MFJ-926B HF Automatic Remote Antenna Tuner
Instruction Manual
2010 MFJ Enterprises, Inc.
6
Installation
WARNING
●
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
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.
•
Random wire and coax antennas must not be connected simultaneously to the WIRE and coax
connectors on the tuner.
Note:
Route all random wire antennas safely to prevent RF burn hazard.