups, IIRC the whole point of this was to reduce the
chances of damaging a chip due to huge temperature extremes across it's
surface. The TC211 in the ST4 is so small physically that I don't think that
this was ever a problem. SBIG have not introduced this feature either into
the firmware (front panel) or in any of the control software for the ST4. As
far as I understand it, this isn't a problem with the ST237 chip either (the
STV and ST237) but it might be a concern with larger chips like the ST8 and
up. Or, maybe it's a marketing conspiracy by software vendors........ :-)
Heck - move to Canada, you never have to worry about heat problems!

John Mirtle
The Great White North!

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