Note
The MFJ-929 Compact IntelliTuner is an automatic antenna tuning center designed to rapidly match unbalanced or single-wire antennas. It functions as a comprehensive station accessory, combining an automatic tuner, an SWR/wattmeter, and a two-position antenna switch into a single unit.
– Power Rating: It is rated for a maximum throughput of 200 watts SSB/CW.
– Frequency Range: Continuous coverage from 1.8 to 30 MHz across the HF bands.
– Impedance Matching Range: Automatically matches impedances from 6 to 1600 ohms. This translates to handling an SWR of up to 8:1 for loads under 50 ohms, and up to 32:1 for loads above 50 ohms.
– Tuning Network: It employs a highly efficient, digitally switched L-network configuration. It features 256 discrete values of capacitance (0 to 3961 pF nominal) and 256 values of inductance (0 to 24.86 µH nominal). Because the capacitance can be dynamically switched between the input (transmitter) and output (antenna) side, it yields a total of 131,072 L/C tuning combinations.
– Relay Specs: Built with heavy-duty 10-amp / 1000-volt relays to handle the high RF voltages and currents generated during operation.
The MFJ-929 relies on three integrated proprietary learning algorithms to accelerate tuning times:
– InstantRecall: When you key the radio, the tuner instantly cross-references its memory banks. If you have operated on or near that frequency before, it restores the match in milliseconds.
– IntelliTune: If a new frequency is detected, this system measures the complex impedance of the antenna and calculates the necessary L/C values to instantly snap them into place before executing fine-tuning adjustments.
– Adaptive Search™: If the antenna's complex impedance sits outside the initial measurement range, the tuner measures the exact frequency and executes targeted search patterns to locate a match quickly.
Memory Capacity: It boasts over 20,000 non-volatile virtual memories. Each of the two antenna selections features four separate memory banks (A, B, C, and D), with each bank storing more than 2,500 individual frequency matching solutions. The data retention of this non-volatile memory is rated for over 200 years.
Tuning Thresholds: It requires a minimum of 2 watts to initiate a tune , with optimal tuning accuracy occurring between 10 and 20 watts. Users can adjust the target tuned SWR anywhere from 1.0 to 2.0.
The front panel includes a 2-line by 16-character backlit LCD display with an external contrast adjustment trimpot. It provides simultaneous digital readouts for SWR, forward power, and reflected power, alongside dual 60-segment power and 36-segment SWR analog bar-graph meters.
Features
– Automatically matches antennas from 6 to 1600 ohms impedance (SWR up to 32:1)
– Handles 200 watts SSB/CW
– Tune in less than 15 seconds, usually less than 5 seconds
– Over 20,000 non-volatile memories for tuner settings
– Four memory banks per antenna with over 2500 memories per bank
– Highly efficient switching L-network matching circuit
– 1.8 to 30 MHz continuous frequency coverage
– Adjustable target SWR 1.0 to 2.0
– Adjustable SWR threshold 0.5 to 1.5
– Multifunction backlit LCD display with contrast control
– Numeric readings for SWR, forward and reflected power
– Bar meters for SWR, forward and reflected power with range options
– Audio SWR meter
– Built-in frequency counter for remembering frequency-specific matching values
– Built-in radio interface circuitry for compatible radios
– Built-in bias tee
Specifications
– Impedance matching range : 6 to 1600 ohms
– SWR matching range : Up to 8:1 for < 50 ohms and up to 32:1 for > 50 ohms
– Minimum power for tuning : 2 watts
– Maximum power while tuning : 100 watts with foldback, 20 watts without foldback
– RF power limit : 200 watts SSB/CW
– Frequency range : 1.8 to 30 MHz continuous coverage
– Frequency counter accuracy : ±1 kHz across HF bands
– A/D conversion resolution : 8-bit
– Power display resolution : 0.1 for < 10 watts and 1 for $\ge10$ watts
– SWR display resolution : 0.1
– Power bar meters resolution : 60 segments
– SWR bar meter resolution : 36 segments
– Capacitance range : 0 to 3961 pF nominal (256 values)
– Inductance range : 0 to 24.86 μΗ nominal (256 values)
– Relay rating : 10 amp 1000 volts
– Relay electrical life : 100,000 operations
– Relay mechanical life : 10 million operations
– Memory endurance : 1 million erase/write cycles
– Memory data retention : > 200 years
Power Requirements: Operates on 12–15 VDC and draws a maximum current consumption of 850 mA or less. It includes an automatic "sleep mode" that shuts down the microprocessor clock when the unit is idle to prevent any local RFI/spurious emissions.
