Bicycle Install. Please Help

[freecell]

when you make up your mind let me know. i have a base and mobile radio package currently available. you can pm me here in the forum or email me @:

http://www.firecommunications.com/site/contact.cgi

 

[Beetle]

the bicycle frame is the ground plane and because of the proximity and capacitive coupling to earth ground (just like passenger vehicles at 11 meters, or any other hf band for that matter)
is more than adequate at cb frequencies.

Compare the capacitance to ground of two skinny bicycle rims, plus the rest of the frame and its height above the ground with that of a four-wheeled vehicle with a substantial chassis, body and frame much closer to the ground.

Dream on.

 

[freecell]

two skinny bicycle rims that are much closer to the ground than the rims of standard vehicle tires. been there, done that and got the t shirt. nothing you can tell me about it.

 

[Cheech]

I have seen fire stiks have good SWRs on little to no ground plane. Try one of them with the tunable tip and see what you come up with. If it was me and I have thought about doing it I would go the CB route. VHF at high power is not something I want next to me. An HT would do the job for MURS but again little available for that band and comercial radios can be pricey.

 

[W5LZ]

Can it be done? Sure. Can there be problems in that 'doing'? Sure.
Okay, that part's out of the way. From there it can get a little complicated, depending on the bike, the antenna, and how the thing is ridden.
If you are looking for range, then a non-VHF frequency is probably your best choice. Unless you're talking about VHF/UHF and using repeaters, then I'd probably go with the repeater thingy, but that range isn't gonna be huge, sort of. If cost is a consideration, go with CB, it's cheaper, especially if this is a sort of "one time" thing.
You might also give a little thought to how you're gonna power this thing. Simple idea, but sometimes not the easiest to do, sort of. (Not sure of the kind of bike, so might be a difference or two there.)
Antennas.
Figure on using what you already have, or trying something 'new'. Making the radio like that antenna can get to be a problem since there usually isn't much 'metal' for that antenna to 'work against'. What's under that bike, dirt, concrete, whatever, will play a part in the antenna system just like it does on a car/truck/whatever. Gonna have enough of that "ground"? Beats me, try it and see. Don't 'fixate' on any one particular 'part'/aspect of that antenna system, look at all of it. Bunch of ways to 'finagle' a change to make it work. Maybe not real well, but it can work.
Any specific recommendations? Nope, can't, don't know what you have to work with.
Have fun...
- 'Doc

 

[pspdownloaddude]

We'll actually I don't have anything to work with. I'm going to need to buy everything new thus I'm asking for everyone's advice. So far, everyone is giving very good advice. I really appreciate it.

 

[pspdownloaddude]

I have seen fire stiks have good SWRs on little to no ground plane. Try one of them with the tunable tip and see what you come up with. If it was me and I have thought about doing it I would go the CB route. VHF at high power is not something I want next to me. An HT would do the job for MURS but again little available for that band and comercial radios can be pricey.

Which length of Firestick do you recommend? I'm also sort of confused. If I just buy the antenna, can I build my own mount kit. Is the threaded metal at the bottom a PL-259 connector? Or would I need to buy their mount kit. I'm new to this.

 

[Highlander_821]

You will need a mount. The Firestick is 3/8" threaded stud, IIRC. It sounds like Freecell can hook you up with everything you need. I would say that is a good way to go, give him a call or email. He certainly knows his stuff, and if you get the radios from him, you'll know they are tuned up and aligned correctly and will work right from the get-go!

I'll just say this about using CB---it will probably work alot of the time, under most circumstances, but CB is a funky band that changes wildly from day to day, month to month, and year to year. Right now, local communications can work quite well out to pretty decent distances, certainly 3-4 miles is not hard to do---but eventually, in a year or two, long distance skywave signals are going to start pouring in, and they can overpower local signals, especially when you are receiving thousands of them at once. So just bear that in mind.

If I may ask, are you doing this just for fun? Or is it something you are going to really need to rely on, like for a business or something? Just wondering.

 

[Cheech]

Which length of Firestick do you recommend? I'm also sort of confused. If I just buy the antenna, can I build my own mount kit. Is the threaded metal at the bottom a PL-259 connector? Or would I need to buy their mount kit. I'm new to this.

The 4 foot ones are the only ones I have ever used but longer is better so a 5 would be better.

 

[Beetle]

two skinny bicycle rims that are much closer to the ground than the rims of standard vehicle tires. been there, done that and got the t shirt. nothing you can tell me about it.

That's obvious.

 

[freecell]

have you actually ever measured the approximate ground coupling capacitance values of the following?

#1 a frame-on-body passenger vehicle
#2 a unibody passenger vehicle
#3 a mountain bike

 

[pspdownloaddude]

Thanks for everyone's input. I'll start getting this project together when I start my vacation in a few weeks. The CB would mostly be recreational. I wouldn't rely on a bike rig for a business.

 

[Moleculo]

Since he asked which was the "best" method, I still vote for the ham ticket. It costs nothing. There are just a lot more options available with regard to equipment, antennas, power levels, etc. with ham equipment. Heck, he wants to consistently get 2-3 miles only, which even 440mhz will do easily unless maybe he's in the middle of New York City or Chicago with all the big buildings surrounding him. On 2 meters, 220 mhz, or 440 mhz he could get some 1/2 wave mobile antennas and then not worry about all the ground plane issues on a bike. Hell a 440 antenna mounted on a bike rack would work great. And with all the used equipment on ebay or forums, he won't have to spend a bunch of cash. All it takes is the ability to pass a near free, 35 question test with all the questions and answers are given to you ahead of time.

Regarding the discussion on the groundplane of the bike: We haven't heard what the bike frame materials are made of yet. I saw some bikes at the shop that were all carbon fiber or similar materials, including wheels. Apparently they're very common now. Talk about a Ground Plane nightmare....

Anyway, my 2 cents is to just go the ham route...easier, better, and possibly cheaper in the long run.

 

[KI4MSJ]

I have my 817 mounted on my Mountain bike and it works great. Just remember that the radio mount is going to take a beating so, no jumping curbs.
Radio mounted to handlebars, then get a rack for the back with a bag and put a small Gel Cell battery in there. I use a 12v, 18Ah battery.

Next, to mount the antenna. You could use the rear rack for putting your antenna mount then run a ground strap from your radio to the antenna mount and then to the frame via the fender screw on the rear. There are a number of sites dedicated to this, including Yahoo Groups. Look up Pedestrian or bike mobile. There is even a club for it.

Check out the pics of my install here.........
http://s221.photobucket.com/albums/dd303/ki4msj/

 

[Mr Peregrine]

I have a Mobile/Skyway bike from 1984, I have a 102 whip bolted against the back wheel/frame with a Midland special too boot...