GMRS continues to grow with lots of new licenses being issued every month. There are a couple of things that you need to be aware of to avoid the disappointment that comes when you discover your expectations and the reality of this poplar radio service are misaligned.
In this video we’ll look at the top 10 things you need to know as you consider becoming a part of the GMRS community.
The local ham club in my home town is the Mile High Radio Club or MHRC. As a public service the MHRC recently committed to providing the entire local community with a GMRS repeater. This location is Idyllwild, California which is to say that we live relatively isolated in a very small mountain village high on Mt. San Jacinto in Southern California. Village elevation is 5200 ft. and is embedded in a forest of tall pine and cedar. Wildfires and earthquakes are a constant worry here because the infamous San Andreas fault is a few miles away. Also, Idyllwild has become a favorite tourist destination for hikers who use the countless wilderness trails and seem to create their own emergencies on a regular basis.
GMRS radio stands for General Mobile Radio Service. Prior to 1987 this service was known as Citizens Band Radio (CB).
GMRS is a licensed radio service in the U.S. that operates on frequencies in the UHF (Ultra High Frequency) band. These radios offer longer-range communication compared to Family Radio Service (FRS) radios, making them ideal for outdoor adventures and emergencies or simply a convenient mode of communication.
To use GMRS radios legally, you need to obtain a GMRS license from the Federal Communications Commission (FCC). Unlike Amateur Radio (Ham radio) a genuine FCC license requires no test but does include a $35 fee to be renewed in ten years. One GMRS license enables all family members to operate a GMRS radio. The FCC has operational rules to follow and they are simple and straightforward mostly along the lines of common sense and courtesy.
Typically, GMRS users have small two-way handheld radios that enable radio communication between any two points. If you already have an amateur 70cm handheld then you may have all you need to use GMRS; the two bands have very close frequency requirements. These little radios vary in price from as little as $17 (from Amazon or Radioddity) to hundreds of dollars. GMRS handheld radios power is rated in watts ranging from under 5 watts to 50 watts; their power pretty much determines its useful range. My own handheld amateur transceivers are inexpensive Baofeng UV-5R units which serve 2-meters, 220MHz, 70cm, and GMRS very well. However, the Baofeng doesn’t like the short simplex GMRS steps so my HTs are limited to repeater coverage.
The GMRS band uses two frequency ranges, simplex and repeater. The 22 available simplex frequencies begin with the transmit frequency 462.5500MHz and run in 25KHz steps to 467.7125MHz. Repeater frequencies also begin with 462.550 but have just 8 channels ending with 462.725MHz. Repeater power limit is 50 watts while simplex ch 9-15 is limited to 5 watts and 0.5 watts for ch 16-22. The receive frequency is always a 5MHz positive offset. This should look a bit familiar because the rules are almost the same for 70cm amateur band including the FM bandwidth and PL tone or CTCSS sub-audio tone. In fact, I recommend this antenna configuration for use on the 70cm amateur band except the element length should be bit longer at 6.5 inches.
As an old-fashioned ham operator, I begin any radio project with the antenna while the electronic equipment is secondary. This antenna is installed a few miles north of town where the elevation is 800 ft. higher so good coverage for the entire town is assured.
Repeater antenna required properties:
The inverted-Y antenna uses quarter-wave elements. This is a length of 15.4cm or 6.0 inches long. The angle between the two lower elements is 90o and adjusting this angle may be used to precisely impedance match the antenna to the coax.
My antenna was fabricated using small diameter brazing rod (any hardware
store) because it is very conductive plus stiff enough to withstand
fairly heavy wind loading. The antenna mast is a fiberglass tubing where
a 5-ft. long broom handle was used which is significantly cheaper, and
probably stronger, than online antenna fiberglass tubing sources. For a
precisely calculated element length use the following relationship:
This antenna is amazingly simple; the photo [in the original article] tells the whole story. I cut the elements a few inches too long and then trimmed each wire a fraction of an inch at a time while watching the network analyzer impedance chart. The antenna was tuned using a NanoVNA network analyzer. If you intend to build this antenna or experiment with any UHF antenna then there is very likely a NanoVNA in your future. They inexpensive, under $50, and I consider mine as an indispensable instrument in my shack. Using a repeater dramatically improves the performance of a handheld transceiver by receiving its transmitted signal and broadcasting that same signal as a substantially more powerful and wider coverage signal. The best way to extend the range of a GMRS handheld transceiver is to use a repeater if you have one in your community.
Antenna design analysis was performed on computer primarily using method of moments program 4NEC2 which is available free online while antenna measurement data was obtained using a NanoVNA vector network analyzer. The NanoVNA is available online from Amazon or AliExpress and its computer software is available online for free.
Morgan County’s independent backup emergency communications network has been busy making the most of their radio experience and the gift of two radio towers from the county to build out a secondary layer of connectivity in case of major disaster locally.
The incorporated group—Morgan County Emergency Communications Network, Inc.—will host a Morgan County Preparation Day this Sunday, November 3 to talk about their efforts and what local households can do to be prepared for unforeseen challenges.
Their first event, to be held at the South Morgan Volunteer Fire Department meeting hall starting at 1 p.m., is an informative training that’s open to the public.
Run by the Morgan County Emergency Communications Network, the event promises a free emergency “Go Bag” to registered attendees. That will include a two-way emergency radio which could be used if other forms of normal communication with emergency authorities don’t work.
Network organizer John Petersen said one radio will be given to each of 200 families.
The Morgan County Commission contributed county funds to help pay for the radios.
In addition to these giveaways, the Preparation Day lineup includes talks by Petersen, Morgan County’s Office of Emergency Services Director Jason Hoover, Morgan County Sheriff’s Chief Deputy Johnnie Walter, Morgan County EMS head Kevin Duckwall, Morgan County 911 Director Marshall Younker and a fire service presenter. Each will talk about likely emergency scenarios in this area, how those would affect families and what infrastructure is in place and is important for community operations and recovery.
Network presenters will include Lori Marino of American Contingency. She will talk about resources in place for disaster situations and what households should have on hand to meet the disruptions of an extended disaster event. John Walton, Vice President of Morgan County Emergency Communications Network, Inc., is set to train attendees on the use of two-way radios and talk about communications in an emergency situation.
Petersen said his group, which holds a Memorandum of Understanding with the Morgan County Commission, is an “integral part of the county’s emergency response plan.”
Made up largely of skilled amateur radio operators, the Morgan County Emergency Communications Network is “actively building out a county-wide infrastructure” to add additional communication options for county residents, responders and those outside the area.
In March of 2021, the county gave the group an unused tower at The Pines and in June of 2022, the county gave the group an abandoned tower and building on Cacapon Mountain to use as part of a backup radio network. County officials also agreed to share space in a planned backup Office of Emergency Services building with the Morgan County Emergency Communications Network. Construction of that building has been delayed by the high cost of bids.
“MCECN exists for those unfortunate times when nothing else works,” Petersen said.
He pointed to the events in Tennessee and North Carolina following Hurricane Helene, which created unprecedented and catastrophic flooding that isolated many.
“[It] should serve as a warning that we must come together as a community to help each other make emergency response plans—before a disaster strikes. If we wait until one is upon us, it will simply be too late,” Petersen said.
Morgan County Emergency Communications Network, Inc. is installing radio repeaters on local towers to enhance radio connections. Petersen said his network of members can monitor that two-way radio traffic and “act as an intermediary” between the people and law enforcement or 911 if needed.
The Preparation Day is meant to get households thinking about their level of preparedness, said Petersen.
“You need to be aware of the possibilities in order to be prepared,” he said. “You can’t reasonably respond unless you’re informed.”
“When these things happen, if you haven’t thought about it, you’re already out of time and money and options,” Petersen said.
