The FD-252 digital frequency counter is designed for applications that require a high frequency range. The instrument is equipped with, in addition to the 20 Hz-160 MHz input, a second input for measurement up to 2.4 GHz with an impedance of 50 Ohms.

It has an excellent frequency sensitivity and three selectable gate time fixed values, thus letting the user obtain an optimum ratio between the measurement time and the resolution. It also has a selectable band-pass filter at Input A, thus allowing the measurment of low-frequency signals without interference.

A time base option (TCXO) is available.