Radio Communication with First Responders Pending at Lenape Tech

While many of my readers are excited about some of my own articles, here’s one i found looking around tumblr.com it is far better written than I could ever expect to reach. Maybe one day I’ll get to their level, you never know.

Two-way radio communication at a local technical school would greatly improve school security, according to one local official.

Lenape Technical School Special Programs Coordinator Carla Thimons further explained the need for such during discussion on the Manor Township school’s $18,000 Pennsylvania Department of Education Safe School Initiative Competitive Targeted Grant award.

“These will truly help us feel better about safety overall, because communication is key,” Thimons said.

She said several programs at the technical school provide a unique challenge where areas of the building would not be able to listen to announcements over the public address system, and the radios would provide necessary internal communication with teachers and staff.

Thimons said the grant funds were accepted by the Joint Operating Committee last month, and funding received, but the radios have not been purchased yet. She explained officials want to coordinate efforts with the Armstrong County Department of Public Safety to ensure that communication will be loud-and-clear.

“We want to determine the best purchase,” Thimons said. “We have an idea in mind what we want, but we want to coordinate with (the Department of Public Safety.)”

Radios are to be expected to be carried in the school hallways by officials by the start of the 2014-15 school year.

Thimons, who has been Special Programs Coordinator for 10 years and was previously the technical school’s principal, coordinates special education, grant writing and safety procedures at the school.

Besides the two-way radios, Thimons said school officials are planning to hold school wide drills, including a mass-evacuation drill.

Joint Operating Committee members also unanimously approved the hire of Night Watchman Samantha Walker, retroactive to March 7.

Principal Karen Brock last month said the school used to have night watchmen, but another one needed to be hired to replace that individual.

Armstrong School District also received Safe School Initiative Competitive Targeted Grant funding in the amount of $25,000, and put the money toward the purchase of new and updated security cameras “as another layer of security throughout the district,” according to School Superintendent Stan Chapp in March.
Director of Technology and Information Services Anthony Grenda said about 16 surveillance cameras will be added to the interior and exterior of Elderton and Shannock Valley Elementary Schools. He hopes those cameras are installed by the end of the current school year. Several have already been installed, he said earlier this week.
Apollo-Ridge and Leechburg Area School Districts also received $25,000 in grant funds.
Earlier this year, Armstrong also received $40,000 in the state’s Safe Schools Grant Program for utilization of a school police officer. Those officers have also been already utilized throughout the district.
The Lenape Tech Joint Operating Committee meets again Thursday evening, beginning with a 6:30PM public budget session at the school.

Source – http://www.kittanningpaper.com/2014/04/16/radio-communication-with-first-responders-pending-at-lenape-tech/44954

 

DMR Tier III: the open standard for radio communications

When we found this post we were so pleased, having searched for over one year for this, finding it on this website was an thrilling time for me.

Private mobile radio is fast becoming an essential communications solution to support the operational needs of utilities companies, airports, oil and gas pipelines and emergency services.

When compared to public cellular services, it delivers improved coverage, reliability and resistance, contention, security, group communications and performance.

The digital landscape is crowded, though, with a number of public safety digital standards such as TETRA, P25 as well as low cost digital solutions including DMR (Digital Mobile Radio), dPMR (digital Private Mobile Radio), NXDN and PDT (Professional Digital Trunking).

DMR is coming out on top thanks to the open standard nature of DMR Tier III trunking, which is driving its emergence, ongoing development and adoption across global markets.

But do open standards matter? While open standards are less important in the small system market, they are critical to the long-term case for the radio system in the medium to large systems sector, and it is here that open standard DMR Tier III will dominate.

Essentially, DMR Tier III trunking features a control channel on each radio site and allocates traffic channels on demand making it frequency efficient and enabling a large number of users to share a relatively small number of channels. Radio sites can easily be inter-connected, usually using IP connections, making it possible to deploy systems ranging from a single site to hundreds of sites spread over a large geographical area.

The open standard way

The DMR standard includes the facility for implementers to provide ‘manufacturer extensions’, enabling manufacturers to provide proprietary features within the framework of the DMR air interface definition. This allows them to complement the standard set of DMR call functions with their specific facilities.

This has the advantage of enabling customers to request specific functionalities to support the manufacturer’s business operation needs and also enables them to provide innovative features that differentiate their solutions from others implementing the same standard.

One disadvantage to this offering is that interoperability can only be possible for those features that are fully defined by the standard and that customers using manufacturer extensions are effectively locked in to a single manufacturer solution rather than enjoying the vendor choice that a standard enables.

To address the pros and cons, the DMR Association (DMRA) has struck a balance between robustness and cost with their interoperability process, which focuses on testing the conformance of products against the published standard that describes the over-air signalling. The DMRA facilitates testing between a terminal manufacturer and an infrastructure manufacturer, and the two parties carry out the testing against a standard test specification. Test results and logs of all messages sent over air are recorded during the testing and then are inspected by one or more independent third parties during a detailed review meeting. Only after the independent third parties are satisfied that the equipment under test has conformed to the open standard specification is an interoperability certificate issued.

Ongoing standards development

Whilst this facility can be useful, extensive use of manufacturer extensions would call into question whether DMR was a standard that delivers interoperability (and therefore vendor choice) or whether it results in proprietary solutions rather than following an open standard.

The answer to this lies in the work of the DMR Association. The DMRA has a technical working group – made up of competing manufacturers – who collaborate to ensure the standard succeeds. Any proprietary features from the manufacturers, which are believed to have wide market appeal or have useful features the standard doesn’t yet specify, are debated in the group. They are then developed to further advance the standard to the benefit all of the manufacturers and indeed the customers who choose to implement DMR technology.

The DMRA is further developing the standard to meet future market demands by identifying important new features and ensuring these are developed and included in new releases of the ETSI standards.

The future of DMR Tier III

Open standards are critical to providing long-term support and stability to customers. The adoption of the standard by a critical mass ensures its longevity over other similar competing technologies that have lower levels of support by offering the market vendor choice and maintaining low costs.

Is DMR Tier III radio communications’ open standard for the future? Yes. Due to DMRA’s authority, the robust and well-supported interoperability programme and the long-term commitment of a large number of manufacturers, it is emerging as the most successful low cost digital technology for complex projects – and therefore the open standard that no other private mobile radios can contend with.

Source – http://www.telecomstechnews.com/news/2014/apr/25/dmr-tier-iii-open-standard-radio-communications/

Inventors That Changed the World: Al Gross

Much like Arnold Schwarzenegger’s character in the movie ‘Twins’, the walkie-talkie can claim to have many fathers. However, one of the most prominent names in the debate (and maybe the one with the single strongest claim to having invented the walkie-talkie) is Canadian/American inventor Al Gross.

The son of Romanian immigrants, Al Gross was born in Toronto, Canada in 1918, but his parents moved to Cleveland, Ohio, USA when he was quite young. Whilst on a steamboat trip across Lake Erie, the 9-year-old Gross encountered radio technology for the first time and, in so doing, ignited a passion within him that would change the world.

How passionate was he? By age 12, Gross had turned his parents’ basement into a radio centre. The bright young man would visit junkyards and salvage any material he thought he could use. Four years later –aged 16- Gross was awarded an amateur radio license, which was still in effect at the time of his death in 2000.

At the age of 18, Gross enrolled in the Case School of Applied Sciences. At the time, radio frequencies above 100MHz were relatively unexplored territory. Gross wanted to see exactly what could be done with them. He wanted to create a mobile, lightweight, handheld transceiver, using those uncharted frequencies. In 1938, he did just that, patenting the two-way radio, or ‘walkie-talkie’. He was just 20 years old.

War arrived on American shores in 1941 with the attack on Pearl Harbour. America scrambled to mobilize its armed forces and take advantage of any/all new technology that could aid the struggle against the Axis powers. The US Office of Strategic Services (OSS) – a forerunner to the CIA – tapped Gross to create an air-to-ground communications’ system. The system Gross designed employed Hertzian radio waves and was almost impossible for the enemy to monitor, even when allied planes were in enemy airspace. Gross’ system proved incredibly successful (so much so, that it was not declassified until 1976).

After the war, the inventor turned entrepreneur and founded the Citizens Radio Corporation, which took advantage of the first frequencies designated for personal use. His company was the first to receive FCC approval for use with the new ‘citizens’ band’. He licensed radios to other companies and supplied units to the Coast Guard, amongst others.

Then, in 1949 came another amazing discovery. Gross invented and patented the telephone pager. He invented the system with doctors in mind, but the medical community was (amazingly) slow to respond to this new technology. Only New York’s Jewish Hospital saw the potential of the pager as a life-saving device, when they implemented it in 1950.

Throughout the 1950’s, Gross, ever the pioneer, fought hard to garner interest for his newest idea – a mobile telephone. It took him eight years to get mobile telephony, as a concept, off the ground. Talk about being ahead of the curve!

Unfortunately, many of Gross’ best ideas were so far ahead of said curve, that his patents ran out before he could garner the profit his genius deserved. Had he earned the money eventually generated by CB radio, pagers and cellular phones, he would have died an extremely rich man. However, it was not to be.

Gross invented a lot throughout the years, but nothing brought him the amount of money that he potentially could have made from his earlier inventions. However, Gross was able to make a comfortable living, spending the 1960’s working for large corporations as a specialist in communications systems. 

In the 1990’s, he was employed as a Senior Staff Engineer for Orbital Sciences Corporation in Arizona, where he worked on satellite communications, military equipment and aerospace technology.

As an older man, Gross got the most joy from visiting local schools and giving presentations. He took extra pleasure in inspiring the next generation of scientists, engineers and thinkers.

In April of the year 2000, Al Gross (who had garnered numerous awards throughout his career, far too many to write about here) was honoured to receive the Lemelson-MIT Lifetime Achievement Award. He passed away eight months later in December 2000.

Gross never actually retired and was still working at the age of 82, a restless paragon of forward thinking, innovation and tireless imagination.

SOURCE

http://web.mit.edu/invent/iow/gross.html

What Type Of Two Way Radio Should A Shopping Centre Use?

The truth is that shopping centres (or ‘malls’ if we’re being American about it), can seriously improve an area’s local economy. It is basic economics really, if the supply is less than the demand, then there is profit to be made. I expect a percentage, Deepak!

OK, I’ve thought a bit about this one and, I reckon your best bet would be an affordable, yet high performance unit like a Motorola DP3400 or similar. I suggested the DP3400 because it a) it won’t bankrupt the (hypothetical) project, b) it is very versatile and c) it is exceptionally easy to use (user training takes, on average, about 20 minutes).

A DP3400 offers use of 32 channels, functions as both analogue and digital and is available in UHF or VHF versions. In short, this radio is perfect for security, health and safety or even customer service.

I’ve recently found the ‘Case Studies’ sections on the Motorola website (you can probably tell by my other pieces this month), but the DP3400 has a case that’s exactly like yours. For what its worth, here’s what they said about it.

“Digital two-way radio was chosen to provide a secure, discreet communicationsystem with no risk of transmissions being compromised by eavesdroppers. The Centre’s local Motorola Authorised Dealer demonstrated how  MOTOTRBO digital radios could provide greater coverage and improved audio clarity than analogue and enable users to make both one-to-one and group calls. The increased battery power would extend battery life by up to 40%, enabling the radios to be used throughout the entire 11-hour trading day without recharging”.

That sounds pretty good to me. In any instance, you keep dreaming and don’t let anyone discourage you. Find out what it takes to be an…um, ‘shopping centre design person’ and just go for it! 

Private Pilots Shouldn’t Take Off Without a Backup Radio

Can’t get over how low-priced the two way radio is now, an incredible deal for a top-end product!

Those of you who follow my adventures know that I can fly to wherever there’s a communications emergency. Regular folks need a plane, and what do private pilots need? They need two-way radios, of course!

A recent story on TodaysWirelessWorld.com explained how many private pilots wouldn’t consider taking to the air without a backup radio. “Imagine what happens if an airplane’s primary radio fails in flight,” the story says. “You’re thousands of feet in the air at the controls of an expensive aircraft with no ability to monitor weather and emergency channels or communicate with control towers, ground crews, and other pilots. Getting down safely suddenly becomes more theoretical than a sure thing.”

The story goes on to review some key considerations for a pilot using a handheld aircraft radio as a backup:

Mind your power supply. “While rechargeable Lithium-Ion batteries usually have the longest battery life, you really want a rechargeable battery that will hold a charge for a very long time. Standard rechargeable batteries lose their charge quickly, but ‘low-discharge’ batteries can hold up to 70% of their charge for years on end.”

Get yourself trained. “On the ground, walk through all the steps for getting your backup radio up and running, including finding proper frequencies for nearby control towers. Also be sure to practice using your handheld in flight. Having the whole radio in your hand while working the plane’s controls is a bit more complicated than talking into a mic.”

Save your most-used frequencies. “Every radio manufacturer has its own way of saving most-used frequencies. Sometimes you’ll have to break out your user manual to figure out how to program and recall saved channels. Be sure to add the process for recalling saved channels to your drilling and training.”

That’s good advice for pilots and everyone else who needs to keep a two-radio handy in case of an emergency. A radio is a useful and versatile tool, but it’s up to us to make sure it’s ready to help us when we need it.

– See more at: http://blog.bearcom.com/2014/01/private-pilots-shouldnt-take-off-without-a-backup-radio-2/#sthash.3x2Oy4NG.dpuf

THE SHIFT TO DIGITAL, why NASCAR choose Motorola

NASCAR officials have enthusiastically embraced MOTOTRBO, and they applaud the benefits it has brought to the NASCAR experience. Smooth Management of Communications Traffic MOTOTRBO “does a super job for us,” according to Kerry Tharp, Director of Communications, NASCAR. “You have to communicate pre-race, during the race, and most importantly for us, post-race because when the race is over, that’s when our media operation kicks in for us full-bore. We bring in our top three drivers for interviews; we bring in our winning driver to the victory lane, and we also check in on the garage to make sure that post-race is going along as it should. We have to make sure we’re communicating quickly and concisely. Through MOTOTRBO, we’re able to do our jobs a whole lot better than we have in the past.”

A Clear Road for Communications Digital provided a measurable improvement over NASCAR’s old system, which sometimes had a slower response time. “MOTOTRBO has taken NASCAR to a whole new level.” Steve Lowery, Chief Scorer, NASCAR, explains, “With the old system, there was a lot of interference. Sometimes you couldn’t hear at all because of static. With MOTOTRBO, it’s much clearer.”

Consistency and Reliability

 You’d Expect from a Winner According to David Hoots, Managing Event Director, NASCAR, one of the most important benefits is “extended battery life because some of our days are extremely long. We have to be able to communicate consistently and reliably. MOTOTRBO has done a super job for us.” Hoots adds that MOTOTRBO is the first step toward an even more comprehensive communications system: “We took the opportunity to start with a very solid foundation and we will grow with the capabilities the radios offer. With a digital system, we’re going to reap the benefits for years to come.” “ With the old system, there was a lot of interference. Sometimes you couldn’t hear at all because of static. Now, with MOTOTRBO, it’s much clearer.”

Robust Enough for the Toughest Environments The NASCAR study, Hoots recalls, determined that the organization needed “one clear and uninterrupted communication system, and because we move from venue to venue, we’re faced with a big challenge.” The robust, durable and adaptable MOTOTRBO system was able to move from location to location – over 56 events every year, almost every month of the year – for quick deployment and certain performance. “Reliability,” says Hoots, “is of utmost importance. We cannot have a product that is going to fail. We must have the most robust system possible, so MOTOTRBO is the right system for us.” According to Michael Helton, President, NASCAR, “Fans have become interested in the entertainment aspect of listening in, so we still want an analogue system going out for fans who still use analog radios.” The ability of MOTOTRBO to support digital and analogue communications made it the perfect selection for

this blended environment that had to accommodate fans in the stands who want to scan for instant updates using older analog radios.

Twice the Capacity

MOTOTRBO is able to manage large numbers of radios by utilizing TDMA – time division multiple

access – which divides the channel into time slots for greater spectrum efficiency. TDMA enables each single repeater to do the work of two repeaters for enhanced call management with private, group, and system-wide calling capability. Digital Means Clarity MOTOTRBO supports audio quality with digital clarity and noise-canceling technology so that everyone is able to connect with one another and communicate more efficiently. MOTOTRBO radios contain a digital signal processor (DSP) that fine-tunes the audio. When a user connects an IMPRES™ intelligent audio accessory to a MOTOTRBO radio, the accessory provides the radio’s DSP with a unique set of audio parameters to shape the microphone and speaker frequency responses, ensuring the maximum clarity, volume, and intelligibility of each communication. “ Fans have become interested in the entertainment aspect of listening in, so we still want an analog system going out for fans who still use analog radios.”

Batteries Go Farther on a Single Charge MOTOTRBO is able to maintain consistent, reliable communications. All digital radios provide improved battery life, and because TDMA digital systems

utilize batteries more efficiently, users have received up to 18 hours of operation after quick-charging a standard nickel metal hydride battery. Talk-time is now extended and personnel spend less time returning to base to recharge their radios or pick up fresh batteries.

Robust Enough to Take on the Road

One key advantage of MOTOTRBO is that it’s designed to be packed up, moved to a new location and set up, only to be taken down days later and moved again. To withstand that kind of constant use, a radio has to be strong, and MOTOTRBO has proven to be very strong, robust, and durable.

Source – http://www.motorolasolutions.com/web/Business/Product%20Lines/MOTOTrbo/_Documents/Case_Studies/Static_Files/Events_Nascar_car_racing.pdf

New Analog-to-Digital Migration Guide Helps Users Take Advantage of the Latest Technologies

The basis of the post is to make you think about what in life is essential and what does getting the up-to-date two way radio really represent to us

All around us, the wireless world is going digital. But organizations have questions about this breakthrough technology. To provide them with answers, BearCom and Motorola Solutions teamed up to create our Analog-to-Digital Migration Guide: “Five Reasons to Migrate to Digital Two-Way Radios.”

“A ‘smart’ revolution is transforming two-way radios,” the guide begins. “Digital technology is opening the door to a host of useful web-based applications for two-way radios, even as it enhances capacity, coverage, audio quality, and battery life.”

Available as a free download from BearCom.com, the guide details how digital two-way radios offer additional functionality, greater efficiency, enhanced coverage, improved audio quality, and extended battery life compared to analog radios. It explores the capabilities and benefits of the latest radios, the differences between analog and digital technologies, and the process for making a smooth transition to digital.

“There are plenty of exciting new digital two-way radio products available,” reads the cover letter from BearCom President & CEO Jerry Denham. “This new Analog-to-Digital Migration Guide is the latest tool we’ve developed to assist organizations around the country as they harness the power of digital performance to improve their communications capabilities.”

The guide includes details on the MOTOTRBO line of digital two-way radios from Motorola Solutions and the new Motorola CP200d, which was made available through BearCom last summer. In developing the CP200d, Motorola Solutions was able to retain the simplicity and durability that have helped make the Motorola CP200 analog model popular across a wide range of industries.

The guide also answers frequently asked questions, such as:
Why should we go digital?
How are apps useful in two-way radios?
Will analog radios become extinct?
Are my analog two-way radio accessories compatible with digital models?
How can I get the best value when selecting digital two-way radios?

– See more at: http://blog.bearcom.com/2014/01/new-analog-to-digital-migration-guide-helps-users-take-advantage-of-the-latest-technologies/#sthash.hoMbIaZV.dpuf

I recently started watching NASCAR and I was wondering how the drivers communicate with the pit crew?

(Asked by Paul from Dublin, Ireland)

Y’know, I visited your fine city of Dublin many years ago and had a wonderful time. It is a truly magical place.

Anyway, on to your question….

NASCAR drivers use a unique radio system that is built in to their crash helmets. These are occasionally customized to suit the individual wearer. In addition to this, there is a push-to-talk button (exactly like the one found on a walkie-talkie), which is situated in the steering wheel. A wiring harness connects the various components together and a separate battery operates the whole thing. The signal is broadcast via a whip antenna that is attached to the roof of the car. In this fashion, NASCAR drivers are able to communicate with pit crews.

In addition to this, most cars are outfitted with a spare Motorola two-way radio that is within easy reach of the driver.

A firm out of Atlanta, Georgia named ‘Racing Radios’ provides the vast majority of the radios used in NASCAR races. Racing Radios have provided equipment to NASCAR races for 30 years or so; they are a trusted firm, creating all the standard NASCAR radio technology and also providing custom radios/peripherals for individual drivers.

According to Racing Radios spokesperson Tony Cornacchia, the majority of NASCAR drivers prefer to buy their own specialized equipment from the firm.

Because so many teams are racing and so many people are working on the race overall, it is not uncommon for NASCAR events to feature 100 FCC licensed radio broadcasts at any given time.Racing Radios is the company that programs the individual frequencies, not only for drivers and pit crews, but also for staff, officials and security personnel. RR do such a good job, that neither drivers nor pit crews suffer regularly from interference or dead spots. Now that’s something.

According to Terry Boyce of ‘HowStuffWorks’, “Many teams outfit their entire pit and support crews with custom-engineered, hand-built headphones and two-way radios ordered through Racing Radios. Multi-car teams may choose to connect even more people through their radio communications network. Active Noise Reduction (ANR) technology helps to cancel out distracting background noise. Exceptional communication is one of the reasons a 21st century NASCAR pit crew can change four tires and refuel a race car in around 13 seconds — and do it 10 or more times in a single race”.

I hope that answers your question, Paul. Have fun!

 

MOTOTRBO™ REMASTER YOUR WORKFORCE WITH THE RIGHT SOLUTION

The Mototrbo two way radio has numerous uses, but it works best at communicating two or more persons between one another, be it leisure or commerce, long distance communication is often vital in many different environments. This promotional article was initially a PDF at the motorola Site.

HELP TEAMS WORK BETTER AND FASTER, TOGETHER

Your people are on the factory floor, at the front desk, moving across campus or around the country. Hauling freight or handling emergency repairs, MOTOTRBO connects them instantly and efficiently, everywhere they go. Continue reading

Innovative or Simply Post-Modern? New Paradigms in the Study of “Radio”

Radio is the wireless transmission of signals through free space by electromagnetic radiation of a frequency significantly below that of visible light, in the radio frequency range, from about 30 kHz to 300 GHz. These waves are called radio waves. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space.
Information, such as sound, is carried by systematically changing some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.
Etymology
The etymology of “radio” or “radiotelegraphy” reveals that it was called “wireless telegraphy”, which was shortened to “wireless” in Britain. The prefix radio- in the sense of wireless transmission, was first recorded in the word radioconductor, a description provided by the French physicist Édouard Branly in 1897. It is based on the verb to radiate .
The word “radio” also appears in a 1907 article by Lee De Forest. It was adopted by the United States Navy in 1912, to distinguish radio from several other wireless communication technologies, such as the photophone. The term became common by the time of the first commercial broadcasts in the United States in the 1920s. The term was adopted by other languages in Europe and Asia. British Commonwealth countries continued to commonly use the term “wireless” until the mid-20th century, though the magazine of the BBC in the UK has been called Radio Times ever since it was first published in the early 1920s.
In recent years the more general term “wireless” has gained renewed popularity through the rapid growth of short-range computer networking, e.g., Wireless Local Area Network, Wi-Fi, and Bluetooth, as well as mobile telephony, e.g., GSM and UMTS. Today, the term “radio” specifies the actual type of transceiver device or chip, whereas “wireless” refers to the lack of physical connections; one talks about radio transceivers, but another talks about wireless devices and wireless sensor networks.
Processes
Radio systems used for communications will have the following elements. With more than 100 years of development, each process is implemented by a wide range of methods, specialized for different communications purposes.
Transmitter and modulation
Each system contains a transmitter. This consists of a source of electrical energy, producing alternating current of a desired frequency of oscillation. The transmitter contains a system to modulate some property of the energy produced to impress a signal on it. This modulation might be as simple as turning the energy on and off, or altering more subtle properties such as amplitude, frequency, phase, or combinations of these properties. The transmitter sends the modulated electrical energy to a tuned resonant antenna; this structure converts the rapidly changing alternating current into an electromagnetic wave that can move through free space.
Amplitude modulation of a carrier wave works by varying the strength of the transmitted signal in proportion to the information being sent. For example, changes in the signal strength can be used to reflect the sounds to be reproduced by a speaker, or to specify the light intensity of television pixels. It
was the method used for the first audio radio transmissions, and remains in use today. “AM” is often used to refer to the mediumwave broadcast band .
Frequency modulation varies the frequency of the carrier. The instantaneous frequency of the carrier is directly proportional to the instantaneous value of the input signal. Digital data can be sent by shifting the carrier’s frequency among a set of discrete values, a technique known as frequency-shift keying.
FM is commonly used at VHF radio frequencies for high-fidelity broadcasts of music and speech . Normal TV sound is also broadcast using FM.
Angle modulation alters the instantaneous phase of the carrier wave to transmit a signal. It is another term for Phase modulation.

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