Pedestrian Mobile Very Short Radial

Pedestrian Mobile Very Short Radial

This antenna is used by Hams riding a bicycle without the use of a trailing radial. Effectively, the bicycle from is the radial and is assumed to be trailing with a length of 1.0m.  Hence this model is only approximate but gives some insight into its operation.  For example, the model shows that the maximum radiation occurs in the oppoisite direction of the bicycle direction.  If the bicycle is travelling westerly the radiation occurs in a easterly direction. Dimensions are given in the 4nec2 file. Gain @ 30 degree take off angle = -11.1  dBi at 14 MHz.
Home TCA Index TCA Files Antennas Presentations Oarcproject  2013 Oarcproject 2015 Oarcproject 2017 Gallery Contact
3D antenna pattern, Horizontal Polarization. Antenna radiation is endfire with nearly vertical polarization. The maximum gain is only -11.1 dBi at an azimuth angle of 90 degrees.

Frequency Response: Optimized in 4nec2 for 14 MHz operation.

Impedance @ resonance =  153 Ohm due the very short radial Length of Radial = 1.0 m.  Vertical height only 2 m. Loading coil is large (19.7 uH)
Geometry of the Antenna. Short radial oriented along the x direction with the bicycle traveling along the -x direction. A loading coil is used to keep the antenna height small.
Polar pattern showing a maximum gain of -11.1 dBi at a 30 degree takeoff angle.