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Tech Tip 71 - FRS Radios for Geeks
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Sometimes, you need to stay in touch with your family or a bunch of friends instantly, but don’t have your computer screen in front of you to IM. Cell phones are fine to talk to one person, but how do you hail a group of people right now? You might have overlooked FRS, or just don’t know really what it’s about. Let’s take a look. |
With Instant Messaging (IM), Voice over IP (VoIP), Short Message Service (SMS), and dozens of other computer-based communications acronyms stuffed in your Geek memory, how about this one – FRS? I’ll give you a hint - it doesn’t run on your computer, but it’s a way to stay hooked up with your buddies that you shouldn’t pass up.1. CB It’s Not!
Truckers use radios that are technically Class D Citizens Band. They operate at 27 Megahertz (MHz), which is down in the shortwave radio band that is full of skip. You might occasionally be able to talk to someone hundreds or even thousands of miles away, but mostly you have just too many people trying to talk to each other. Class D CB uses Amplitude Modulation (AM) which was popular and cheap fifty years ago when Class D was designed. Unfortunately, AM is very susceptible to interference with all sorts of squeals and howls. |
Your idea of two-way radios might be CB, or Citizens Band, right out of Smokey and the Bandit. Sure, the guys driving 18-wheelers still use CB radios, but we are geeks and we’re not interested in the latest location of radar speed traps on the Interstate.2. FRS Has Roots in Class A
Actually, there was another form of Citizens Band radio that predates the “10-4, good buddy” type. It operated in the UHF (Ultra High Frequency) band near where commercial two-way radios for police cars and delivery trucks are now. This was Class A Citizens Band, but almost no one had heard of it because the equipment was too expensive, the rules too restrictive, and it required a complicated license from the Federal Communications Commission, or FCC. In the eighties, this part of the radio spectrum was converted to the General Mobile Radio Service, or GMRS. The FCC license was easier to obtain, the rules relaxed, and the equipment less expensive and easier to operate. The GMRS radios used Frequency Modulation (FM) that rejects interference better than AM CB radios. Even if another station is on the same channel, but with a weak signal, you can usually talk right over them to your close-by buddies and the other party probably won’t even know it. |
3. FRS Brought to You by Tandy
GMRS was mildly successful, which we’ll get back into later, but electronics retailers wanted to sell more radios. The biggest retailer of all pushed a new concept called Family Radio Service, or FRS. That retailer is Tandy Corp., but we all know those folks as Radio Shack. In the mid-nineties, Tandy went to the FCC and convinced them that this new FRS could share the radio channels with GMRS. Instead of the 5 Watt mobile radios common in GMRS, the FRS radios were usually handheld units limited to 500 milliWatts, which sounds better than “half a Watt.” |
4. Putting FRS to Work
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What can you do with an FRS radio? Suppose your gaggle of friends descend on the local swap meet looking for an 8-inch floppy drive to finish off that early microcomputer for your computer museum. You split up to cover all the aisles as quickly as possible. How are you going to rally the troops when you spot the object of your desire? If everyone has an FRS radio plugged into an earphone, the moment you press the “Talk” button, they will all hear you. No dialing numbers or setting up chat groups. Just press and talk.5. Privacy Codes
 I mentioned the interference and lots of people talking on CB radio. It’s something you certainly don’t want to listen to for very long. Even on FRS, there are others sharing the channels you are using. Many FRS radios now have privacy codes available. When you set a privacy code on each radio in your group, all other transmissions are ignored. Only when a signal with your privacy code is present will you hear the call.
Privacy codes are not new to two-way radio. Most privacy codes are implemented with CTCSS, or Continuous Tone Coded Sub-audible Squelch. That’s a mouthful, but the idea is pretty simple: by adding a low frequency tone to the signal on the transmitter side, your signal is now unique. The receiver will filter out all other signals and keep the speaker quiet. When the receiver hears your tone, the speaker is activated and the recipient hears only your call. |
6. Look Ma – No Hands!
FRS has some real practical uses too. Suppose you have your head in the wiring closet trying to troubleshoot a network problem and you need to talk to your helper who is running tests on the equipment in the other room. You can try yelling down the hall, but that bothers the other workers and it’s hard to yell when you have a punch-down tool in your mouth because your hands are full of wires. Some FRS radios come with VOX, or Voice Operated Switch. When the radio microphone picks up your voice, it automatically switches on the transmitter. Thus, you and your helper can talk back and forth almost like you are in the same room. VOX is real handy this way, but it isn’t perfect. There is a tiny delay when the VOX circuit picks up, so it will cut off the first part of your first word. If you get in the habit of says something like, “Ah, George did that fix it?” you will not have trouble with a first syllable “clipping” problem.
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I know my FRS radios are indispensable while adjusting the UHF antennas up in the attic for the best reception of 7. Economical, Too
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FRS radios are small, portable and can be really inexpensive, too. They’re cheap enough to keep a pair in the toolbox or in the glovebox of the SUV. Take a look at the 8. Ranging Out
The specification most FRS manufacturers quote is a 2 mile range. FRS radios use UHF radio frequencies that depend on line-of-sight for maximum range. The signals will penetrate buildings and trees when you are close by, but especially after a rainstorm when everything is still wet, you are talking a few hundred yards. If you want range, sit on a hilltop and your distance will pick up significantly. If both parties get up on hills or even mountains, you are going to “range out” to dozens of miles. That’s the nature of UHF radio. FRS is intended for close-in communications, so being within a block or two will usually work pretty well. |
9. GMRS if You Get Serious
I mentioned that to use the GMRS channels, you need an FCC license. The license is expensive, at about eighty bucks for five years (a little over a buck a month), but one license is good for all of your immediate family members. The GMRS channels are generally less busy than the FR-only channels, so you will get less interference and better range.
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For more details on a GMRS license, you can go right to the 10. Repeaters for Really Getting Out
I explained that if you get up to a high spot, your range would extend considerably. If you upgrade to GMRS, you can avail yourself of a feature called a repeater. Years ago, radio amateurs started putting radios on tall towers and mountain peaks and set them up so they could listen to one channel and repeat the signal to another channel. GMRS copied this scheme. That’s why GMRS channels come in pairs split between 462 and 467 Megahertz. With your simple low-powered radio, you can send signals that are repeated from the mountaintop to a huge coverage area.
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There are commercial GMRS services that will sell you repeater service, but you don’t have to go that way. There are public service organizations that maintain repeaters that you can use for minimal club dues. One such group is
Final Words
Pick up a pair of FRS/GMRS radios while the price is right. They might just be a handy gadget to save some steps while shopping, visiting a theme park, or fixing something around the house or the workplace. Or, they might lead you to a whole new hobby with involvement in local emergency organizations. I hope understanding the features and uses of FRS and GMRS services will help you choose what is best for you without getting confused by the legal gibberish of the FCC or the claims of the equipment manufacturers. It really is a lot of fun for the whole family to be able to communicate even in a crowded shopping mall. It gives everyone more freedom and peace of mind – and who couldn’t use more of that? |
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