Radio Communications

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Radio Communications

Post by Mediocre »

Radio Communications
CB – Citizens Band radio. Used for communications over short distances. No license is required. Radios are limited to 4 watts of power. CB operates on the AM band like the AM music radio in your vehicle. When it gets to the edge of range the signal breaks up with static. Michiana Jeep Club uses channel 7 for most outings but is moving away from CB due to its limitations.

FRS/GMRS use the FM band like the music radio in your vehicle. It has a much clearer sound and transmits much farther with the same power (wattage). Sound quality is generally very good all the way to the edge of the range where it finally just stops. Michiana Jeep Club is using channel 18, 462.625, for communications on most club outings.

FRS and GMRS use the same 22 channels/frequencies and only the power/radio used differentiates which is which. They are UHF frequencies so they require line of site which limits their distance by the curvature of the Earth and obstacles.
FRS – Family Radio Service. Used for communications over short distances.
No license is required.
Radios have a non removable antenna
limited to 2 watts of power
Transmits hypothetically up to 2 miles. Trees, houses, etc. will greatly diminish distance.

GMRS – General Mobile Radio Service. Used for longer distances.
GMRS requires a license which is just paying a fee to the FCC for use. License is good for 10 years and anyone in your family can use the radio with the one license.
Limited to 5 watts of power in a handheld radio and 50 watts in a mobile radio (vehicle mounted).
Transmits hypothetically up to 35 miles. But since FM/UHF radio waves are line of site they are blocked by the curvature of the earth so 4-6 miles is realistic with no obstructions. Trees, houses, etc. will greatly diminish distance.

HAM – Amateur Radio
License with test required to transmit on HAM frequencies (HF/VHF/UHF). FRS/GMRS channels/frequencies are outside of the HAM radio defined frequencies.

GMRS Repeaters

A Repeater is equipment with an antenna usually mounted in a high place to receive your transmission and repeat it out on another channel. By being higher it has few obstructions and can be reached with lower power from farther away. Many have a 40 mile radius of coverage.

GMRS has an additional 7 channels that are used for repeaters to receive their signal on. Some repeaters are connected via the internet and will transmit your signal in their local area allowing coverage across the entire Midwest and farther.
Channel 15, 462.550, is a local Elkhart repeater channel that you can listen to hearing people from throughout Indiana, Ohio, Illinois, and other states. My first radio check from Mishawaka using this repeater was responded to from a person in Indianapolis.,, is a site where you can find GMRS repeaters in an area with their connection information. A special tone has to be setup on your radio for the repeater channel to receive your transmission. This is different for each repeater site and is available here. The site requires a GMRS license to register and view the information.

Requirements are listed above for the need for a license. We suggest using a package FRS/GMRS radio. Most of these, bubble pack, radios have a low power and high power button and can be used without a license using the low (under 2 watt) FRS setting.
A lot of members purchased the Baeofang UV-5R radios which is a Chinese HAM radio that is not FCC compliant because it transmits on the United States GMRS defined frequencies. Using this radio to transmit on GMRS channels is not within the licensing guidelines. A bubble pack radio set can be purchased for about the same price per radio than the UV5R so we do not recommend this radio. It has been since been superceded with a new model, GT-5R that does not transmit on the GMRS frequencies. For handheld radios the Motorola TalkAbout T600 or Midland GXT1000VP4 GMRS radios are a good choice. They can be set to low power mode (2 watts) so they do not require a GMRS license and have the ability to use more power (5 watts) and/or a repeater if/when you get a GMRS license.
Midland makes a good mobile GMRS (vehicle mounted) radio if you want additional power, larger external antenna and the convenience of a vehicle mounted radio. It is the Jeep Jamboree choice.
Midand radio site has a great writeup and the links to get your GMRS license. ... -i-get-it/ if you want to use more power, a mobile radio, or a repeater.
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