Self Supported

`4-Square for 80 / 75 M - Radial System`

Design by Eric Smitt K9ES

The feed and radial ring is fabricated with a piece of plumbing material (Copper coated steel strip) available from Lowes. The length purchased is 20 inches long, and it is cut in half to provide 2 metal strips. This piece has 5/8 inch holes and ¾ inch holes. Drill two 3/16 inch holes hear both ends for connection to the radial ring. Use a 5/8 hole to place a bulk head threaded double barrel UHF connector. This will be the coax attach point for the vertical. Place the barrel connector in place and secure with the supplied nuts that come with the bulkhead connector. Tighten down the nuts to assure a solid mechanical and electrical contact. On one end of the barrel, place a UHF – Banana Jack adapter. The PL259 coax feed will go on the other end.

Screw this plate (with bulkhead connector and the adapter facing the side where the aluminum pole is located) 1 inch above the ground dirt.Wrap a #6 AWG solid piece of copper wire (about 40 inches long) through the two 3/16 inch holes to form a ring approximately 9 inches in diameter. Secure the ring with a small piece of 18 AWG bare copper wire, such that the excess end extends away from the support pole (this will connect to the ground rod). Solder the splice and then solder the ring to the copper plate. This completes the radial ring assembly.

Drill a 1/8 inch hole near the very bottom of the aluminum pole, and attach a 16 inch piece of #14 AWG solid copper wire between this hole and the Tuning Stub. The other wire from the tuning stub goes to the UHF – Banana Jack adapter. This wire becomes part of the antenna length. I used a stainless steel machine screw, 8 x 32 ¾ inch long, with a lock washer and 3-32 stainless nut, and then fastened the wire to the aluminum pole with a #8 wing nut and #8 washers.

I found a source of insulated #18 AWG wire in 1000 foot rolls. The easiest method for cutting these to ¼ wave length was to wrap them around 2 antenna posts, and walk back and forth. After running around 7 times, I managed to get 14 radials measured. Once the spool of wire was depleted, I cut them from each pole, and produced 14 radials per antenna. One end was stripped and wrapped and secured around the radial ring, and the other end was laid on the ground in as symmetrical a pattern as I could achieve.

How many radials are required? This is a very subjective methodology. Some people provide hundreds of radials per vertical. With my water table at 1 foot below surface, 14 radials seemed to work.

The radials are all held to the ground using 3 inch staples, purchased from Tractor Supply Company. These staples are used in the installation of electric fencing, and are quite inexpensive. I actually placed a staple every 6 feet on each and every radial, hammering it into the ground. The grass grows over the radial and one is able to mow the lawn without fear of grabbing a radial. After about 2 months of growth and cutting, the radials are pretty much hidden.

*Basic Information*	*The Pivot Support*	*DX-Spyder Fiberglass & Vertical*
*Loading Coil*	*Tuning Stub*	*Radial Ring*
*Phasing Lines*	*Tuning*	*Comtek Controller*

Pulley System

Performance

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