MFJ-998 Legal Limit IntelliTuner Automatic Antenna Tuner Instruction Manual
© 2007-2010 MFJ Enterprises, Inc.
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Like all MFJ’s IntelliTuners
TM
, the MFJ-998 supports radio tuner interfaces that are compatible with
Alinco EDX-2 tuner, Icom AH-3 and AH-4 tuners, Kenwood AT-300 tuner, Yaesu FC-30 tuner, and
Yaesu FH-1 and FH-2 remote controls. Optional interface cables MFJ-5114A (for Alinco), MFJ-5114I
(for Icom), MFJ-5114K (for Kenwood), and MFJ-5114Y/Y3/Y4 (for Yaesu) are available from MFJ
Enterprises, Inc.
The MFJ-998 tuner enters a “sleep” mode when idle and when no transmit signal is present, turning off
the microprocessor clock to avoid the generation of spurious signals.
Features
• Automatically matches antennas from 12 to 1600 ohms impedance (SWR up to 32:1)
• Handles 1500 watts SSB/CW
• Tunes in less than 20 seconds, usually less than 5 seconds
• Amplifier Bypass Control
TM
automatically protects your amplifier during tuning and external high
SWR events
• Over 20,000 non-volatile memories for tuner settings
• Four memory banks per antenna with over 2500 memories per bank
• Highly efficient switched–L network matching circuit
• Direct read-out of matching L/C values available after tuning
• 1.8 to 30 MHz continuous frequency coverage
• Adjustable target SWR from 1.0 to 2.0
• Adjustable SWR threshold from 0.5 to 1.5
• Adjustable amp bypass SWR from 1.5 to 3.0
• Lighted cross-needle SWR/wattmeter with high, low, and auto range options
• Multifunction backlit LCD display with contrast control
• Numeric readings for SWR, forward and reflected power
• Bar meters for SWR, forward and reflected power with peak hold and range options
• Audio SWR meter
• Built-in frequency counter for remembering frequency-specific matching values
• Built-in radio interface circuitry for compatible radios
• Two SO-239 coax fed antenna connectors
• Connector for random wire or single wire antennas
• Field upgradeable firmware
Specifications
• Impedance matching range : 12 to 1600 ohms
• SWR matching range : Up to 4:1 for < 50 ohms and up to 32:1 for > 50 ohms
• Minimum power for tuning : 5 watts
• Maximum power while tuning : 100 watts with foldback, 20 watts without foldback
• RF power limit : 1500 watts SSB/CW
• Frequency range : 1.8 to 30 MHz continuous coverage
• Frequency counter accuracy : ±1 kHz across HF bands
• A/D conversion resolution : 10-bit
• Forward power display resolution : 0.1 for < 100 watts and 1 for ≥ 100 watts
• Reflected power display resolution : 0.1 for < 10 watts and 1 for ≥ 10 watts