MFJ-993 IntelliTuner Automatic Antenna Tuner
Instruction Manual
©
2003-2004 MFJ Enterprises, Inc.
15
The memory resolution for non-amateur frequency bands between 160 and 10 meters is approximately
one percent of the lower frequency of that band. There are over a thousand memory locations for each
antenna. Tuner settings are stored in memory separately for Antenna 1 and Antenna 2 (settings for
balanced line or single-wire antennas are stored as Antenna 1). Refer to Figure 10 for the on-screen
Memory indicator. Default is ON.
To clear the memory for one antenna, select the antenna with the [ANT] button, turn off the power to the
tuner, then press and hold both [TUNE] and [C-DN] buttons while turning on the power. A
DELETE
ANTENNA
message will appear. “Total Reset” erases both antenna memories and returns all tuner
settings to their factory default states. To achieve this, turn power off, press and hold [TUNE], [L-DN]
and [C-DN] buttons while turning on the power. A
TOTAL RESET
message will appear.
IntelliTune Menu
Turns the IntelliTune
TM
tuning algorithm on and off. When
the
tuner cannot find an appropriate setting in
its memory, it begins its calculation function. It measures the complex impedance of the antenna (load) at
that frequency, then it calculates the L/C components needed for a match. Then it fine-tunes the
component values. If for any reason the tuner cannot calculate the load impedance, it proceeds to yet
another method of calculation. If for any reason, this function can be turned off. Refer to Figure 10 for
the on-screen IntelliTune
TM
indicator. Default is ON.
SWR Beep Menu
Turns the aural SWR meter on and off. The aural meter is a series of one to five beeps where one beep
indicates SWR of 1.5 or less, two beeps indicate SWR of 1.6 to 2.0, three beeps indicate SWR of 2.1 to
2.5, four beeps indicate SWR of 2.6 to 3.0, and five beeps indicate SWR above 3.0. This functions
independent of the acknowledgement beep setting. When ON, a musical note
♪
appears on the lower
right corner of the main menus (refer to Figure 10). Default is OFF.
Shortcut:
Press both [L-UP] and [L-DN] buttons simultaneously to toggle SWR Beep on and off.
Beep Menu
Acknowledgement beep sounds each time a parameter is changed to acknowledge it. This function can
be turned OFF for silent operation, and this is independent of the SWR beep setting. Default is ON.
Peak Hold Menu
When the peak hold function is ON, the highest activated segment of the forward bar meter remains
visible for about one second, so that you can more easily read it. When OFF, the meter functions
normally. Default is ON.
Refresh Menu
When the refresh function is ON, the display is updated while tuning is in progress. Default is OFF.
Note:
Refresh slows tuning progress as it takes time to update the display.
LC Limit Menu
The upper limits of inductance (L) and capacitance (C) are factory-limited according to frequency and
maximum power rating; i.e., higher frequencies need less inductance and less capacitance when the L-
network is properly tuned. Pressing [C-UP] and/or [L-UP] allows capacitance and inductance to be
Summary of Contents for MFJ-993
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