Here is a yig tuned GaAs Oscillator made by Avantek, P/N Y083-3669 removed from ECM/EW test equipment. This unit is a 2-4GHz type, so I swept it and found it makes good power from 2-4.4 GHz, >10 dBm, plotted this from my HP 8566B spectrum Analyzer, power is shown as 10 dB actually higher than shown due to cable loss not included. Comes with plot on which I have marked connections and voltage. Runs on +15 V DC. Unlike many other YTO's for sale on eBay, I test each one to make sure you do not get a dud!! Have fun.