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Re: Voltage tester idea
My Fluke meters are all calibrated, my cheapies not so much, but I'd love to grab one of these chips. Got a link?????
Well for $2 this is a 0.1% shunt reference (like a zener).
LM4040AIM3-10.0/NOPB Texas Instruments | LM4040AIM3-10.0/NOPBCT-ND | DigiKey
It needs a bias current (100uA to 15mA) though which could be as simple as a resistor to 12V (perhaps a lighter plug outlet) or you could get the 1.225V version and use a couple batteries with a resistor and a switch.
I'm also curious what hello has got.
Edit: I'll also add that as far as cheapies go the one I linked earlier is pretty damn good. Auto ranging, shuts off automatically, buzzer for continuity and it includes internal space for the (small) leads under a cover that doubles as a stand. It's ideal for throwing in a tool bag. When I've had it next to a fluke the accuracy has been near dead on.
The purchase I regretted was the $35 meter I bought. That one failed on me. Lesson learned. I'll try to stick to things that are either really good or really cheap. It's hard to go wrong that way.
Last edited by asdf38; 11-16-2012 at 01:35 PM.