MODEL 15P SM-114 test instrument is a compact 3-function test meter designed to indicate the condition of any 52 ohm antenna and antenna coax used for Citizens Band radio operation by testing for Standing Wave Ratio, relative RF power, or field strength. Tuning of transmitters can also be accomplished when using this meter as a field strength meter. Also, comparing antennas can be accomplished with this meter. It is designed to be used for base stations or mobile operations and can be permanently installed in the antenna system without any measurable loss of power.