What are some restrictions for MURS two-way radios?
Formerly in the business band, the FCC revised their regulations to add these 5 VHF frequencies to family radio. Since the end of 2000, users of the MURS band are not required to have a license.
However, there are a few restrictions. MURS two-way radios may not transmit above 2 watts and may not be used with a repeater-unless you got your license before they changed the rules, then you are grandfathered in and may continue to use repeaters and higher powered radios on this band. The MURS band comprises 5 frequencies between 151.820- 154.600 MHz, some of which include what are known to old school two-way radio enthusiasts as belonging to the "color-dot Series."
Businesses are permitted to use this license-free range of frequencies. However, the bandwidth is considered inside the VHF range. So, the communication will not be as effective as UHF radios when used indoors.
Narrowbanding: As more two-way radio users crowd the public air waves, the FCC must keep reworking their management strategies to make room for everyone on the frequency spectrum. The size of a channel available for a single voice path has been 25 kHz. To squeeze in more communications, the FCC now mandates that manufacturers must downsize channels to 12.5 kHz. Though there is no official deadline as of yet, the FCC is "strongly urging" business to look ahead and migrate to the very narrow band channel size of 6.25 kHz, which will likely be the future target of all radio bands.
Don't worry. Your gear isn't going to become obsolete overnight. If you bought your walkie-talkies from Motorola after 1997, your two-way radios are narrowbanding capable. You may just need to make some adjustments in programming. However, narrowbanding can be a factor in compatibility with older radios. You'll find lots of good information here: FCC Narrow Band Frequencies.
In short, if you have both older and newer model radios, you will want to make some easy adjustments. Generally, older radios had both narrow and wide band spacing. Change the bandwidth of your older model radios to the narrow band spacing. Next, program your new radios to match their narrow spacings. Doing this will allow older model radios to communicate with newer model radios and still follow current FCC guidelines. If you need assistance adjusting your older and newer model Motorola radios, please call our help desk at 800-448-6686.
If you are currently an FCC license holder, you'll want to check the registration on your license to see if your license covers the 12.5 kHz band. If it doesn't, you'll need to modify your license before the deadline. Narrowbanding applies to VHF and UHF frequencies but not to 900 MHz radios.
How do you determine compatibility between different two-way radios?
There are very few things you can say across the board on compatibility, as compatibility often comes down to make and model and frequency programming. However, one rule to keep in mind is that UHF radios will never work with VHF radios.
If you stick with UHF radios, you'll probably be able to communicate using different radio models. For instance, the Motorola CLS series, which are UHF radios, shares certain frequencies with other Motorola UHF radios. So, the CLS series can communicate with the new RDX models or older XTN models, as well as many other UHF models from Motorola and other manufacturers, as long as both sets of radios are tuned to the same, shared UHF frequency. Another rule is that 900 MHz radios only talk to other two-way radios using the 900 MHz technology.
Consumer-grade two-way radios built for the FRS, GMRS, and FRS/GMRS may communicate across manufacturers' brands because they often come pre-programmed to operate on the standard frequencies allotted to those radio services. For example, some radios come set to channel 1, code 1. If your new walkie-talkie won't talk to your old one, try setting them both to channel 1, code 0. Using the same channel number and privacy code might enable your two-way radios to talk to one another.
One reason compatibility can be an issue is that older radios can't understand or produce some of the same tones the newer radios use to talk to one another. With the more complex business radios, compatibility gets a bit more complicated; especially in the higher power 4- and 5-watt models.
If you're looking to buy a newer model that will work with your older business walkie-talkies, look for a model that uses the same frequencies. If your old radio was pre-programmed, was it programmed with custom frequencies? If so, it probably won't work with other radios out of the box, even if you choose the same model. So, your new radios should be programmed to match the old radios by your dealer. The dealer can program the radios using your frequency and privacy codes, which may be given to the dealer or the dealer can "read" an old radio to obtain that information. Manufacturers or two-way radio dealers' web pages are a great place to get information on compatibility. Check out www.techwholesale.com for clear, concise information on manufacturers and compatibility.