ComputerVoltageSources

Re: matching resistors, will the following procedure work?

Ingredients:
	1 precision voltage reference
	1 amplifier
	1 voltmeter
	Resistors to be matched (RTBM)

Feed a small, precisely regulated signal through a voltage divider 
made from an RTBM and some other resistor (the "constant"). Feed the 
divider's output through the amplifier. Measure the output. Repeat as needed.

The idea, obviously, is to amplify the differences between the RTBM 
so that the voltmeter can register those differences. Concerns would 
include temperature stability, power supply stability, etc...

So, this may not be good enough for a NASA guidance system, but will 
it suffice for this DIY project? As John Lofflink said, we need only 
be concerned with relative accuracy.
--
john