The Philips PM 6654 is a programmable, high resolution Timer / Counter with 2 ns single pulse resolution. Frequency and period can be measured with high accuracy with 9 digits resolution in one second. Inputs A and B have a frequency range of DC to 120 MHz, channel C is a high-sensitivity 1,5 GHz input with wide 10 mV to 12 V dynamic range. Time interval resolution down to 0,5 ps averaged and 2 ns single-shot. Measuring modes include phase, rise/fall time, duty factor, and various others. 8 pre-programmable front-panel menus. Digital readout of trigger levels, trigger facilities include arming, hold-off, external gating, and auto trigger level. Several mathematical functions.