HF Helical Antennas: Theory and Practice 

HF Helical Antennas: Theory and Practice

By: Igor Grigorov VA3ZNW

Shortened HF Helical antennas have been used by radio amateurs in activity on the Air during a long time. For example, shortened vertical helical antennas have been used in hand held CB radio stations (it is 11- meter HF band) from the 50- years of the 20- century. Some manufacturers produce shortened helical antennas for military and amateurs for lower HF bands- from 3 to 20- MHz. As well shortened helical antennas are widely used in VHF/UHF radio, as amateurs, as commercial.

Picture 1 Hand-Held CB Radio Cobra with a Shortened Helical Antenna

Picture 2 Hand-Held VHF Radio United with a Shortened Helical Antenna

www.antentop.org

Page- 05