0 pins are on the high power RF circuit board.Input RF type Switch, SPDT of the Evaluation board.Using the HMC546 search parameter, you can discover variants of the RF Board.PCB is the one that mounts RF Board.
115203-HMC546LP2 Features
0 pins Switch, SPDT Type
115203-HMC546LP2 Applications
There are a lot of Analog Devices Inc. 115203-HMC546LP2 RF Boards applications.