MFJ-998 Legal Limit IntelliTuner Automatic Antenna Tuner
Instruction Manual
©
2007-2010 MFJ Enterprises, Inc.
19
WARNING: Amplifier Bypass Control
TM
is a safety precaution; the tuner and amplifier are in
danger of being damaged if this function is turned off.
Meter Range Menu
Allows you to select the meter scale range. In the 300 watts (low) range, the forward full scale is 300
watts and the reflected full scale is 60 watts. In the 3000 watts (high) range, the forward full scale is 3000
watts and the reflected full scale is 600 watts (multiple the meter reading by 10). Auto range
automatically sets the meter scales according to the input RF power to the tuner. Forward power greater
than 300 watts or reflected power greater than 60 watts automatically sets the meter to the high power
range. Forward power less than 250 watts and reflected power less than 40 watts automatically set the
meter to the low power range. Refer to Figures 16 and 17 for the on-screen Meter Range indicators.
Default is AUTO Range.
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.
Memory Menu
Turns the antenna memory on and off. The “memory resolution” is the width of frequency spectrum that
the tuner recognizes as being the same as a tuned frequency already in memory. The memory resolution
is approximately 0.1 percent of the lower frequency of each amateur band. For example, the memory
resolution on the 40-meter band (7000 to 7300 kHz) is 7 kHz; if the tuner has memorized a setting for
7050 kHz, it will automatically call up this setting for any frequency from 7047 to 7053 kHz. Memory
resolution is smaller at lower frequency to accommodate the higher antenna Q and larger at higher
frequency where the antenna Q is lower. The memory resolutions for the HF amateur bands 160 through
10 meters are:
Meter
Frequency Range (kHz)
Memory Resolution (kHz)
160
1800 – 2000
2
75/80
3500 – 4000
4
60
5330.5, 5346.5, 5366.5, 5371.5 and 5403.5
5 memory locations
40
7000 – 7300
7
30
10100 – 10150
10
20
14000 – 14350
14
17
18068 – 18168
18
15
21000 – 21450
21
12
24890 – 24990
25
10
28000 – 29700
28
Table 1. Memory Resolution.
The memory resolution for non-amateur frequency bands between 160 and 10 meters is approximately
0.2 percent of the lower frequency of each band. There are over 2500 memory locations for each memory
bank, and each antenna has four memory banks (A-D). Tuner settings are stored in memory separately
for Antenna 1 and Antenna 2 (settings for single-wire antenna are stored as Antenna 1). This provides
memory for up to eight different antennas. Refer to Figures 16 and 17 for the on-screen Memory
indicator. Defaults are memory banks 1A and 2A ON.
