How to choose the best wireless intercom system for your home or business
Shopping Product ReviewsWhen you decide to add a new wireless intercom system to the ever-growing portfolio of wireless devices in your home or business, you should first think about compatibility with products you already have (or your close neighbors have). You should also consider the range and features you need.
Wireless Intercom Frequencies
In the United States there are several frequency ranges for wireless products for unlicensed consumer use. They are 49 MHz, 900 MHz, 2.4 GHz, 5.8 GHz, and the Family Radio Service (FRS) band. More recently, the FCC added the Multi-Purpose Radio Service (MURS). Radio frequencies for devices are similar in Canada, but MURS cannot be used there.
When consumer wireless products were first introduced, these wireless products used the 49 MHz frequency spectrum. Early cordless phones used this spectrum and it is still used by cheap baby monitors and other low-end wireless units. It has a short range and is prone to a lot of interference. You probably won’t find wireless intercom systems that use this spectrum anymore, or if you find them, you won’t want them.
Later, 900 MHz products using analog transmission technology came onto the market. Neither the 49 MHz nor these early 900 MHz products have any kind of security. Anyone with a device on the same frequency can listen in on the conversations. Newer 900 MHz digital spread spectrum products divide the digital transmission into a range of frequencies so that other devices cannot listen to your conversations. Spread spectrum digital intercoms also have a greater range than 900Mhz analog units. There are at least two wireless intercoms currently on the market, but only one of them uses digital spread spectrum. The wireless intercom system using spread spectrum can communicate up to 1000 feet.
2.4 GHz devices were next to the market. There is a growing number of cordless phones and other devices in this range. In terms of intercom systems, video door entry systems are the main users of this range, although the only wireless video door entry system on the market was recently discontinued. 2.4 GHz is also the frequency range used by WiFi (802.11B/G) wireless data networks in homes and businesses, so products in this range may interfere with each other.
The Family Radio Service (462-467MHz) is in the Ultra High Frequency (UHF) band and is basically an improvement on the old walkie talkies of yesteryear. These portable radios are sold everywhere and are widely used, so any intercom system in this range would have to compete with these portable radios (and anyone can listen in on your conversations). Wireless intercom systems using FRS are not known.
Now, 5.8 GHz products are beginning to make an appearance in the field of cordless phones. There are no compatibility issues between 5.8 GHz and 2.4 GHz devices, so there should be no problem mixing them. However, no wireless intercom systems are currently known in this range.
You will also see some intercom systems that claim to be wireless, but actually use the electrical wiring in your home or business to send and receive transmissions from the intercom. These are often called “FM wireless intercoms”, although they often transmit over your home’s wiring on the AM band. To use them, simply plug an AC adapter into the wall. These systems are very prone to buzzing or buzzing noises and are not recommended unless you are prepared to live with this possibility. Since the house wiring is 240 volts and splits into two 120 phases, you will also experience problems with the signal trying to cross the phases. One part of your home or business may function well while the other half does not. These intercoms are usually the least expensive intercoms of the bunch.
Long Range Wireless Intercoms
The most recent addition to the wireless intercom market are products in the MURS frequency range. MURS is a service in the 150 MHz VHF (Very High Frequency) radio spectrum. MURS has a power increase of four times that of FRS radio. And unlike FRS, you can add a larger or external antenna to improve range. If you want to put an antenna on top of your house, you can do it with MURS. Some antenna manufacturers claim that an external antenna can increase the effective radiated power of a transmitter by a factor of 4. These MURS intercoms can transmit up to four miles, and perhaps more with an external antenna.
The United States Federal Communications Commission (FCC) does not require you to obtain a license to use MURS frequencies, so you will not have to go through that process.
There are 5 MURS channels and 38 interference eliminators or “quiet codes” that can be used on each of these channels. These silence codes keep your radios silent unless another radio is programmed to the same channel and silence code. You most likely won’t have to worry about these codes, since MURS is extremely light to use. There are only a few manufacturers of MURS radios, so traffic on these frequencies is hard to find in most areas.
The MURS intercom system is the wireless intercom you need if you have a large property or need to talk between buildings. You can use a MURS not only to communicate within a house, but also with neighboring houses. You can even add a portable unit to your MURS intercom system to keep in touch outside of your home.
Long Range Outdoor Wireless Intercoms
You can also get commercial-grade wireless call boxes that communicate with two-way radios and base station intercoms. These cordless phone booths are waterproof and designed for outdoor use. They can remotely open gates or doors if you have a model with a gate relay. The mailboxes also come in vandal-proof housings with stainless steel front panels. The range of these is up to a mile or more if you use an external antenna. These cordless call boxes can be powered by batteries, an AC-DC converter, or solar power. Callboxes are available in both UHF and VHF frequencies so you can pair them with your existing two-way radios if you have them. You can get call boxes that work on the MURS frequencies without a license so you can use them with your MURS intercoms or radios.
The benefit of a cordless phone booth is that you save money by not having to dig trenches or run expensive wires to the unit. You also don’t have to pay any airtime or phone service charges with these wireless systems. Another benefit is that since the unit is wireless, the people monitoring the units can carry handheld radios that communicate with the call box. That allows your tracking people to be mobile.
Features of the wireless intercom
Another thing to consider is what features you need for your particular application. Business applications often need a wider variety of features. The MURS wireless system, for example, has a wide variety of products that can be used with it. Not only can you get military-grade two-way radios with many headset options, but you can also get base station intercoms, wireless call boxes with solar power option, wireless public address systems, customer service call boxes, remote switches wireless and movement. detector devices For less commercial or residential use, a 900 MHz intercom system has outdoor intercoms and doorbell intercoms that you can use with your indoor intercoms.
So the wireless intercom system you choose depends on the application you have, the wireless devices you already have in your home or business, the range you need to cover, and your budget. But once you choose the right system, you can enjoy the convenience of a wireless intercom system for years to come.