milliohmmeter - a 'magnifier' for small resistances

milliohmmeter With many of the digital multimeters used nowadays, the measuring of very small resistances in the milliohm range presents certain problems. With a "full scale deflection" of 199.9 E2, the display error after the decimal point can be 100%! This certainly leaves a lot to be desired. For this reason, a more precise method must be applied when measuring the resistances of loudspeakers, coils, conductors (printed circuit board copper tracks) and the like. The lowest measuring range of the milliohmmeter is 0.5 E2 ±1% (full scale deflection), which gives us something to work with. Let us assume that our digital multimeter has a lowest measuring range of 199.9 E2 ±1% 1 deviation from the displayed value; the percentage with a displayed value of 0.1 E-2 can be discounted, but the specified precis- ion of ±1 digit means that the value read off can be 0.0 or 0.3 E2. This corresponds to an inaccuracy of 100% and becomes unacceptable. Moreover, if one takes into account the c...