Base Loaded Vertical HF Antenna Coil

thingiverse

This is a form for making the coil for base or center loaded HF vertical antennas. It's intended for QRP work, although I suspect it would take a fair amount of power. Construction is straight foreward, just wind your chosen wire round the former which has a spiral grove to keep the turns separated. I've put in holes for terminals for radials and for banana posts for connecting the antenna wire. There are two end caps, one for taking the strain of the wire, the other with a hole for a BNC connector. You can mix and match as appropriate. I've now added a tapping ring (not in photo). You can put an M4 round head screw in this and use it a a sliding tap, which is easier than the probe clip.