[volt-nuts] High precision calibration for the poor man

[Poul-Henning Kamp]

In message <01e601cb70a1$58aa9150$09ffb3f0$@canardpc.com>, "Samuel DEMEULEMEEST
ER" writes:

>I'm now looking for a very precise way to step-down the
>voltage (-70 µV) in order to achieve the rated accuracy needed to calibrate
>the meter. That accuracy doesn't need to be maintained for more than one 
>or two minutes.

Have you tried simply grabbing one of the plugs with your hand to
change the temperature of the metal-metal thermoelectric effect ?

70 microvolt may require more than a warm hand, but the principle
can be trivially extended with more sensitive junctions.

Poul-Henning

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