Installation - MFJ -926B Instruction Manual

MFJ-926B HF Automatic Remote Antenna Tuner

Installation

● Never operate the tuner with its cover removed. Contact with the components inside the
tuner while transmitting will result in painful RF burns.
● Locate the tuner so that the terminals are not accessible during operation. The single wire
connection may have high voltage while transmitting.
● Disconnect all antennas from the tuner during lightning storms.
● Always tune with low power (2-10 watts). Apply maximum power only after tuning up.
● Never exceed tuner specifications.
● Do not transmit with a high SWR for extended periods of time.
1. Place the tuner in a convenient location at the operating position using the mounting holes provided.
With a random wire, the WIRE terminal may have high RF voltages present. These voltages can
cause serious RF burns if the terminal is touched when transmitting. Be sure to locate the tuner so
this terminal cannot accidentally be contacted during operation.
2. Install the MFJ-4117 Bias-Tee between the transmitter and the antenna. Use a 50-ohm coaxial cable
(such as RG-58) to connect the transmitter. See Figure 1.
3. Connect the transmitter to the "RF IN/OUT" coaxial connector on the MFJ-4117 Bias-Tee using a
50-ohm coaxial cable. (See Figure 1) This is the RF signal input connector.
4. Connect a 12-15 VDC voltage source capable of supplying at least 750 milli-amps to the "DC
IN\OUT" jack on the MFJ-4117 Bias-Tee. This is your DC voltage input connector.
5. Connect the "RF/DC OUT/IN" coaxial connector on the MFJ-4117 Bias-Tee to the
TRANSMITTER connector on the MFJ-926B Intellituner using 50-ohm coaxial cable. The MFJ-
926B Intellituner will recover the RF and DC signals.
6. Connect your coax-fed antenna to the ANTENNA connector using a 50-ohm coaxial cable, or
connect your random wire to the WIRE binding post.
7. Connect your ground connection to the GROUND post.
8. Key your transmitter to output a carrier of 2-10 watts CW, FM or AM. If desired, an external
SWR/Wattmeter can be used to verify a tuned SWR of 1.5 or less before increasing RF power.
9. You are ready to transmit.
If too much power is applied when tuning, tuning will cease and the tuner will go into the bypass
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mode. This occurs when the forward power exceeds 75 watts and the SWR is greater than 3.0, or
when the forward power exceeds 125 watts regardless of the SWR.
If more than 200 watts is applied to the tuner, the tuner will go into bypass mode.
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Random wire and coax antennas must not be connected simultaneously to the WIRE and coax
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connectors on the tuner.
Note: Route all random wire antennas safely to prevent RF burn hazard.
© 2010 MFJ Enterprises, Inc.
WARNING
Instruction Manual
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