MFJ MFJ-974, Instruction Manual, Page: 7 / 10

MFJ-974/974H Balanced Line Antenna Tuner Instruction Manual
7
Technical Assistance
If you have any problem with this unit first check the appropriate section of this manual. If the manual does not
reference your problem or your problem is not solved by reading the manual, you may call
MFJ Technical Service
at 662-323-0549 or the MFJ Factory at 662-323-5869 . You will be best helped if you have your unit, manual and
all information on your station handy so you can answer any questions the technicians may ask.
You can also send questions by mail to MFJ Enterprises, INC., 300 Industrial Park Road, Starkville, MS 39759;
by Facsimile (FAX) to 662-323-6551; or by email to techinfo@mfjenterprises.com. Send a complete description
of your problem, an explanation of exactly how you are using your unit, and a complete description of your
station.
WARNING!
To avoid problems, a dipole antenna should be a full half-wavelength on the lowest
band. On 160 Meters, an 80- or 40-Meter antenna fed the normal way will be
extremely reactive, with only a few ohms of feedpoint resistance. Trying to load an
80-Meter halfwave dipole (or shorter) antenna on 160 Meters can be a disaster for
both your signal and the tuner. The best way to operate 160 Meters with an 80- or
40-Meter antenna is to load either or both feedline wires (in parallel) as a longwire.
The antenna will act like a “T” antenna worked against station ground.