MFJ-998 Legal Limit IntelliTuner Automatic Antenna Tuner
Instruction Manual
©
2007-2010 MFJ Enterprises, Inc.
18
Setup Mode Menus
The setup mode menus allow you to customize how the MFJ-998 tuner operates. There are 13 setup
mode menus arranged in a “wrap-around” structure. To access these setup menus, press and hold the
[MODE] button for two seconds. The setup menu that will display is the one that was last used. When
finished, press the [MODE] button for two seconds to go back to the main mode for normal operation.
The tuner goes into protective bypass mode in the setup mode and restores the matching network after
exiting the setup mode. If no button is pressed for more than eight seconds, the tuner automatically exits
the setup mode, restores the matching network, and returns to the main mode.
To access the LC Limit setup menu from any setup menu, press and hold the [MODE] button and within
two seconds press both [C-UP] and [L-UP] buttons. This difficulty is built-in so the LC Limit is not
accidentally disabled. Notice the LC Limit is not saved into non-volatile memory and will revert back to
default ON when power is turned off. In addition, the following setup modes are stored separately for
antennas 1 and 2: Target SWR, Auto Tune SWR, Amp Bypass SWR, Meter Range, Peak Hold, Memory,
and
IntelliTune
TM
.
Within each setup menu:
•
Press the [MODE] button briefly to cycle forward through the setup menus. Press and hold the
[MODE] button for two seconds to exit the setup mode and go back to the main mode.
•
Press the [ANT] button to cycle backward through the setup menus.
•
Press the [C-UP] or [L-UP] button to increase or turn on the setting for the current setup menu.
•
Press the [C-DN] or [L-DN] button to decrease or turn off the setting for the current setup menu.
Target SWR Menu
Allows you to set the target SWR from 1.0 to 2.0. The tuning process will stop when a match with an
SWR less than or equal to the target SWR is found. Setting the target SWR lower than 1.5 may result in
longer tuning times. The target SWR is shown on the initial display when the tuner is powered on.
Default is 1.5.
Auto Tune SWR Menu
Allows you to set the SWR threshold
in the range 0.5 to 1.5. In the automatic mode, the tuning process
will automatically start when the SWR is above the target SWR by this amount of SWR threshold. For
example, for target SWR of 1.5 and auto tune SWR of 0.5, the tuning process will start whenever the
SWR rises above 2.0 (1.5 + 0.5) and there is at least five watts of RF power applied. The AMP BYPASS
feature of the MFJ-998
MUST
be used when implementing Auto-Tune to prevent tuning under high
power conditions. Default is 0.5.
Amp Bypass SWR Menu
Allows you to set the amplifier bypass SWR from 1.5 to 3.0. The amplifier connected to the Amp Enable
connection will be bypassed when the SWR is above the amp bypass SWR. Default is 2.0.
Note: Pressing [MODE], [L-UP] and [L-DN] simultaneously toggles the Amplifier Bypass
Control
TM
feature ON and OFF; and disables the StickyTune
TM
mode, if enabled. Refer to
Figures 16 and 17 for the on-screen Amp Relay Enable indicator. If this feature is turned
OFF (not recommended), it will be re-set to ON whenever power is cycled.
