Sound Level Meter LSDM-A11 is a universal sound level meter that measures the exponential time weighted sound level. It is small in size, light in weight and easy to carry unit. It has 1/2 inch electret condenser type microphone and offers 4 measurement parameters Lp (sound level), Leq (Equivalent Continuous A Sound Level ), Lmax ( Maximum Sound Level) and LN (Percent of all readings over alarm value set with 4 digit LCD display, function mark, time weighting, weighting icon and data memorized. Permits choice ‘A’, ‘C’ , ‘F’ weighting and ‘Fast’ / ‘Slow’ response times and interface use RS-232 data output to connect with PC.