The 148A AM/FM/PM Generator gives you a one instrument source of modulated waveforms. It has two generators: a main function generator, with full function generator versatility, and a modulation generator, a convenient source for modulating and triggering waveforms or a second, independent signal source. 0.002 Hz to 20 MHz at up to 30 V p-p. Accuracy is ?(1% of the setting + 1% of full range) on the center settings and ?(2% of the setting + 2% of full range) for x.01-10 and x10 M.