GPS version






    Simple helicoidal

Picture of Vaisala's GPS version

When ON7EQ asked me if the QFH calculator on my site was reliable for higher frequencies, I just received a professionally designed GPS antenna from a Vaisala beacon. I determined the diam/height ratio to be 0.55 - probably quite directional vertically. Putting the data in the calculator gave exactly the dimensions of this antenna. (GPS - L1 - transmits on 1575 MHz).

So, at least up to 1600 MHz, things are very precise!

The antenna is just 55 mm long and 30 mm diameter.

Lower (grounded) side of the antenna...

Visible differences in size of the loops
... and a side view.

'Signal side' of the antenna. Detail how the PCB trace goes around the conductor.

'Ground side' again, all the centers soldered to ground.
Top of the QFH

Another complete view of the antenna

(c) John Coppens ON6JC/LW3HAZ mail