MFJ-5124K/Y Radio Interface
Instruction Manual
©
2005 MFJ Enterprises, Inc.
3
Connections
1. Insert the 3.5 mm stereo phone plug into the tuner’s RADIO
INTERFACE jack.
2. Insert the 2.1 x 5.5 mm coaxial power plug into the tuner’s POWER
jack.
3. Insert the 8-pin modular plug into the MFJ-5124’s TO RADIO jack.
4. Important:
Make sure the DC power to the radio has been turned off.
The radio does not fuse the DC power to the tuner, and damage to the
radio can occur if the interface’s power connection comes in contact
with ground.
5. Connect the 6-pin molex connector to the mating 6-pin molex
connector, marked as AT or ACC, on the back of the Kenwood radio.
6. Push the [POWER] button on the tuner to the
in
position. When the
radio is powered on, the tuner will also power on.
7. Some Kenwood radios automatically check to see if an external
antenna tuner is connected during power on, such as the TS-570S (set
jumper JP2 to the A position). This is the factory default setting. If
both needles on the MFJ tuner keep bouncing (
TURN ON RADIO
appears on the MFJ-993) and do not go away, then move jumper JP2 to
the B position.
For other Kenwood radios, the External Antenna Tuner menu in the
radio menu system must be enabled, such as the TS-450S and the TS-
690S (set jumper JP2 to the B position). If the MFJ tuner switches to
bypass mode during power on, then move jumper JP2 to the A position
because the radio is checking for a tuner presence during power on.
Refer to your radio’s operating manual for accessing the menu system
and preparing the AT-300 operation.
Operation
The operation of the MFJ-5124K radio interface is similar to the operation of the
AT-300 described in the Kenwood radio user’s manual. Press and hold the [AT
TUNE] button on the radio for one second to start the tuning process. The radio
will automatically switch to CW mode, transmit a 10-watt carrier, and start the
tuning process. When the tuning process is completed, the radio will stop
transmitting, return to its previous mode and power setting. Press the [AT
TUNE] button on the radio briefly will place the tuner into bypass mode (some
Kenwood radios, such as the TS-690S, do not have this bypass function).
Note the [TUNE] button on the tuner will not operate the radio interface.
