The CMC250 1.3 GHz Multifunction Counter measures frequency of sine,square and triangle waves from 5 Hz to 1.3 MGz.
The CMC250 also provides period measurements and totalize functions. Channel A is a standard 1 Mohm input for frequency measurements up to 100 MHz. Channel B is a special 50 Ohm terminated input, prescaled to 1.3 MHz for easy RF measurements. The time stability is +- 10 ppm/yr.