Q: What types of two-way radios are available?
A: You can choose from 2 configurations:
1. FRS (Family Radio Service) models—lower-power units that operate with a half-watt of power. They can transmit on 7 FRS channels and 7 shared FRS/GMRS channels (channels 1-7)—a total of 14 channels.
2. GMRS (General Mobile Radio Service)—higher-power radios that, for models used in outdoor recreation, typically offer 1 or 2 watts of power. GMRS signals can travel on any GMRS or FRS bands—a total of 22 channels.
Most radios now have all 22 FRS and GMRS channels available. The Federal Communications Commission (FCC) requires a five-year license to use GMRS bands. More details about these 2 types of radios can be found later in this article in the "Channels and Privacy Codes" section.
Q: Range claims ("Up to 25 miles") are often prominently displayed on packaging. How realistic are such claims?
A: Range claims are based on transmissions in optimal conditions. This means having an unobstructed line of sight between you and another radio operator, preferably from a high vantage point in good weather.
Real-world conditions, though, are usually not optimal, and the range of a two-way radio is commonly much less than the maximum possible.
So what is realistic? Regardless of a unit's published optimal range, in roughly 90% of situations, a radio's actual range will be about 2 miles or less.
Why? Several factors can inhibit two-way radio performance:
The human body (which is dense and watery) can also block radio waves. You may boost reception of incoming signals if you attach a radio to a section of your pack that remains away from your body instead of clipping it to your belt.
Potential causes of radio interference are as random as nature itself. So yes, your two-way radio results may vary.
While dense forests or multiple ridgelines can be major impediments to radio signals, scattered trees and bushes are mostly transparent or "translucent" to these signals. So even in forested or hilly territory, two-way radios generally do a fair to good job of transmitting short-range signals.
A chief benefit of higher-powered radios (1- or 2-watt models) is their ability to fill in coverage dropouts (behind hills or buildings, for example) that often occur within the line of sight of a radio user. The higher power tends to improve the overall quality of the signal.
Even so, for people who typically use their radios in fairly compact areas—a ski resort is a good example—a lower-power unit could serve your needs quite adequately.
Q: In what conditions can a two-way radio deliver its maximum range rating?
A: From a high vantage point looking down into a flat valley or lowland area with minimal tree cover. Flat, obstruction-free settings are also good for transmitting radio signals, but the addition of height greatly boosts your range potential.
One example: a large lake with nearby hills—a setting where two-way radios are often tested. During such tests, three or more radio users may be deployed around a lake:
Depending on what type of radio is being used, the boat and lakeshore users can typically communicate at distances of 4 to 6 miles. The hilltop user and the boat use can potentially hit the top of a radio's range (if the lake is large enough and distant topography does not interfere).
From high vantage points—say, a 1000' hill in the vicinity of a population center located below in an open valley—you may find a radio has too much range. It's possible you'll hear people talking on every channel. In such an ideal situation, even a half-watt radio could send its signal 25 miles or more.
Ultimately, a key rule for optimizing coverage is achieving good line of sight. You will increase your ability to increase your range as you increase the elevation of your position. Attaining a high point above an otherwise flat area can be a huge benefit toward optimizing your radio's maximum range.
Q: What about range over open water?
A: Someone 6' tall, for example, standing on flat beach looking out over the ocean can see roughly 3.5 miles to the horizon, when the earth begins to curve away. Another 6' person standing on a raft in calm water could communicate with the other 6' person from an approximate distance of 7 miles—since nothing would be interfering with their line of sight.
Enable both individuals to climb 10 feet in the air and the distance expands to 10.7 miles. At 50 feet high, the radios could communicate at 20.1 miles. The potential range escalates as the height of the radios increases.
Q: Beyond range claims, what other clues can I use to spot a high-performing two-way radio?
A: Roy Reese is chief product engineer of Giant International, a Georgia-based manufacturer of two-way radios that licenses products to a major electronics firm. For this topic, REI sought out Reese for his technical expertise.
"There are a lot of different ways to express power," says Reese, "and some numbers are put on packages that have nothing to do with the reality of a radio's capabilities.
"What really matters is an antenna's 'effective radiated power' — a measure of what's flying off the antenna. It doesn't matter how big the amplifier is. What's important is how effectively an antenna is radiating its power level."
Two-way radios, Reese explains, capture waves that are about 12.5" in length. "The effectiveness of the antenna is crucial in coupling with that power of the transmission, and generally a bigger antenna is better," he says. "But you have to consider how well a big antenna is going to fit in your backpack. Naturally, the people in industrial design want something small and sexy with a long range. You can't have both."
For two-way users hungry for peak power in a small unit, Reese suggests looking for radios with antenna and radio bodies of equal or near-equal lengths. "Think balanced," Reese says.
Q: How many channels are available for a two-way radio user?
A: Most radios offer 22 channels and up to 121 privacy (or interference-elimination) codes for each main channel.
FRS: Free Service for Short-Range Use
The Family Radio Service (FRS) band sparked the two-way radio popularity explosion. It was created by the FCC in 1996, with 7 channels provided specifically for two-way radio users. It's intentionally limited to a power output of half a watt, which provides a maximum range of up to 6 miles under ideal conditions. FRS users can also use the 7 shared channels with GMRS for a total of 14 channels, provided you broadcast using the maximum half-watt of power.
GMRS: Licensed Service Adds Channels and Range
Inevitably, consumers wanted more power, greater range and more channels. Manufacturers responded by introducing recreational radios that also used the General Mobile Radio Service (GMRS) band. Originally allocated for commercial use, GMRS offers 8 additional channels plus the 7 shared GMRS/FRS channels for a total of 22 channels.
Though GMRS technically allows a maximum power output of 50 watts (used for base stations), most recreational hand-helds offer 1 or 2 watts to keep size and weight low. To operate a radio that uses GMRS channels, a 5-year family license is available from the FCC for $85 (as of October 2007). Note: You do not need a license before purchasing a GMRS-capable two-way radio, and REI does not report buyers of a GMRS radio to the FCC. Go to www.fcc.gov for more information on licensing (Form 605).
Tips for Locating a Clear Channel
In busy areas, such as a ski resort, 22 channels can quickly get occupied. As a result, many radios provide a CTCSS (or CDCSS—Continuous Digital Coded Squelch System) that allows you to subdivide main channels with the use of privacy codes. Rather than trying to communicate with a friend simply by using Channel 5, privacy codes let you connect with a combination of channel and code—for example, Channel 5 and Code 3.
When you have searched all the main channels and can find no absolutely clear channel, this is your next-best option. The use of CTCSS or CDCSS "codes" can minimize (but not eliminate) the amount of unwanted chatter on the main channel the user would otherwise hear.
If you and your friend agree to speak on Channel 5/Code 3, your radios will send out tones (a low buzz or a subaudible data stream, Reese says) that a radio receiver detects. This activates the speaker of the recipient so the message can be heard.
Switch to Channel 5 and code 0 (no interference code) and you can hear all the chatter taking place on that channel — usually a cacophony of many voices speaking over one another. The use of an interference code, which essentially encodes your voice with an additional identifier, allows you to control what you hear.
Note: In cases where two parties on the same main channel are transmitting simultaneously, the usual result is no one can hear anything (unless one pair of the radios is much closer in proximity than the others). This occurs regardless of the CTCSS setting.
Important: A "privacy code" does not make your communication private. Any radio user, including people unknown to you, can randomly dial up your chosen channel/code combo and listen to your conversation. This is why some manufacturers alternately call this feature an "interference-elimination" code. But by any name, it's a highly desirable feature—it boosts your odds of locating a relatively clear communication path in places where many parties are using two-way radios.
All two-way radios have a "monitor" function. When it is activated, it will override the code settings entirely and open the receiver response unconditionally. What would be heard on a clear channel is just hiss, while a busy channel would have voices. Naturally, you will select the main channel and privacy code where you can create a chatter-free frequency.
Analog tones (CTCSS) are numbered 1 through 38, and are generally implemented across brands in a compatible fashion. Digital codes (CDCSS) are numbered 39 and above (up to 99, 121 or even higher,) and may not map exactly from brand to brand.
Q: What other factors should be considered?
A:High power and added features have their advantages, but if you're main goal is to simply keep track of your family while on a ski mountain, a basic model may be sufficient for your needs.
Below are some topics you may wish to ponder.
Most two-way radios use all 22 channels available. They do this by taking advantage of the fact that GMRS channels allow for higher power output (between 1-5 watts) than do FRS channels. Note that any radio—even if it has 2 watts of power—automatically switches down to a half-watt when operating on the 7 FRS-specific channels.
FRS-only models that put out the FRS maximum of a half watt can operate on all 22 channels, too, but will give you the same maximum range—5-6 miles—even if it's on a GMRS channel. These less-expensive models are ideal for users who know they'll be using their radios at relatively short distances.
Keep in mind that both FRS and GMRS radio signals travel by line of sight. This means that terrain, weather and other factors will often reduce any radio's maximum range in the field. Expect a maximum range of 5-6 miles under ideal conditions for a radio that has a half watt of power and a maximum range between 8-25 miles for radios utilizing 1-2 watts.
Size and Weight: Shop units by size, shape and weight, especially if your intended use is backpacking. You'll want a lightweight radio that isn't bulky. If you're a skier or mountaineer, look for an ergonomic shape so you can easily use it with gloves. As noted earlier, consider a model where the antenna length is similar to the length of the unit's body.
Calling and Paging Features: Pre-set "calling" tones can let you grab the attention of other members of your party before you start talking. You can also set some models to vibrate instead of making an audible tone.
Scanning: This allows you to cruise through channels in order to find the one that your group is using. You can also use this feature to quickly locate an "empty" channel for your group to use.
Keypad Lock: This allows you to lock your settings in order to prevent them from accidentally getting changed as you go about your outdoor activities.
VOX: The voice-activated (or "VOX") feature begins broadcasting automatically when you speak in the direction of the radio, thus letting you operate it hands-free. Mountain bikers and skiers find this to be a useful function.
Noise Filter: This allows clearer signals and enhanced range.
Weather Radio: Tap into the NOAA weather band stations for local forecast and conditions. This is a very handy feature for anyone, but can be essential for backcountry adventurers.
Headset Jacks: Jacks for microphones, headphones and microphone/headphone combos allow for hands-free operation. This is ideal for active sports—skiing, kayaking, cycling—where you might not be able to stop and answer the call.
Radio/GPS Combo Units: Though more pricey, Garmin RINO (Radios Integrated with Navigation for the Outdoors) units offer all-in-one nav/comm capability. A key advantage is peer-to-peer positioning, which allows you to broadcast your location coordinates so they appear on your fellow RINO users' screens.
Most two-way radios run on standard AA or AAA batteries. Others come with their own rechargeable NiMH (nickel-metal hydride) or NiCad (nickel-cadmium) battery packs. A few can accommodate either.
In general, the higher a radio's power output, the faster it will drain your batteries. Look for models that send the unit into a low-power, battery-saver mode after a certain amount of time has elapsed between broadcasts. Or consider a solar charger for in-the-field replenishment of NiMH and NiCad batteries.
Any two-way radios broadcasting on the same frequency (FRS or GMRS) and supporting the same channels will work together. Keep in mind, though, that to get full use of your radio's other features, you'll need another radio with the same features. Thus, it makes sense to buy in pairs.
When people buy new radios, they are sometimes frustrated by their inability to connect with older radios. Since older radios cannot send out the number of tones that newer radios can, this can usually be solved by setting the new radio to channel 1, code 0. The default setting for new radios is channel 1, code 1.
This is explained in most user manuals. And here's something you should know about manuals: While it is natural to break out newly purchased two-way radios, insert batteries and begin experimenting with them, it's a smart move to sit down and devote some time to reading the user manual thoroughly. You'll usually learn a pointer or two that will make operating your radios a simpler task.
Two-way radios made for use in the USA are generally not legal to use outside North America. In 2005, the frequencies used for two-way radios in the United States and Canada were aligned, both meeting the same requirements. Mexico formally allocates only FRS channels. Other countries may use these frequencies for police, military or other applications.
Two-way radios are practical devices for staying connected with your group.
Bottom line: For short-range use in uncrowded areas, FRS channels may be all you need. For longer-range use and more channel options, you'll want GMRS channels. For ultimate convenience and versatility, choose one of the new radio/GPS units.
Contributor: David Tynes, REI product information specialist.
By T.D. Wood
Read Author Bio
Last updated: 02/18/2014
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