This class AB GaN solid-state power amplifier supports spacecraft payload downlinks, Earth-observation downlinks and inter-satellite links. Output is specified against modulation rather than saturation alone: 33 dBm minimum at 64QAM over 20 MHz with -27 dB EVM, 37 dBm minimum at BPSK with -7 dB EVM, and 43 dBm typical saturated on a CW sweep. Gain flatness is 2 dB peak to peak. Protection is comprehensive for this class, with over, under and reverse voltage protection, over-temperature protection tripping at 85 °C, a temperature monitor output pin and RF output open-load survivability at 42 dBm CW. Supply is a wide 12 to 30 VDC drawing 2.1 A typical at 64QAM and 2.7 A at BPSK at 28 VDC, with 0.63 A idle. Interfaces are SMA female on RF input and output, cooled by baseplate conduction. The enclosure is 152 x 64 x 28 mm (6 x 2.5 x 1.1 in) at 482 g, IP54 rated, -40 to +85 °C operating and -55 to +85 °C storage, designed to comply with MIL-STD-810 vibration test methods. Typical lead time for standard configurations is 8 to 10 weeks.