Frequency Considerations for Recreational 2 Way Radios
If you are in the market for 2 way radios for personal use, you have an immediate and important choice to make: What radio frequency band do you require?
Frequency! 2 way radios obviously utilize 'wireless' communication methods so when using a 2 way radio you are transmitting and sending your message through the air -- the same air that is currently carrying television signals, commercial radio signals, Ham radio signals and literally thousands of signals from other private 2 way radios. The Federal Communications Commission (FCC) has the job of controlling all of these communication signals so they don't run into each other; to accomplish this they have reserved frequency bands for use by certain types of communication (signal sending) devices. There are two frequency bands in use for recreational 2 way radios, these are called Family Radio Service (FRS) and General Mobile Radio Service (GMRS).
In 1996, the FCC reserved a set of radio frequencies they called the Family Radio Service (FRS) band, specifically for short-range 2 way radios (radios that operate no more than 2 miles away from each other) with a small power output (up to 500 milliwatts or one-half watt).
About fifty years before the FCC created the FRS band they had reserved a set of frequencies for higher power 2 way radios that operated over a longer range this is the General Mobile Radio Service (GMRS) band. The GMRS band is for radios with a power output between one and five watts and a range over 2 miles. The FCC regulates the 2 way radios that operate on the GMRS band and requires users of this type of radio to obtain a license and pay a fee. The GMRS license is good for five years and costs $80.00; the license must be obtained by an adult (the radios operating under the license may be used by minors but only with the licensed adult's knowledge and permission). Go to the FCC's Internet page at: http://wireless.fcc.gov/services/index.htm?job=service_home&id=general_mobile
for more information on GMRS licensing.
When buying 2 way radios, your choice is between a set of radios that operates only on one of these frequency bands or a set of radios that is able to operate on either one of these frequency bands. This determination will obviously have to be made based on the maximum distance the radio users will be from each other. If the radios are to be used within two miles of each other, FRS will be the best (and least expensive) choice. If a greater distance is consistently required, 2 way radios that operate on the GMRS frequency band will be required. If the need for distance is uncertain or if you want the option of occasionally transmitting up to five miles a FRS/GMRS hybrid is the radio set to choose.
Showing posts with label radio. Show all posts
Showing posts with label radio. Show all posts
Wednesday, January 7, 2009
Tuesday, December 30, 2008
A Brief History Of The Radio
It is expect that nearly every household in the United States has at least one radio. The invention of the radio was dependent upon two previous discoveries: the electromagnet and telegraph.
The electromagnet was discovered in 1825. This discovery opened the doors to global communication! Five years later, Joseph Henry successfully transmitted an electric current via wire which was stretched over a mile and which caused an electromagnet to trigger the sounding of a bell. Thus, the electric telegraph was born. One of the most recognizable names associated with the telegraph is Samuel Morse who is most notable for the series of dots (brief sound) and dashes (more sustained sound) which was used to transmit messages by alphabet code (thus known as Morse Code). Telegraph became the sole means of rapid long distance communication until 1877 and the invention of the telephone.
Batteries are interesting, aren`t they? Used by the general consumer, they are small, but powerfully packed instruments which produce power used for many cameras, alarm clocks, radios, and other devices. What makes this power production possible? In the case of the telephone and it`s early design and use, batteries produced the essential source of power for the electromagnet.
Batteries have two ends to which one is assigned a `+` or positive, and the other a `-` or negative. When a battery operated device is switched on, the electrons which are produced by the batteries, quickly move from the negative side to the positive side of the batteries. Something was needed to interrupt this rapid flow of electrons or find the batteries totally expended in a brief time. In order to accomplish this, a wire is often inserted between the positive and negative terminals and a `load`, such as a radio, creating a small magnetic field in the wire. The electromagnetic waves which are present now, have the capability to transmit sounds (speech, music, and so on) as well as visual images undetected by sight through the air.
There are several scientists who must be mentioned as essential to the telephone as it is known to most of us. Mahlon Loomis created wireless telegraph. Guglielmo Marconi, proved the possibility of radio communication. In 1985 Marconi, transmitted and received a radio signal. Using the Morse alphabet, he sent the first wireless signal which was transmitted across the English Channel and in due time, he was able to receive the Morse letter S which began in England and reached Newfoundland which became the beginning of transatlantic radiotelegraphy (1902).
Wireless signals gained far reaching use as a means of communication for rescue work when an accident or disaster occurred at sea. In 1899 the United States Army began utilize wireless communication which originated from a lightship off Fire Island. The US Navy was about two years behind the Army in utilizing wireless telegraphy.
In 1903, President Roosevelt (Theodore) and King Edward VII communicated via this new and improving technology. The well known Robert Perry, using radiotelegraphy, conveyed the message that he had `found the Pole`.
The first AM radio entered the world of telecommunication in the early 1900`s. This device made the use of somewhat weak waves possible for communication. This was the time when the term `radio`, as we know today for radio devices, began to be used.
It is believed that in December 23, 1900, professor Reginald Aubrey Fessenden was the first person to successfully transmit human voice by radio waves. By 1915, speech was first sent across the United States beginning in New York City and sent to San Francisco. Somewhat later, transmission occurred across the Atlantic Ocean from Arlington, Virginia, to Paris at the Eiffel Tower.
It is truly fascinating all the scientists and the physics theories that led to the invention of the radio. Marconi, Alexander Popov, Oliver Lodge, Fessenden and many others, have all made important contributions to an invention that made the world so different, that most likely none of them would envision. The radio era was born.
The electromagnet was discovered in 1825. This discovery opened the doors to global communication! Five years later, Joseph Henry successfully transmitted an electric current via wire which was stretched over a mile and which caused an electromagnet to trigger the sounding of a bell. Thus, the electric telegraph was born. One of the most recognizable names associated with the telegraph is Samuel Morse who is most notable for the series of dots (brief sound) and dashes (more sustained sound) which was used to transmit messages by alphabet code (thus known as Morse Code). Telegraph became the sole means of rapid long distance communication until 1877 and the invention of the telephone.
Batteries are interesting, aren`t they? Used by the general consumer, they are small, but powerfully packed instruments which produce power used for many cameras, alarm clocks, radios, and other devices. What makes this power production possible? In the case of the telephone and it`s early design and use, batteries produced the essential source of power for the electromagnet.
Batteries have two ends to which one is assigned a `+` or positive, and the other a `-` or negative. When a battery operated device is switched on, the electrons which are produced by the batteries, quickly move from the negative side to the positive side of the batteries. Something was needed to interrupt this rapid flow of electrons or find the batteries totally expended in a brief time. In order to accomplish this, a wire is often inserted between the positive and negative terminals and a `load`, such as a radio, creating a small magnetic field in the wire. The electromagnetic waves which are present now, have the capability to transmit sounds (speech, music, and so on) as well as visual images undetected by sight through the air.
There are several scientists who must be mentioned as essential to the telephone as it is known to most of us. Mahlon Loomis created wireless telegraph. Guglielmo Marconi, proved the possibility of radio communication. In 1985 Marconi, transmitted and received a radio signal. Using the Morse alphabet, he sent the first wireless signal which was transmitted across the English Channel and in due time, he was able to receive the Morse letter S which began in England and reached Newfoundland which became the beginning of transatlantic radiotelegraphy (1902).
Wireless signals gained far reaching use as a means of communication for rescue work when an accident or disaster occurred at sea. In 1899 the United States Army began utilize wireless communication which originated from a lightship off Fire Island. The US Navy was about two years behind the Army in utilizing wireless telegraphy.
In 1903, President Roosevelt (Theodore) and King Edward VII communicated via this new and improving technology. The well known Robert Perry, using radiotelegraphy, conveyed the message that he had `found the Pole`.
The first AM radio entered the world of telecommunication in the early 1900`s. This device made the use of somewhat weak waves possible for communication. This was the time when the term `radio`, as we know today for radio devices, began to be used.
It is believed that in December 23, 1900, professor Reginald Aubrey Fessenden was the first person to successfully transmit human voice by radio waves. By 1915, speech was first sent across the United States beginning in New York City and sent to San Francisco. Somewhat later, transmission occurred across the Atlantic Ocean from Arlington, Virginia, to Paris at the Eiffel Tower.
It is truly fascinating all the scientists and the physics theories that led to the invention of the radio. Marconi, Alexander Popov, Oliver Lodge, Fessenden and many others, have all made important contributions to an invention that made the world so different, that most likely none of them would envision. The radio era was born.
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