originally posted by SY
The best way to measure them is either to use a four-point system (where a known constant current is passed through the resistor, and the voltage drop is measured)...........
Commercial 4-point resistance measuring equipment can be quite expensive.
You can DIY such a thing relatively cheap.
The following photo is taken from my DIY constant-current 4-point measuring adapter. It is used together with a conventional DVM in the 200mV DC measuring range.
3 precision resistors (the 2 lengthy blue things and the smaller black one aside), 1 FET, 2 batteries, 1 switch, 1 OP-Amp and that is it almost.
It is made according (with modified PCB) an ELEKTOR puplication.
Works fine!
If You`re interested I can look up which ELEKTOR publication it was.