Benchtop Timer/Counter. A broadband continuously variable, x100, analog attenuator lets you add just enough attenuation to minimize the input signal noise level and optimize the signal amplitude for counting. A switching 100 kHz, lowpass filter solves the problem of high frequency contamination of audio signals. Frequency measurement: Range - 5 Hz to 80 MHz, ac coupled. Resolution: 0.1 Hz to 10 kHz in decade steps. Accuracy: +/-1 count +/- time base error.