A successful morning today to convert my 40m vertical to an 80m vertical by adding a loading coil that I can switch out manually by just unplugging it. Nice and simple.
It’s not a great SWR curve due to the loading coil but I achieved 1.8:1 SWR at 3.79 Mhz, ideal for DX.
For the techies who want the dimensions: I wound 24 and a half turns on a fibreglass 2 and a quarter inch fibreglass former. The length of the coil itself is 3.5 inches.
Tip: If you are going to be QRO, use heavy gauge copper since this might generate some heat with the losses etc.
80m loading coil finished