Applications for Intercom Systems, Wireless Intercoms, and Two-Way Radios

The UHF two way radio band for commercial radios is between 400 – 512 MHz.Until recently, it wasn’t widely used.Now, the UHF radio frequency is used for two-way radios, GPS, Bluetooth, cordless phones, and WiFi.

There are more available channels with UHF so in more populated areas UHF may be less likely to have interference from other systems.The range of UHF is also not as far as VHF under most conditions, but this reduced range may be a positive in some cases. Since UHF has lower range, there is less chance of distant radios interfering with your signal.

If you are in an area where population is thin, VHF should work fine for you. Not too long ago the FCC also opened up a new VHF frequency called MURS that is so far not heavily used in most areas. If you are in an area where interference from other radios may be an issue, UHF transmitters and receivers could be your best choice unless you use a MURS radio.

While VHF may be better at penetrating physical barriers like walls that doesn’t mean it will give you greater coverage in a building.The shorter wavelength of UHF means that it can find its way through more spaces in your building. In the walking around with a pole example above, the UHF signal has fewer obstacles that totally block it.

To highlight the differences in indoor range, below is an excerpt from a brochure of a leading two-way radio maker on the predicted range of one of their lines of handheld VHF and UHF two-way radios:

“Coverage estimates: At full power, line-of-sight, no obstructions the range is approximately 4+ miles. Indoor coverage at VHF is approximately 270,000 sq ft and 300,000 sq ft at UHF. Expect about 20 floors vertical coverage at VHF and up to 30 floors at UHF. Note: Range and coverage are estimates and are not guaranteed.”

The greater wavelength of VHF makes it more difficult for it to bounce its way through walls, buildings and rugged landscape.Therefore range will be reduced for VHF radios in these environments. That may not necessarily be a problem if the range needed is only a few hundred feet. You can also add an external antenna to an indoor VHF base station that will reduce or eliminate this problem.

One of the downsides to UHF is that the FCC requires you to get a license to operate in these frequencies, although many frequencies in the VHF business band also require a license. If you choose a radio in the VHF MURS frequencies you can operate it without a license.

One other advantage of the short wavelength that is produced by the higher UHF frequency is that the antenna on the radio can be shorter than an equivalent VHF radio. That can make it more convenient to carry around as a portable radio.

In summary, if you are planning on using your two-way radios mainly inside buildings, then UHF is likely the best solution for you, but it in lots of applications VHF could still work fine. If you are mainly using your two-way radios for communication outside, then VHF would be a good choice, unless the area you are covering is heavily wooded. Either radio technology can work for you if you don’t really have a long range to cover. There are also repeaters you can install that relay a UHF signal. We’ll talk about those in the Accessories section.

There is also an article about UHF Versus VHF by clicking the link in this sentence.

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