"William Sommer******"

Some DMM user manuals suggest that you briefly short the diode while the
test leads are attached.


** Must be only prehistoric ones - I bet.

This forces the meter to downrange and give a
less-inaccurate reading of the forward resistance when the short is
removed.


** Neither manual nor auto-ranging DMMs have enough volts available on the
ohms ranges to forward bias a single silicon diode - let alone a series
string of them, as found in microwave oven diodes.

Most DMMs have " diode test " ranges fitted, which will supply up to a
couple of volts with a fixed current of about 1 mA. The reading is then in
volts or millivolts.



....... Phil