The HP 33120A uses digital synthesis to produce a full featured DC to 15MHz waveform in arbitrary form. The device offers both linear and log swept, internal AM, FM, FSK and burst modulation. Output impedance is 50Ω and runs from 0 to 10Vpk-to-pk. Control is either front panel, HP-IB or RS-232. Bus control can also be used to program the waveform of the instrument for various applications.