The Series 690XXA Synthesized CW Generator and the Series 691XXA Synthesized Sweep Generator are microprocessor-based, synthesized signal sources with high resolution phase-lock capability. They generate both discrete CW frequencies and broad (full range) and narrow band sweeps across the frequency range of 10 MHz to 65 GHz. All functions of the 690XXA/691XXA are fully controllable locally from the front panel or remotely (except for power on/standby) via the IEEE- 488 General Purpose Interface Bus (GPIB). The Series 690XXA Synthesized CW Generator and the Series 691XXA Synthesized Sweep Generator each presently consists of 15 models covering a variety of frequency ranges and power levels.