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Date:	Thu, 5 Mar 2015 11:21:00 -0500
Message-Id:	<201503051621.t25GL09H018380@envy.delorie.com>
From:	DJ Delorie <dj AT delorie DOT com>
To:	geda-user AT delorie DOT com
In-reply-to:
	<CAF3uCZ=G0FztqBtpfvssYCz9WrUORX8+J45xmH9+KutaX6c+gw AT mail DOT gmail DOT com>
	(message from Adrian Pardini on Thu, 5 Mar 2015 12:34:44 -0300)
Subject:	Re: [geda-user] [OT] Temperature sensor and control recommendation
References:	<CAF3uCZ=G0FztqBtpfvssYCz9WrUORX8+J45xmH9+KutaX6c+gw AT mail DOT gmail DOT com>
MIME-version:	1.0
Reply-To:	geda-user AT delorie DOT com

> I'm facing the need to control the temperature of a small sample in a
> chamber between room temperature and about 450°C with a precision of
> 0.3°C or better.

I use a thermocouple to monitor my woodstove, but I don't care so much
about precision.  I use a DS2760 thermocouple kit from Parallax for
it, and a high-temp thermocouple probe from Omega.com.

For monitoring my geothermal system, I used RTDs and an MCU's ADC to
measure them.  I got extra precision by doing each measurement 64
times and averaging, and the tech who calibrated my geothermal system
says they're spot-on.

I use the same averaging trick on my thermostats to get 0.1F readings
on a 1C-rated sensor.  If your sensor isn't noisy enough to use this
trick, you can always add noise - you're basically building a 1-bit
ADC.

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