The APVSG-X is a multi-output ultra-agile fast-switching vector-modulated signal source, covering a continuous frequency range with models ranging from 10 MHz to 4, 6, 12, 20 or 40 GHz. APVSG-X with 2, 3 or 4 channels is mounted in a 19‘‘ 2 HU enclosure. Each output can be programmed independantly in frequency, power, phase and modulation. The outputs are phase-coherent with excellent phase stability.