This is a capacitive coupler for tuning Short Loop Antennas (STL).
It is an evolution from the ‘Patterson Match’ aka military loop from 1967, this is my fifth generation of: Simplified Patterson Coupler
More build description and use here: Hexagon Coupler v1 from the blog Electromagnetic Adventures.
(please contact me if instruction is unclear so I can improve)
Add copper tape to inner, outer and middle hexagon. Thread inner and outer hexagon.
Secure each shaft with disk and 2 self-threading screws.
Solder wires, add some foil to solder wire away from hexagons, Be careful and work fast to not melt 3D model:
Tested only with 10W but it should be able to handle more, ensure that distance between foils are > 1mm and cut away excess to avoid short circuit
Warning❗
Keep away when in operation, use the protective cover, because when in resonance the voltage can be several 1000 volts and burn your fingers.
The author marked this model as their own original creation.