Vertical Base Replacement Coil

If you currently have the Hy-Gain AV-18VS, you know how difficult it is to change the resonant frequency with the stock coil. Our coil coupler slides up and down the coil for easy matching.

Use our coil as a replacement coil for the Hy-Gain or other base vertical antennas using a tapped coil. Replace the stock coil with our variable replacement coil. It is easier to tune. There are no coil clamps to screw.

It may be used at power levels up to 300 Watts SSB, 150 Watts CW and 80 Watts with digital modes.

The coil cores are machine grooved to allow evenly spaced and secure placement of the coil wire. We shaved off 1/64" of the PVC tubing. This is just enough of a cut for the wire placement without degrading the integrity of the PVC tubing for antenna use.

This spacing of the coil winding allows a more selective tuning and lower SWR, as well as keeping the wire secure when sliding the tuning coupler up and down the core.

The coil wire is made of heavy duty corrosive resistant stainless steel wire. The tuning coupler is made of a heavy gauge stainless steel pick up clip, tapped and threaded. The coupler body is also tapped and threaded. Stainless steel machine screw and steel nut are used to secure the pick up clip and shorting wire to the coupler.

Using all stainless reduces the chance of corrosion and the heady gauge stainless steel clip will not deform or come loose during use as soft copper or brass will.

Each coil has been tested prior to shipping.

Overall dimension 9 inches x 1.5 inches. Coil is 1 3/8 by 5 inches on a 9 inch long core.

To tune your coil, simply slide the tuning coupler up and down the coil until maximum noise or signal is received. Or, if you are using an antenna analyzer, slide the tuning coupler up and down until low SWR is achieved. You may need a slight twist the coupler to get an even lower SWR.

Installation is simple. Remove the stock coil, taking note of where the feed clamp is located. Attached the Wolf River Vertical Base Replacement Coil using the supplied plastic stand offs and wire ties. Connect the top coil pigtail to the antenna feed clamp. Attached the ring terminal to the coax feed-point and now you are ready to tune your antenna.

This unit will work with most base vertical with a tune coil feed point.

The replacement coil kit comes with one Wolf River Vertical Base Replacement Coil, two plastic standoff brackets and wire ties.