Interesting Facts About Cell Phones

Cell phone (telefone celular) is a wireless, portable, long-range, electronic telephone, which during travel can seamlessly change from one antenna connections, radio reception cell to another cell radio reception, without dropping or losing the ongoing call.

Interesting Facts About Cell Phones

Interesting Facts About Cell Phones

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Interesting Facts About Cell Phones

Interesting Facts About Cell Phones

Besides the standard voice function of a telephone, latest cell phones (telefone celular) have features such as SMS for text messages, MMS for multimedia messages, radio, games, internet connectivity for email, browsing, blogging, music (MP3) playback, memo recording, built-in cameras and Camcorders, ringtones, personal organizers, Push-to-Talk (PTT), infrared and Bluetooth connectivity, call registers, streaming video, downloading videos, video call, and also serves as wireless modems for PCs thatcan be connected to the Internet.

The power in a cell phone (telefone celular) is obtained from rechargeable batteries, which can be recharged from the mains, a USB port or a cigarette lighter port in an automobile. Nickel Metal Hydride were the most common types of batteries, which due to the "memory effect" (the user can recharge only when the enTire battery is drained off) were replaced by Lithium-Ion batteries, which did not suffer from any memory effect.

Cell phones (telefone celular) came into existence because of the invention of hexagonal cells in 1947, for the base stations by Bell Labs engineers at at & t. This was further developed during the 1960s by Bell Labs. During a call, the channel frequency could not be changed automatically from one cell (base stationcoverage area) to another cell (base station coverage area) as the person traveled from the area of one cell to the area of another cell. Amos Joel of Bell Labs invented a breakthrough invention and called it as the call handoff ' by which the channel frequency could be changed automatically from one cell to another cell, during the same call, as the mobile user traveled from one cell to another cell. Due to their heavy construction, these phones were used mainly in automobiles.

The first practical cell phone in a non-vehicle setting, and which could be handheld, was invented by Martin Cooper, the General Manager (Communications Division) of Motorola, who made the world's first handheld cell phone (telefone celular) call on April 3, 1973.

The technology bywhich the cell phone (telefone celular) works depends on the mobile phone operator; however, all of them use electromagnetic radio waves, which are in touch with a cell site (base station). The base station is composed of several antennas which are mounted on a pole, tower, or building. Cell sites are spread at a distance of 5 to 8 miles (approx. 8 to 13 miles) from each other. The low power transceiver from the cell phone transmits the voice and data to the nearest cell site. During moveMent, the cell phone will "handoff" the information to other cell site. Mobile phone operators use many technologies to maintain the smooth stream of digitized data from the cell phone to the cell site and vice versa.

The wireless telephone technologies are grouped under heads known asgenerations, starting from zero generation or 0 g. The current generation going on is 4 g; however, there are old cell phones (telefone celular) that still operate on 1 g, 2 g, and 3 g technologies. The wireless telephone technologies used in each generation are as given below:

0 g: PTT, MTS, IMTS, AMTS, OLT, MTD, Autotel/PALM, ARP
1 g: NMT, AMPS/TACS/ETACS, CDPD, Mobitex, Hicap, DataTac
2 g: GSM, iDEN, D-AMPS, IS-95/cdmaOne, PDC, PHS, CSD, HSCSD, GPRS, CDMA2000 1xRTT, WiDEN/IS-2000, EDGE (EGPRS)
3 g: W-CDMA, UMTS (3GSM), FOMA, TD-CDMA/UMTS-TDD, 1xEV-DO/IS-856, TD-SCDMA, GAN (UMA), HSDPA, HSUPA, HSPA, HSPA +, E-UTRA
4 g: UMB, UMTS Revision 8 (LTE), WiMAX
Frequency bands: SMR, Cellular, PCS

The impact of cell phone (telefone celular) usage on human health has been ofconsiderable worldwide concern. Research studies in Copenhagen, from the Danish Institute of Cancer Epidemiology, the National Cancer Institute, and the Institute of Cancer Research, do not establish any link between cancer and cell phone usage. However, an intergovernMental agency IARC (International Agency for Research on Cancer) forming part of the World Health Organization of the United Nations, undertook a study of 4.500 users and found a statistically significant link between cell phone usage and tumor frequency. Further research is going on.

Cell phone (telefone celular) usage and driving is a common worldwide phenoMenon. Some jurisdictions have banned usage of hand-held phones during driving, but allowed the hands-free fashion of cell phone usage while driving. However,studies have found out that the distraction is caused by the conversation itself; hence, both hand-held and hands-free cell phones contribute towards road traffic accidents. Further studies on cell phone usage and driving are going on.

Nokia Corporation is currently the world's largest manufacturer of cell phones (telefone celular). Other notable cell phone manufacturers, in alphabetical order, are 3 g, Audiovox (now UT Starcom), Benefon, BenQ-Siemens, Fujitsu, High Tech Computer Corporation (HTC), Kyocera, LG, Motorola, NEC, Panasonic (Matsushita Electric), Pantech, Philips, Research In Motion, Sagem, Samsung, Sanyo, Sharp, Siemens, Sierra Wireless, SK Teletech, Sony Ericsson, T & A Alcatel, Toshiba, and Verizon.

Interesting Facts About Cell Phones

Motorcycle Intercoms-How to Choose the Best Motorcycle Intercom For You

Without a motorcycle intercom, motorcycle riding is a solitary experience. When you're riding alone it's a good way to clear your head or get your thoughts together. But if you've got a passenger, or you're riding with another biker, inevitably you'll want to talk to them. Motorcycle intercom systems that mount in your helmet let you do that.

Motorcycle Intercoms-How to Choose the Best Motorcycle Intercom For You

Motorcycle Intercoms-How to Choose the Best Motorcycle Intercom For You

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Motorcycle Intercoms-How to Choose the Best Motorcycle Intercom For You

Motorcycle Intercoms-How to Choose the Best Motorcycle Intercom For You

The problem is that there are so many to choose from in such a wide price range. It's hard to decide which one to choose. And given that motorcycle intercoms have to work in an extremely difficult environMent, choosing the right one can make the difference between enjoying your new purchase or hating it. This motorcycle intercom review will hopefully make your decision easier.

Let's start with a broad overview of the types ofmotorcycle intercoms available.

Acoustic Motorcycle Intercom

The most basic form of motorcycle intercom is the acoustic intercom. By acoustic I mean that it doesn't use electronics at all. It just uses hollow tubes that your voice travels through. They're like the old ships where the captain yells down a tube to the engine room to tell them to "give it more steam."

These systems have rubber-tipped tubes that insert into your ear the same way an earPlug would. There is also a file:trumpet mouthpiece tube for you to talk into and all the tubes connect into a junction box.

One of the positives is that there are no batteries or electronics to mess with. That makes them very dependable. However, there is no amplification which means there is no way to adjust thevolume or Filter out wind noise. So at higher speeds, it will be more difficult to hear. Another problem is that some people find the "earPlugs" uncomfortable in their ears for long periods.

Obviously these acoustic intercoms only work for rider-to-passenger and bike-to-bike.

Wired Motorcycle Helmet Intercom

The next step up is wired intercoms. These systems have wires that run from the rider and passenger into a central control box that houses the electronics and battery.

Just like the acoustic, with a wired intercom system you don't have to worry about any external interference like you do with wireless technologies, unless you add a radio handheld communicator for bike-to-bike talking to your system. Some wired units let you Plug inan FRS/GMRS radio, which is described in the wireless technology section below. The radio requires voice activation for it to work.

One of the issues some people have is that the wiring can be a little bit of a pain. Every time you and a passenger get on and off the bike you have to remember to unplug the units. Depending on how you have it set up, this could be two or three plugs.

Wireless Intercom Technology

There are four types of radio technologies used in the U.S. for motorcycle intercoms. They are GMRS, FRS, FM, and Bluetooth. There are also wired intercoms that enable you to plug into a handheld Citizens Band (CB) radio that has voice activation.

Frequency Modulation (FM) radio is similar tothe FM radio you listen to, but for motorcycle intercoms to narrower frequency is used. Like FM radio, these systems can produce clear sound, as long as the distance between them isn't too great. FM radio works best when there are no obstructions such as hills between the transmitter and receiver. If long range is the most important feature, then GMRS intercoms will provide better performance.

The Family Radio Service (FRS) and General Mobile Radio Service (GMRS) are the modern equivalents to the old walkie talkies you may have had when you were a kid. FRS radios typically have a maximum range of two miles with few obstructions in between, while GRMS radios communicate up to several miles. Like FM, these are publicfrequencies so other people can hear your conversations and vice versa. In some heavily populated areas these FRS/GRMS radios are heavily used, while out on the open road you should have fAirly private conversations.

One nice thing with the FRS and GMRS radios is that you can go to your local discount store and purchase a cheap handheld radio that will communicate with these units. If someone were following you in a car, or they had a wired motorcycle helmet intercom system that lets them plug in an FRS/GMRS handheld radio, they can communicate with you. The downside of this was just Mentioned in that there are millions of these radios out there so in heavily populated areas you'll pick up lots of other transmissions. Also GMRS> radios require an FCC license for legal use.

Bluetooth is the latest technology to hit motorcycle intercoms. Not only can these systems communicate totally wirelessly from rider to passenger, they can be used to communicate from bike to bike. Although with these systems the range is not in miles, it is in hundreds of feet. Since you are likely riding close to your buddies, this is not usually a problem. Although, the range can be as much as 800 to 1600 feet.

The Bluetooth range limitation actually works as an advanTAGe since it limits the amount of outside interference you'll get. Also, since you must program two units to work together, you won't pick up conversations from other people with Bluetooth devices ... and they won't be able to hear you. You won't have to worry aboutyour conversations listened to by anyone else.

If you want Bluetooth wireless communication there is one thing to Watch for. Some units that say they are use FRS or GMRS Bluetooth to communicate bike-to-bike and the Bluetooth is just used to communicate with a Bluetooth enabled cell phone or other device.

Bluetooth intercoms also usually have some other features you won't find on other types of intercoms such as:
Integrated with Bluetooth enabled cell phones and automatically answer calls completely hands free. Enjoy your favorite music from your stereo A2DP enabled cell phone or MP3 player Listen to the audio navigation message from your Bluetooth enabled GPS.

Some Bluetooth intercoms only have one ear Speaker while others have two.

MotorcycleHelmet Intercom Features

Here are features to look for as you are shopping for an intercom to use with your motorcycle helmet:
If you may be riding in the rain, get a system that says it's waterproof and not just water resistant. Some riders will put a water resistant system in a plastic baggie and that works for them. You can get systems that have a headset Speaker for one ear or both ears. Installation and moving the intercom to another helmet is easier for systems with only one ear, but some people want to hear sound in both ears. Most systems have voice activation of some kind to keep the headset quiet when no talking is occurring. This voice activation often has the ability to be disabled and a push-to-talk switch is used instead. Many intercoms have noisereduction capabilities with digital signal processing to help reduce the noise they pick up from the microphone. The Faster you drive, or the windier it is, the more important this feature is. If you want music, look for a system that has a built-in FM stereo radio tuner or an auxiliary stereo input for a Walkman, MP3, iPod, satellite or radio unit. You can also use this input to receive driving directions from a GPS unit yesterday prompted voice. Some systems mount on your helmet, while others have capability to mount on your belt clip or bike. If the system is big and bulky, you may want the ability to mount it on your bike. You can integrate some intercoms with cell phones so you can talk while you ride. They require special cables or you can get motorcycle intercomsthat have Bluetooth capability so they connect to your Bluetooth-enabled phone wirelessly.

Once you find the right motorcycle intercom for you, it will really make your ride with other people much more enjoyable. You'll wonder how you got along without it. You typically get what you pay for when you buy motorcycle intercoms, but even a bad motorcycle intercom is better than none at all.

Motorcycle Intercoms-How to Choose the Best Motorcycle Intercom For You

How To Find The Best Marine GPS For Your Boat

To find the best marine gps, you have to do a lot of comparison shopping and reading about the different brands before making an informed decision. Do some comparison shopping, read the many reviews, and shop around a little bit before making up your mind which is the best marine gps navigational receiver for your needs. A marine gps navigational unit needs to use at least 12 of the 24 satellites calculating your position. All 24 would be the best, of course. And a larger screen for reading and viewing the water below the boat would be ideal. Some of the smaller, handheld or portable marine gps units are not the best because the size takes away from the clarity of the picture. There are several that are up to 7 "with a crystal clear Lcd touchscreen so you are able todistinguish a rock from a Fish when looking at the water or "bottom of the lake or ocean.

Another item to consider when hunting for the best marine gps would be the amount of alarms it has on it. Some have alarms for the clock, off-course, anchor drag, too shallow, too deep, proximity, low battery, arrival, waypoint, water temperature and temperature rate of change and there are others, but the best marine gps would have all the alarms for safety reasons. Along with the alarms, one must consider the nightWatch and sunlight modes many of the best marine gps units use to help with the glare from the sun off the water or to help you find your way back in the darkness of the night.

How To Find The Best Marine GPS For Your Boat

How To Find The Best Marine GPS For Your Boat

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How To Find The Best Marine GPS For Your Boat

How To Find The Best Marine GPS For Your Boat

You will need to decide if you are going to purchase a small, handheld or portable model or alarger, ' stay put ' type model of marine gps unit. The portable marine gps navigational units are smaller and fit in a pocket or a purse. However some of the bigger units can be taken out and used in a vehicle such as an RV or a car, but the portable ones are made for walking, hiking, biking and moving about the city with easy. Both styles of marine gps receivers come with the same amount of software and options, it just depends on which you prefer to have outside of the boat.

Do you want to be entertained? Some of the marine gps navigational units come with an audio voice player to play books on tape, others, you have to purchase a subscription to something like XM radio or a weather channel, which is not a bad idea since the weather changes rapidly and you want to be on topof things when the weather starts to change.

Above all, make sure the best marine gps unit has enough software to accommodate all you want to do while out in the boat, such as find Fish or avoid large chucks of debris. "These things can be done and avoided by the type of software available to download or that has already been downloaded into the marine gps unit. Do you have to purchase more antennas? Or extra cords for your Computer to be compatible? These are questions you need to ask yourself and the salesperson behind the counter or on the other end of the website.

How To Find The Best Marine GPS For Your Boat

Common Fuji Digital Camera Problems and Troubleshooting

If you own a Fuji digital camera, you must have bought it due to the fact that the product with such an established name is trustworthy. But even the most advanced cameras encounter problems now and then. However, do you know what to do about your Fuji digital camera problems? There are a few ways to determine and eliminate common Fuji digital camera problems, and the following information can be very helpful for that.

Common Fuji Digital Camera Problems and Troubleshooting

Common Fuji Digital Camera Problems and Troubleshooting

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Common Fuji Digital Camera Problems and Troubleshooting

Common Fuji Digital Camera Problems and Troubleshooting

When we talk of Fuji digital camera problems, we are talking about common problems that can hinder your ability to use your Fuji digital camera properly. Let's exclude such problems as breakage or water damage. These things are not the fault of the Fuji Company, and such damage might be hard to repAir unless your warranty covers such things. Common Fujidigital camera problems include such things as a dark screen, an out of focus picture, or any other Fuji digital camera problems that can be helped by customer service or with merely a little information on your particular model.

Of course, the first thing you should do in case of any Fuji digital camera problems is to call the customer service line that you can find in the docuMentation accompanying your camera. The customer service representative should be able to determine if your problems can be fixed over the phone and then will walk you through the steps to fixing them. However, if your Fuji digital camera problems can't be fixed over the phone, usually the customer service rep will provide you with steps for either sending your camera in to get it fixed, or for taking it to adealer to have it fixed. Either way, a customer service rep is a great way to find the solutions to your particular Fuji digital camera problems.

Another alternative is to carry out an internet search highlighting the problems you are having. Nowadays, it is really possible to get access to troubleshooting technology via online. Merely type the model number of the camera you own and what problems you are having. Most likely, someone else has had that same problem and so you should be able to find step by step instructions on how to remedy the problem with your camera. Just make sure that any steps you take are not against the warranty deal you have with the manufacturer (such as opening the camera up). Apart from that, the Internet can be of a great help in fixing your Fuji digitalroom problems.

With different choices available you should be able to fix any Fuji digital camera problems and soon be back to taking wonderful pictures with your Fuji digital camera.

Common Fuji Digital Camera Problems and Troubleshooting

An Introduction to Cell Phones

What are Cell Phones?

An Introduction to Cell Phones

An Introduction to Cell Phones

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An Introduction to Cell Phones

An Introduction to Cell Phones

Cell phones, also known as mobile phones or wireless phones, hand-held phones with built-in antennas. Unlike home phones, cell phones can be carried from place to place with a minimum of fuss. This makes them a good choice for people who want to be in touch with other people even when they are away from the house.

How Do Cell Phones Work?

An Introduction to Cell Phones

Polar Satellites

Geostationary satellites are generally placed at an altitude of about 36.000 km. But polar satellites are generally positioned at an altitude of about 850 km, so that they circle the earth every 100 minutes or so.

Polar Satellites

Polar Satellites

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Polar Satellites

Polar Satellites

The first polar satellite was launched on February 24, 1996 by national aeronautic and space administration (NASA). This was the second satellite to be launched under the global geospace science project. TIDE/PSI investigation is an important function of the polar satellite.

The main purpose of a polar satellite is to collect information on radiation and other atmospheric dangers. When a satellite flies in the upper atmosphere, there are chances that the satellite's instruMents can be damaged by sun's harmful radiation.

Polar Satellites

UHF Versus VHF-Which two-way Radio Frequency is Better?

There are two major formats for two-way radios. They are Ultra High Frequency (UHF) radio and Very High Frequency (VHF) radio. Neither frequency band is inherently better than the other. They each have their pluses and minuses. Both formats are effective ways to communicate with another person. But how do you decide which one will fit your needs? Let's go over the key components of both frequencies to help you decide.

UHF Versus VHF-Which two-way Radio Frequency is Better?

UHF Versus VHF-Which two-way Radio Frequency is Better?

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UHF Versus VHF-Which two-way Radio Frequency is Better?

UHF Versus VHF-Which two-way Radio Frequency is Better?

Two-way radios communicate with each other through use of radio waves. Radio waves have different frequencies, and by tuning a radio receiver to a specific frequency you can pick up a specific signal.

Radio waves are transmitted as a series of cycles, one after the other. You will always seethe "Hz" abbreviation used to indicate the frequency of a radio. Hertz is equal to one cycle per second.

Radio waves are measured by kilohertz (kHz), which is equal to 1000 cycles per second, or megahertz (MHz), which is equal to 1.000 .000 cycles per second--or 1000 kHz. The relationship between these units is like this: 1.000 .000 Hertz = 1000 kilohertz = 1 megahertz.

You may also hear the term "wavelength" when you hear about radio waves. This term is from the early days of radio when frequencies were measured in terms of the distance between the peaks of two consecutive cycles of a radio wave instead of the number of cycles per second. Lower frequencies produces a longer wavelength.

While wavelength measures distance between thepeaks of cycles, frequency refers to how long the measured time is between the "crest" and "trough" of a wave arriving at the source. So frequency measures time instead of distance, but they are essentially both saying the same thing.

What is significant about wavelength for two-way radios is that it affects transmission range under certain conditions. A longer wavelength as a general rule lets radio signal to travel a greater distance.

Lower frequencies or wavelengths have greater penetrating power. That's one of the reasons they are used for communicating with submarines. VLF radio waves (3-30 kHz) can penetrate sea water to a depth of approximately 20 Meters. So a submarine at shallow depth can use these frequencies.

So from what you read aboveyou may think VHF is always the better choice for a two-way radio no matter where you are using it. That's not necessarily true. Even though VHF has better penetrating capabilities, that doesn't necessarily make it the better choice for buildings. Remember the conversation about wavelength above? Wavelength has a big impact on transmission.

To explain this let's assume we are communicating from one side of a commercial building to the other. In between these two points is a metal wall with a three foot door in it. Metal is an enemy to radio waves and they typically don't pass through it.

For our example let's assume that the wavelength the UHF radio uses is about a foot and a half long and a similar VHF radio is around five feet long. These arein the ballpark of their normal wavelengths.

When the UHF transmits its signal the foot and a half long wave will pass through the door since the door is wider than the wavelength. The VHF signal will be totally reflected since it is wider than the opening to the door.

Your microwave oven is an example of this. The glass front door has a metal mesh with very small holes. Microwaves being a very high frequency have wavelengths that are only several inches long. The mesh keeps the microwaves trapped in the oven but it allows you to see inside because light waves have a wavelength microscopic.

Just imagine walking through the building carrying a five foot wide pole. You will encounter the same challenges to VHF signal encounters. Now imagine walking through the building witha pole that's only a foot and a half wide like a UHF wave. There are lots fewer doorways you couldn't get through.

The one difference is that wireless signals will penetrate through drywall, masonry, human bodies, furniture, wall paneling, and other solid objects. All these objects will reduce the signal strength though. The more dense the object, the more it reduces the signal. VHF will penetrate these obstacles better than UHF, but that doesn't necessarily mean that VHF is better for indoor applications as we will talk about in the UHF section below.

In our example above we assumed you had a metal wall with an opening. If you reverse this and you have a three foot metal object in front of the transmitting radio, then VHF would win. Since the object is three foot wideit will totally block the UHF signal whereas the VHF signal will get around it. Lower frequencies diffract around such as VHF large smooth obstacles more easily, and they also travel more easily through brick and stone.

For most applications, lower radio frequencies are better for longer range. A broadcasting TV station illustrates this. A typical VHF station operates at about 100.000 watts and has a coverage radius range of about 60 miles. A UHF station with a 60-mile coverage radius requires transmitting at 3.000 .000 watts.

So there is no clear choice for which is better, VHF or UHF. There is a lot of "black magic" to radio technology so it's not always easy to tell which will work better for your application. To help you decide on the best technology foryou, more detail about each one is included below.

UHF Radio

UHF equipMent operates between the frequencies of 300 MHz and 3000 MHz. Until recently, it wasn't widely used. Now, the UHF radio frequency is used for 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. 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. There's more about MURS below in the VHF section. If you are in an area where interference from other radios may be an issue, UHF transmitters and receivers couldbe your best choice unless you use a MURS VHF radio. UHF is better at squeezing through physical barriers like walls, buildings, and rugged landscape. Anything that obstructs a radio wave, will weaken a radio signal. UHF lessens that effect. Though it may not travel as far, UHF radio waves will traverse around obstacles better than VHF.

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. Expectabout 20 floors vertical coverage at VHF and up to 30 floors at UHF. Note: Range and coverage are estimates and are not guaranteed. "

VHF RADIO waves are not very good at finding their way around walls, buildings and rugged landscape. Therefore range will be significantly 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 on these frequencies. Although many frequencies in the VHF band also require a business license. If you choose a radio in the VHF MURS frequencies you can operate it without alicense. UHF equipment is usually more expensive. The components need to be finely tuned and are more expensive to construct. This does not mean it's necessarily better, just more expensive.

One advanTAGe of UHF transmission is the physically short wave that is produced by the high frequency. That means the antenna on the radio can be shorter than an equivalent VHF radio.

VHF Radio

VHF equipment operates between the frequencies of 30 MHz and 300 MHz. FM radios, two-way radios, and television broadcasts operate in this range.

Both UHF and VHF radios are prone to line of sight, but factors VHF a little more so. The waves make it through trees and rugged landscapes, but not as well as UHF frequencies do. However,if a wave and a VHF UHF wave were transmitted over an area without barriers, the VHF wave would travel almost twice as far. This makes VHF easier to broadcast over a long range. If you are working mostly outdoors, a VHF radio is probably the best choice, especially if you are using a base station radio indoors and you add the external antenna.

Since VHF has been around longer and isn't as complicated to make, equipment is usually cheaper when compared to similar UHF equipment. One disadvanTAGe to this equipment can be its size. Since the frequency waves are bigger, an antenna must be bigger.

VHF radios also have a smaller number of available frequencies. Interference with other radios could be more likely to be a problem. However, the FCCrecently made this less of a problem when they opened up the MURS frequencies. The 150 MHz frequency is a Citizens Band radio spectrum that is called the MURS service. MURS stands for multi-use Radio Service. This service is for use in the United States and Canada. It is a low power, short range service in the VHF 150 MHz Citizens Band radio spectrum. There are 5 channels in the MURS frequencies with 38 privacy codes under each one that enable you to only pick up conversations on your code. The FCC does not require users of products for MURS to be licensed.

With MURS, you can add a larger or external antenna to improve range. If you want to put an antenna on top of your house or business, you can do it with MURS. Some manufacturers claim an external antennaantenna 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 depending on the terrain.

One benefit of VHF wireless radios is that battery life is almost always better than for similar UHF units. For handheld radios this is a plus.

VHF equipment is usually lower cost for those on a budget. Equipment can be more economical than similar UHF products.

UHF Versus VHF-Which two-way Radio Frequency is Better?