I'm trying a doublet antenna fed with ladder line. It is the DX Engineering WA-135 kit. I wanted to get the ladder line into the house to see if it is working OK. So I drilled an oval hole through the wall with a long concrete drill, and pulled the ladder line through the wall. The exterior wall is brick with mortar, and the inside wall is drywall, with a small air space between. I drilled through the mortar between 2 bricks.
I would like to seal around the ladder line to keep out insects. Are there any caulks or sealants that are safe to use around ladder line?