This is remix from http://www.thingiverse.com/thing:1725339
The idea is make 3 or 4 band lightweight portable vertical antenna.
The dimensions and simulations and measurements coming soon.
Work is in progress.
The holder is designed in Openscad and use cable ties.
- Added simulation of 40,20,30m version with base loading coil.
- Added radial end insulator in STL and OpenSCAD
- Added reduction for BNC connector and cover when connector is not used
- Coil inductance measurement
- Improved coil holder for better fit of cable ties
- Bottom fixing for fibre glass pole - 6m Decathon travel pole or cheap 6m pole Agepoch from Aliexpress.
- pole guying part for top of pole - 5mm and 10mm diameter
- Field test of 40/30/20m version with VNA, 4.1 m lenght of vertical element, 5.25m radials
Antenna is really narrow on 40m as expected.
- Plots from VNA.
Only coil and holder need support, other parts without support..