MFJ-9420 Installation Manual
20-Meter SSB Travel Radio
SIMPLE 20-METER ANTENNA SUGGESTIONS
COAXIAL FED DIPOLES: A wire dipole for the phone band should measure about 32'10"
(16'5" per leg). Feed with RG-58U or RG-8X; raise high and in the clear for best performance.
If you have only one high support, make an inverted V. The "full sloper" (sloping dipole) is also
an excellent single support antenna with some directivity.
>90
Best
Direction
Support
34’ 4”
DIPOLE
INVERTED V
FULL SLOPER
MFJ-1772 PORTABLE DIPOLE: As an alternative to making a coax-fed dipole, consider
purchasing the pre assembled MFJ-1772 antenna. This is a no compromise 20-Meter folded
dipole complete with 30' of feedline all made from ultra lightweight 300 Ohm twinlead. Connect
a random length of coax from the MFJ-1772 feedline to your rig and let the antenna's built in 50
Ohm matching network do the rest. The antenna is pre tuned, easy to handle, and sufficiently
broad banded to cover both the CW and phone band.
3.0
2.0
1.5
1.0
SWR
FREQ
14.0
14.1
14.2
14.3
Flat Top
End-line
Balanced
Feeder
50-Ohm
Coax
TYPICAL SWR CURVE
MFJ 1772 DIPOLE
WARNING: CONSTRUCTING OR ERECTING AMATEUR RADIO ANTENNAS IN
LOCATIONS WHERE THEY MAY COME INTO CONTACT WITH
ELECTRICAL POWERLINES MAY RESULT IN ACCIDENTAL
INJURY OR DEATH!
