This RF adapter bit is great for anyone doing RF work. Depending on the dev-board and antenna you have, you may be faced with either RP-SMA or SMA connectors. Unfortunately they are not compatible! This adapter solves the problem with an SMA jack on one end and an RP-SMA Plug on the other.
Check your cable, connector and antenna to verify whether you need this adapter, or . In specific, look for the center contact, is it an 'innie' or an 'outie'? This adapter is likely best used for connecting an SMA antenna to a board with an RP-SMA connector