This is a homemade eggbeater antenna for 435 MHz. The plans can be found on the Internet.

The antenna is right-hand circular polarized and are generally used for satellite transceivers.

The base was produced on a 3D printer and has 3 rare earth magnets to hold it to the roof of the car.

The car roof provides a good ground plane and helps to reduce the SWR of the antenna.

The phasing line is about 1.5 wavelengths instead of the .5 wavelength as called for in the plans.

The length of the elements is different from the plans because I used 1/4 inch copper tubing  instead of copper clad steel wire.