Additional Features: Measures AM and FM to 1% accuracy Adjacent-channel power measurement capability Measures RF power with power meter accuracy Audio measurement capabilities The Agilent 8901B, Modulation Analyzer determines RF frequency and measures RF power. The major additional capabilities of the Agilent 8901B, Modulation Analyzer, are its improved power-meter accuracy, its ability to make adjacent-channel power measurements or carrier-noise measurements (with Options 030 through 037), and its ability to count audio frequencies and measure distortion on 400 Hz and 1 kHz signals.