Beware of ants! (Not a joke!)

[VK4WDM]

I will set the scene by describing my feedline system. The "tails" from my 70cm, 2m and 6m antennas are led into a heavy duty plastic box where they are connected via duplexer to a single feedline that leads back to the shack. the plastic box is sealed from the weather but has a couple of drainage holes in the bottom to allow any condensed water to escape.

Over the past few months the SWR on my 2m and 6m antennas has been a bit unstable at times but seemed to be fixed by replacing patch lines within the shack, but a week ago the 6m yagi went deaf and the SWR went extremely high. Nothing could be found at the shack end so I decided to drop the mast to examine the feedline-antenna connection.

While I was preparing to do this I noticed that the feedline had become an ant highway - they were going up one side and back down the other, and when I opened the plastic box I was confronted by an ant's nest full of bits of leaves, brown granules (presumably ant sh--), a wet gooy brown substance, and corroded connectors. (presumably from the formic acid that ants produce). The goo had even found it's way into the interior of the triplexer.

So one can add ants to the traditional cockatoos as a threat to antenna systems!

When I replace the box I will cover the holes with some fine stainless steel mesh.

73

Wayne VK4WDM

[VK3ALB]

Perhaps you could just leave the bottom of the box completely open? I think that would present a less inviting home for ants and other living things.