updated 17-July-2007
Introduction
I have used a 2m HT mounted on the bike handlebars. I have also used a 2m HT mounted on my belt while riding a bike. Both produce fair performance for a 2m HT at 3 to 4 feet above ground. However, to maximize range for the Cornhusker State Games Cycling Tour (50 miles), I decided to try something a little different. I always wanted to mount a larger whip antenna on the bike, or at least a taller 2m antenna, in order to try to increase the performance. While a 2m colinear mounted on the bike would likely do the trick, I also wanted something that didn't tether me to the bike. At the Dayton Hamvention, you see all sorts of strange antennas - rubber ducks on yellow hard hats are fairly common. Actually, it sorta makes sense for better performance, although it does look really weird.
Below, you will see my first try at a bike-helmet mounted rubber duck antenna.
I cut out a piece of aluminum sheet, about 3" by 6". I drilled several 1/4" holes in this piece, including one for the SMA barrell connector at the end of the piece. The mounting holes were about 1/2" apart across the width and about 1 1/2" apart across the length. This gave me lots of options when securing it to the helmet, and also more air vent holes for my head ;-) The aluminum sheet was then mounted to the helmet with 2 each 8" plastic tie-wraps. A 3 foot RF cable with male SMA connectors was used to connect the SMA barrell to the Yaesu FT-60R radio.
This is how it looks when assembled. To make it look a little better, you can always give the mount a nice coat of paint to try to match the helmet colors. Black tie-wraps would also look better and be UV-resistant. When riding, I wore a belt in order to clip the HT somewhere. I clipped the FT-60R on my back and then ran the speaker-mic to my T-shirt collar around my right side. The RF cable went straight up my back to the helmet. Tighten all the SMA connectors down with a wrench, and lock the HT keyboard against accidental bumps while riding.
How did it work? Great! The 5 watts from the FT-60R plus the increased antenna height worked wonders on my test ride. The only thing I had problems with were low-hanging tree branches along the MoPac trail. On the open highways, this won't be a problem. A longer flexible antenna from Diamond or Comet would likely work a little better, but would also be more susceptable to overhead obstructions. (and it also look more strange to non-hams)
73 Roger
updated 17-July-2007