0 pins are on the high power RF circuit board.Input RF type Mixer of the Evaluation board.Using the HMC686 search parameter, you can discover variants of the RF Board.PCB is the one that mounts RF Board.
125658-HMC686LP4E Features
0 pins Mixer Type
125658-HMC686LP4E Applications
There are a lot of Analog Devices Inc. 125658-HMC686LP4E RF Boards applications.