The MFJ-993B is an automatic antenna tuner for coax- or parallel wire fed antennas. Integrated is a SWR and power meter, a switch for two antennas and a 4:1 balun. Impedance matching range is 6 to 1600 Ω from 1.8 to 30MHz. 2000 memory locations store once found settings, speeding up the tuning process when a frequency is later used again. Tuning starts automatically when transmit power is applied, manual tuning is also possible.
An analog meter shows SWR, further a LC display shows SWR, power, frequency and other information. Very useful for visually handicapped users is the acoustic feedback on SWR. Max. power load is 300W PEP SSB, 150W CW
The optional interface cable MFJ-5124I allow connecting the tuner to any Icom rig with the 4 pin tuner socket (e.g. IC-706, IC-7456Pro, IC-756Pro/2/3 and many more). Over this cable the tuner is controlled and supplied with power.
Equipment by Kenwood and Yaesu are connected with the cables MFJ-5124K (Kenwood) and MFJ-5124Y (Yaesu). Since these rigs require a somewhat more complex control the cables include an electronics component which makes them more expansive.
The MFJ-993B is optionally supported by a remote control unit.