I have a middle of the road DMM (Greenlee model 93-606), no RS-232 or=20
auto ranging that the AC & DC volt readings are in error (low at the=20
moment, but could have been high previously) by as much as 20%. I have=20
cleaned all the contacts, reflowed some of the through the hole soldered=20
joints, and cleaned the volt adjusting pot with tuner cleaner/lubricant.=20
The rotary selector switch contacts have been cleaned and look good=20
condition. The battery is fresh recharge 9 volt NI-mh. There doesn't=20
appear to be any change in reading when tapping the board or components.=20
The pot seems stable with no jumps in readings through the full range.=20
Several days ago, I reassembled the meter after calibrating the=20
voltages. After reassembling the voltages looked good, and then today=20
went to check some fresh charged batteries and the readings were 16%=20
compared to a meter believed fairly accurate. Both meters were checked=20
recently using a PC power supply with intel's active monitor. May not be=20
a super reference, but best I've got. Resistance readings seem close for=20
lower resistances (< 5k), and a little low for the higher resistances=20
(>500k). Theses readings seem stable after numerous on/off cycles and=20
range changes.

Any thoughts would be appreciated. This was a mid priced meter, like=20
it's feel, and would rather not invest in a replacement at this time. I=20
do have an auto ranging RS-232 meter also.
--=20
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