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Ammeter

A project log for Precision current generator

A useful tool that injects small currents into your circuits, below the range of your usual lab PSU

Yann Guidon / YGDESYann Guidon / YGDES 07/13/2018 at 00:030 Comments

For the current display, I have hacked a  JT-033A :

It's a decade-old device that was laying unused in my multimeters bin, because its probes were damaged.

The autorange does not work in the very low currents :-( but it's sufficient for the 20mA-0.1mA range.

It's powered from two alkaline coin cells, at 3V. I replaced them with a battery holder for AAA batteries.

The rotary selector is removed and the contacts are shorted by solder bridges.

I'm glad I didn't damage the LCD screen :-D

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