Oops! Photo of capacitance hat for bikemobiling was not where I said it
was. You can see it here:
http://www.geocities.com/CapeCanaveral/Lab/7378/990102a.jpg or
http://www.geocities.com/CapeCanaveral/Lab/7378/990102b.jpg
Essentially, because the bike doesn't present the same ground plane as
a full size car (and also because mobile antenna is optimized for ssb
portion of the band), you must find a way to achieve resonance. The
aluminum pole I use to put the antenna well behind the bike seat
(allowing comfortable mounting/dismounting) helps a bit, but for cw
operation on the lower bands, I require the added cap hat. It's just
made with a solid piece of copper wire and an alligator clip. You can
use an SWR analyzer to experiment with it. The thought of using a
"trailing wire" scares me! I have worked about 25 states, 4 provinces,
and 5 or so countries with 5W or less bike mobile cw. I rarely have a
problem getting at least one qso while riding, so mobile antennas and
low power can work from a bike.
By the way, one of the most useful features of a bike mobile rig is
"dial locking" capability. If your rig does not have a switch to lock
the dial, you may want to rig up a spring-loaded mechanical dial stop,
to prevent frequency shift when you hit a bump in the road. If you have
access to "QRP Quarterly", I had articles in Oct/98 and Jan/99 with many
more details.
Happy mobiling! 73, JC
| VE3JC John Cumming
Q | Delaware, ON CANADA
/\ | jbcumming@wwdc.com
@` /«----¬ hf qrp cw bicycle mobile
(¤) \(¤) http://www.geocities.com/CapeCanaveral/Lab/7378/
> Steve Ellington N4LQ wrote:
> For you unbelievers. Here is proof. Yes, a real /BM station! Trouble
> is: It doesn't work. The 40m Hustler seems to need more counterpoise.
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