View Full Version : Bike mobile antenna/mount
KJ6EZQ
01-14-2011, 04:20 AM
I recently got a new bicycle and I want to put an antenna on it for ham radio. I have a MFJ-1729 mag mount antenna that I use occasionally on my car and I'd like to use that antenna if I can.
I'd like to use a clamp type mount for this antenna, but the MFJ-1729 uses a sort of unique connector at the antenna base (looks like a TV F connector). Are there any clamp mounts that would work with this?
I might upgrade to a new antenna trunk lip mount for the car which would allow me to get a compatible clamp mount for the bike. There is only one question in this case; should I go with NMO or pl259 type?
W8RNO
01-14-2011, 08:59 AM
sure you can clamp it to the bike, but what about a ground plane or counterpoise? (the other half of the antenna)
i would make a simple vertical dipole with wire and small pvc pipe and clamp it somewhere by the rear derailer. you can probably make one for less than $10.
W8RNO
01-14-2011, 09:04 AM
like this maybe? (this was my 5 min schematic in mspaint)
KE5MC
01-14-2011, 02:51 PM
I would go with the NMO mount. I believe the NMO is stronger than the UHF style at the point the antenna screws down on the mount. On a bike this will be important as the lack of suspension whips the bike as it goes over bumps.
...snip
There is only one question in this case; should I go with NMO or pl259 type?
KD8NPB
01-14-2011, 03:10 PM
sure you can clamp it to the bike, but what about a ground plane or counterpoise? (the other half of the antenna)
i would make a simple vertical dipole with wire and small pvc pipe and clamp it somewhere by the rear derailer. you can probably make one for less than $10.
Is it a metal bike?
That might be enough of a ground plane.
I'd put a Hustler CG-144 off the back of my bike if I had the choice. :D
2m simplex on the go!
KJ6EZQ
01-14-2011, 07:04 PM
Yes, it is a metal bike. That will be my groundplane probably. Thanks for the suggestions! :)
K1DNR
01-14-2011, 11:54 PM
nevermind...
M3KXZ
01-15-2011, 07:58 PM
Have a look at Dave Starkie's set up http://www.qrz.com/db/g4akc. He works bicycle mobile really well.
I've had a QSO on 20m with him in the past from my back garden. He was in Blackpool UK running 20W or so I believe, and I was in my back garden near Brighton UK. I know it's only about 250 miles in a straight line, but we were using SSB and I was running just 2.5W into a pair of homebrew 25ft speaker wire "no counterpoise" antennas (based on K9ESE design). Brilliant strong signals, and I was able to switch him in and out by changing the phasing of the antennas. These are the antennas that people say can't possibly work, but done proper then do well.
Definitely worth looking up Dave's info. Bicycle mobile QSO from UK to NZ! And that's with an onboard tuned ground.