Researching best solution for Car to Car communication over 1-5 miles

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EvilG

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As a member of a small car club, i have been tasked with re-thinking our communications while driving. We currently use Baofeng FRS radios which are pretty lousy.. We take group drives of 25-50 cars around NY State. Some areas with mountains, etc and i'm not looking for miracles.. but 1-3 miles line of site should certainly be possible... the basic communication structure is few to many.. 3-5 broadcasters with up to 30-40 receivers.

i see my options as follows
1. license the broadcasters with GMRS equipment broadcasting at 5W on the FRS channels, the receivers will have FRS radios.. this way they should be able to listen in on the organizers broadcasting instructions, traffic, diversions, etc
2. use MURS radios (which of course don't require licenses)
3. set up some sort of moving repeater at the middle of the group (if this is even possible)
4. something i haven't thought of??
 

Hans13

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1. license the broadcasters with GMRS equipment broadcasting at 5W on the FRS channels, the receivers will have FRS radios.. this way they should be able to listen in on the organizers broadcasting instructions, traffic, diversions, etc
2. use MURS radios (which of course don't require licenses)
3. set up some sort of moving repeater at the middle of the group (if this is even possible)
4. something i haven't thought of??
1. Get GMRS licenses and use up to 50 watts mobile on the GMRS only channels. Check out the new 45 watt Midland mobile coming out. Unlicensed can still listen as most, if not all, bubble packs include GMRS. No license is needed to listen to any of the public (nonencrypted) radio services.

2. MURS with mobile antennas on the vehicles at 2 watts. Meh.

3. That is possible. Licensed GMRS is a good candidate (not sure).

4(a). CB radio.

4(b). Amateur radio licenses and local repeaters.

4(c). If there is cell data service; Zello.

4(d). There are probably more.
 

Hans13

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Also, make sure that you are using eternal antennas. Antennas inside the metal cage will perform very poorly.

BTW, there are no FRS certified Baofengs, as far as I know. There is one GMRS certified; the GMRS-V1 based on the UV-82.
 

RFI-EMI-GUY

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GMRS works better with full +/- 5KHz deviation. The Midland mobile, the bubble packs , most cheap radios run 1/2 full deviation.
 

popnokick

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+1 on getting the antenna OUTSIDE of the vehicle. Handheld radios used with their stock antennas inside a vehicle will be severely limited in range. You'll get an immediate range boost simply by using an external antenna.... even a magnetic base antenna connected to the antenna port on the handheld radio. This is assuming very few of your members will not want to permanently mount antennas on their vehicles, but only put them on temporarily during club rallys. But GMRS is your best bet... you'll be able to run more power and use detachable antennas. When in the car with the HT, connect the external mobile antenna. When you step out of the car, put the rubber attenuator... err, antenna.... back on the HT. BETTER solution for distance: a full-power GMRS mobile radio such as the new ones from Midland mentioned earlier in this thread. Do not use the mobile 45W radios without an antenna OUTSIDE the vehicle.
 

jonwienke

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GMRS works better with full +/- 5KHz deviation. The Midland mobile, the bubble packs , most cheap radios run 1/2 full deviation.
Which means that if the transmitter is set for wideband, the receiver audio will be clipped or overmodulated. The correct answer is to set the transmitting radio to match the receiving radios. Going narrowband reduces range slightly, but ensuring all radios are set narrowband will prevent excessively quiet or overmodulated audio and reduce adjacent-channel interference.

+1 on getting the antennas out of the vehicle, regardless of what radio service you choose. CB radio is better for rough terrain; 27MHz will refract over hilltops and penetrate woods and foliage far better than GMRS UHF. The disadvantage is that it requires much a larger antenna than UHF, and it must be installed outside the vehicle. UHF is line of sight, so you'll have dropouts in coverage in hilly terrain. But if the receiver has a FRS walkie-talkie, they will get some reception if they keep it in a window or on the dash--UHF can get through car windows into the vehicle interior, where CB won't.

Your mention of a car club leads me to suspect that the members will probably be reluctant to drill holes to permanently mount external antennas, so I would lean toward having your "talkers" use 50W GMRS radios (with permanent external antennas), and the "listeners" use Baofengs (with external mag mount antennas if possible) or FRS walkie-talkies (with a reminder that they need to be kept on the dash so the antenna can "see" out the window). 50W will go a mile or two even in suboptimal conditions, and you can have multiple "talkers" spread throughout the convoy so that even if the "talker" at the beginning can't be heard at the end, the message can be relayed from front to back (or vice versa) so that everyone gets the message.
 

bharvey2

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Is your car club just a club or does it engage in any business or philanthropic activities? Maybe it could qualify for a Part 90 / itinerate license. Last time we (the company I work for) renewed I think it was $300 for 10 years. It'd probably be cheaper that trying to get GMRS licenses for all of your members. I'm just not sure of your eligibility. Maybe some of the guys who interact with the FCC on a regular basis can weigh in.
 

SteveC0625

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As a member of a small car club, i have been tasked with re-thinking our communications while driving. We currently use Baofeng FRS radios which are pretty lousy.. We take group drives of 25-50 cars around NY State. Some areas with mountains, etc and i'm not looking for miracles.. but 1-3 miles line of site should certainly be possible... the basic communication structure is few to many.. 3-5 broadcasters with up to 30-40 receivers.
Your statement about "line of site" (actually sight meaning vision) is the most telling. Without external antennas you're not going to get the upper two miles from handhelds. Even then if they're not 5 watt units, even a mile is stretching it. FRS radios are 1/2 watt max. They'll receive a 5 watt signal over a greater distance, but won't be able to reply.

My wife and I use GMRS when we convoy through the Adirondacks and else where. I have a 25 watt mobile in the truck with a 1/4 wave antenna on the roof with good ground plane. She's using a 5 watt handheld with a speaker mic, and no matter how I explain it to her, she just leaves the radio in cup holder. If I take the mic off, she complains that it's too big for her to hold. (There are compromises to married life that are essential. This is one of them.) Our best distance is about a mile because the handheld is below the level of the windows of her Jeep. I bought a mag mount for her radio and will try that out this summer. It should improve performance drastically, but I'm still leery of a full three miles or more.

VHF travels better than UHF for this purpose, but you're stuck with 2 watt MURS if you want to stay totally legal without licensing. And that's an investment most of your members would be unhappy with because of limited range.

As mentioned above, it's possible to get a Part 90 license on one or more of the itinerant VHF frequencies. If your club is incorporated, it should not be a problem to do this. This opens up lots of possibilities. 5 watt handhelds and 25 to 50 watt mobiles are readily available both new and used. Installed antennas are preferable, but a mag mount may well be enough for some of your member's needs.

And, since you're inquiring for a car club, there's a simple fix for those that might be concerned about a mag mount damaging the finish on the vehicle. Get a piece of clear "helicopter tape", cut it to a circle a bit larger than the mag mount base, and place it on the roof or trunk lid of the car. This stuff is darned near impregnable, and surprisingly easy to find. Most bicycle shops stock it to protect the finish on bike frames. Avoid crimping or otherwise damaging the coax when you route it into the car.
 

ladn

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+1 on getting a Part 90 license and sharing the licensing cost among the members. It's probably more cost effective than each member/family getting a GMRS license. Since the club is very mobile, I'd look into getting licensed on an "itinerant" frequency for a very wide geographic area.

And definitely use an outside antenna!
 
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