Frequency-, Counter, Speedometer Frequency-, Counter, Speedometer EA 6110-FA 4digit Frequencycounter/Speedometer, prog. time base, 2 MHz, 13-50mm EA 6110-PA 4digit measures lenght of pulses, prog. time base, 13-50 mm EA 6533 8/16 digit Frequency/Pulsewidth counter with RS-232, 40MHz, Autorange