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Subject: Re: [geda-user] Soldering Station suggestions
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From: Dave McGuire <mcguire AT neurotica DOT com>
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Date: Mon, 14 Oct 2013 22:31:41 -0400
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  Umm, unless I'm mistaken, the SmartHeat irons (which includes the SP200, not sure about the MX500) uses an RF impedance-based sensor to determine the amount of metal mass next to the tip, and beefs up the heater current to match in real time.  I'm pretty sure I have a schematic of that somewhere.

             -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA


On Oct 14, 2013, at 9:59 PM, DJ Delorie <dj AT delorie DOT com> wrote:
> The Metcals don't use electronic temperature control, they use
> Physics!  The tips are only magnetic up to a specific temperature, and
> only accept energy from the coils within when they're magnetic, so
> they "just stop" heating up at that temp.
> 
> Tips are available in a range of temperatures, from 500F to 800F.