The Agilent 53181A RF counter provides fast, precise results with the core measurements needed for RF tests. It measures frequency, frequency ratio (with the optional 2 channel), period and peak voltage with 10 digits/second resolution. The Agilent 53181A offers a single 225 MHz channel standard, and you can choose an optional second channel that measures up to 1.5 GHz, 3 GHz, 5 GHz or 12.4 GHz.