Gunn-diode oscillator model SOF-2820-M1 tunes mechanically from 29.5 to 37.5 GHz. Typical output power is +18 dBm. Featuring a WR-28 waveguide output port and a female SMA bias-voltage input port, the oscillator requires +5 VDC at 850 mA. A micrometer tuner enables repeatable and stable frequency adjustment.  https://www.eravant.com/33-5-ghz-4-ghz-tuning-18-dbm-output-pwr-wr-28-wg-ka-band-wide-mech-tuning-bandwidth-gunn-oscillator