[volt-nuts] Precision resistor testing

[Richard Moore]

I’ve built a little box with two 10kohm precision resistor assemblies, using Fluke resistors — one ass’y is two 20k managing wire on shellacked mica cards in parallel, and the other is made of eight 5k wire wounds in sealed green plastic cases in series/parallel. These are not exactly 10k ohms each, but are about 30ppm (high) for the mica card, and 20ppm (low) for the green plastics, according to my HP 3458A. 

I would like to get them accurately characterized, but never having done this, I don’t know who to have do it or how much it would cost. Any ideas or suggestions? They can be shipped anywhere cheaply as the box is small, light, and very durable.

TIA