This document is an instruction manual from MFJ Enterprises, Inc., providing information on the features and specifications of the MFJ-998 IntelliTuner Automatic Antenna Tuner. The tuner has a fast start feature and a front panel with SWR/Wattmeter, LCD display, and various buttons. The back panel includes Amp Enable In and Amp Enable Out interfaces.
The MFJ-998 IntelliTuner is a full‑legal‑limit automatic antenna tuner with an internal SWR/wattmeter, amplifier bypass control, and up to 20,000 non‑volatile memory slots. It covers 1.8‑30 MHz, handles up to 1500 W SSB/CW, and matches impedances from 12 Ω to 1600 Ω.
The manual includes safety notices, installation instructions, front‑ and back‑panel descriptions, menu navigation, radio interface connections for major brands, calibration procedures, and warranty information.
| Impedance matching range | 12 to 1600 ohms |
|---|---|
| SWR matching range | Up to 4:1 for < 50 Ω, up to 32:1 for > 50 Ω |
| Minimum power for tuning | 5 watts |
| Maximum power while tuning | 100 W with foldback, 20 W without foldback |
| RF power limit | 1500 watts SSB/CW |
| Frequency coverage | 1.8 MHz to 30 MHz continuous |
| Frequency counter accuracy | ±1 kHz across HF bands |
| A/D conversion resolution | 10‑bit |
| Forward power display resolution | 0.1 W (< 100 W), 1 W (≥ 100 W) |
| Reflected power display resolution | 0.1 W (< 10 W), 1 W (≥ 10 W) |
It matches impedances from 12 ohms up to 1600 ohms.
The tuner is rated for up to 1500 watts SSB/CW.
The tuner can start tuning with as little as 5 watts.
It offers over 20,000 non‑volatile memories, with four banks per antenna and more than 2,500 memories per bank.