[volt-nuts] DIY Air bath

[Poul-Henning Kamp]

In message <CAE6XXriOVmmkLr2K6jZFdHurtYbYyCbGZcRLExQ=rvMcDFk2jw at mail.gmail.com>
, Will writes:
>Poul-Henning Kamp wrote:
>
>>Actually the major trouble with Peltier is controlling them, because
>>they are asymetric with respect to transport direction.
>
>I think the negative feedback of the control loop helps with that,
>unless the difference is so big that it requires different
>compensation for cooling and heating to be stable.

Depends on the temperature difference but I seem to recall that it
is something like 1:3.

The problem is that once you get to your target temperature, it will
fuddle around with the small residual noise and because of the
asymetry it actually amplifies the noise if you don't do something
to prevent it.

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