MFJ-939 Plug&Play IntelliTuner Automatic Antenna Tuner
Instruction Manual
2006-2015 MFJ Enterprises, Inc.
9
OPERATION
MFJ-939I Icom
IC-706, IC-707, IC-718, IC-725, IC-728, IC-736, IC-738, IC-746, IC-756, IC-7000
Operation
The operation of the MFJ-939I tuner is similar to the operation of the AH-3 or AH-4 described in the
Icom radio’s operating manual.
1.
Push and hold the [TUNER] button on the radio for one or two seconds to initiate automatic
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.
2.
Push the [TUNER] button on the radio quickly to bypass the tuner or to cancel tuning in progress.
Note the [TUNE] button on the tuner will also key the Icom radio interface.
Icom Radio Interface
The MFJ-5114I radio interface allows users of AH-3 or AH-4 compatible Icom transceivers to connect to
the MFJ-939
Plug&Play IntelliTuner
™ Automatic Antenna Tuner. With this interface, control signals are
connected between the radio and the tuner. The operator can then control the tuner with a single push of
the [TUNER] button on the front panel of the radio. Supported Icom radios are IC-706, IC-707, IC-718,
IC-725, IC-728, IC-736, IC-738, IC-746, IC-756, IC-7000, and any Icom radio that supports the Icom
AH-3 or AH-4 tuner.
Connections
Jumper
Setting
JP2
I
JP4
REMOVE
CABLE MFJ-5114I
Table 1
Icom
The MFJ-5114I interface cable provides control signals between an Icom radio and the MFJ automatic
tuner. Supported Icom radios are IC-706, IC-707, IC-718, IC-725, IC-728, IC-736, IC-738, IC-746, IC-
756, IC-7000, and any Icom radio that supports the Icom AH-3 or AH-4 tuner. Push and hold the radio’s
[TUNER] button for two seconds to start the tuning process. Push [TUNER] quickly to bypass the tuner.
Make sure jumper JP4 is removed for IC-7000
Pin (Key) connects to pin 6 of Radio Interface Plu
Pin (Start) connects to pin 8 of Radio Interface Plug.
Pin (Ground) connects to pins 4 and of Radio Interface Plug.
2
Pin 3 (+13.8V) connects to pins 2 and 3 of Radio Interface Plug.
4
5
1
g.
1
2
3
4
Figure 7 Icom Interface Cable.