spec - yeah the readings for the electret experiment are for alternating volts. also the half volt reading was the uppermost reading ive seen but its generally reading approx 10mV constantly.
when the leads are shorted the readings drops to 0V
followup - the half volt reading could be a meter calibration issue or something like that. the upper most reading on the lowest ac setting (2) is .05v but with the next setting (20) the reading remains the same but the decimal place has shifted giving the half volt reading