Marine Mobile With a Saltwater Antenna

The idea of saltwater as an efficient groundplane has been known for decades. But what if you filled a tube with saltwater for an antenna and used a freshwater lake as your ground? Here is a photo taken November 29, 2002 of the first successful test of an Ionic liquid Antenna from a boat.


This was the scene just before heading out. I used a fiberglass pole to support the 10' white PVC tube containing a heavy concentration of saltwater. The temperature started out in the upper 50's but dropped to just 31 deg. by the end of the trip.

The antenna tuned nicely on 10, 17 and 20 Meters. I ran 10 Watts most of the time, occasionally powering up to 20 Watts. I made contacts from Seattle to Georgia and Alberta to Mazatlan (XE2/W6DXO) between the three bands using an IC-706 MKIIG and MFJ 941-E tuner. You can just see the 10 foot long, 3/4 inch diameter white antenna strapped to a black fiberglass fishing pole. More details on the ILAs are in my antenna section.

The small sticks at the stern are for hanging a pair of solar powered garden lanterns "borrowed" from my wife's garden. For a ground I used 18 feet of coax braid taped to the hull. 

Credit for the creation of the saltwater antenna (ILA or Ionic Liquid Antenna) goes to David Hatch, N9ZRT in Green Bay Wisconsin.