40 meter Off-Center-Fed Dipole

Created Thursday 07 March 2024

To launch the 2024 new station, I wanted a versatile multi-band antenna. I settled on an off-center-fed dipole (OCF) accompanied by an antenna tuner. The OCF dipole feed point works well for the layout of the back yard. I don't have an acre to work with as I did in the 70s. My guide for this antenna was an article by Dick Sander, K5QY. I terminated the 450 ohm ladder line with a 9:1 balun at the outside wall of the house. From that termination, coax is used to feed the MFJ antenna tuner.

Back at building antennas! The steel structure for the deck arbor provided a great base for a mast. The total height is 30 feet. The mast is fifteen feet of 1-1/2 PVC conduit. To secure the base of the mast, I bolted a trailer jack footplate to the steel structure. Given the extent of my welding experience, that was a great solution that proved to be economical.

Just admiring my handiwork. That's pretty tall!

Visible are the guy lines and transmission line. Not visible is the actual antenna wire at the top of the mast. The short end of the dipole is secured to a line that I threw over the shop building to the left. The long end is tied off to a 15' mast in the garden area to the right.

With the installation of a 20 meter vertical in the place of the mast, this antenna is no longer in service.