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Doug21201
Glad to see so many favorable comments on the article. I recently read that ...
Ham radio in the 21st century
Doug Grant
11/7/2011 7:42 AM EST
Editor's Note: Doug Grant is a regular contributor to the RF&Microwave Designline with his Ham's Eye View blogs. Here is a piece that he wrote for our sister publication, EDN. I have excerpted the beginning for you, and included a link and some key points for the remainder of the article before the link at the bottom.
Many of today’s experienced engineers got their start in electronics through amateur, or “ham,” radio. (Many theories exist over the origin of the term “ham radio,” but there is no consensus.) Over the years, however, the demands of these engineers’ work, families, and communities took precedence, and many hams lost interest and let their licenses lapse. Meanwhile, with the rise of personal communications and Internet connectivity in homes, many young engineers never needed ham radio as a way to explore electronics. They’ve missed the opportunity that this fascinating hobby presents.
The first wireless communicators were by definition all amateurs. Guglielmo Marconi himself, generally regarded as the inventor of radio, once famously remarked that he considered himself an amateur. In the early days of radio, commercial, government, and amateur stations shared the same spectrum, sending broadband spark-generated transmissions modulated by on/off keying using Morse code to convey messages. This practice resulted in a horrendous amount of interference among services until the government stepped in and assigned various services to specific bands.
Government and commercial stations were assigned the supposedly more useful, less-than-1500-kHz, long- and medium-wave spectrum, and the amateurs were banished to the less-than-200m wavelengths with frequencies higher than 1500 kHz. The experts of the day regarded these bands as worthless for long-distance communications.
The amateurs soon discovered that long-distance communications were actually easier at these frequencies. New allocations were then created to give government and commercial stations some of the “good” spectrum. However, a handful of slices of the spectrum were reserved for the amateurs. In the late 1960s, amateurs laid claim to all of the apparently useless frequencies higher than 30 GHz. Since then, as technology has marched on, other services have discovered that these frequencies are useful; amateurs currently enjoy exclusive rights to the frequencies greater than 300 GHz.
In the United States, Part 97 of Title 47 of the Code of Federal Regulations controls the amateur-radio service (Reference 1). It expresses the fundamental purpose of the amateur-radio service in the following principles: recognition and enhancement of the value of the amateur service to the public as a voluntary, noncommercial communication service, particularly with respect to providing emergency communications; continuation and extension of the amateur’s proven ability to contribute to the advancement of the radio art; encouragement and improvement of the amateur service through rules that provide for advancing skills in both the communications and the technical phases of the art; expansion of the reservoir within the amateur-radio service of trained operators, technicians, and electronics experts; and continuation and extension of the amateur’s unique ability to enhance international goodwill.
Licensing
Part 97 requires that amateur stations obtain licenses before they can transmit. The process for getting a ham-radio license has evolved over the years. Long ago, an applicant had to pass a rigorous technical exam that included drawing schematics from memory. The exams have changed considerably. All of the questions are now multiple-choice and cover technical, operating, and regulatory topics, and all of the questions and answers—both right and wrong—are available in the public domain. Furthermore, the governments of many countries—notably, the United States—have effectively outsourced the job of testing.
In the United States, volunteer examiners now administer the examinations. Volunteer-examiner coordinators arrange for testing sessions at convenient places and times (Figure 1). Upon successful completion of an exam by an applicant, the coordinators forward the required data to the Federal Communications Commission, which then issues licenses, with call signs—to identify each licensee and his or her location of license using a prefix and a suffix. In the United States, three classes of license now exist, each conveying a set of privileges, including permitted bands, modes, and power levels. Passing a more advanced exam entitles the licensee to more privileges.
The US amateur-licensing process no longer requires knowledge of Morse code for any class of license. This requirement has historically been a major impediment for many technically skilled individuals who were interested in ham radio but who could not or would not conquer Morse code. Ironically, the portions of the bands reserved for CW (continuous-wave) operation are busier than ever, as new licensees discover that narrow-band modes are more effective for weak-signal work than are wider-bandwidth modes, such as SSB (single-sideband) voice.
Many amateurs make contacts using voice modes, primarily SSB mode on HF and FM on VHF and UHF. The signal- processing capabilities of a soundcard-equipped PC that connects to an HF SSB or a VHF FM transceiver have driven the emergence of new modes. Even a modestly equipped PC has sufficient speed to generate and decode the FSK signals for conventional radio teletype. Experimenters have created modulation schemes and accompanying protocols, complete with forward-error correction, which enable direct keyboard-to-keyboard contacts even with low power and small antennas. The variety of FSK and PSK signals being used create unusual buzzing and chirping sounds when traveling to a speaker, and computers easily demodulate them and turn them into legible text. Some ingenious hams even use the PC’s signal-processing capabilities to emulate the signals that World War II-vintage mechanical text-to-radio systems, such as Hellschreiber, generated.
Some hams also engage in transmission of full-motion video signals—usually on VHF or UHF bands, on which sufficient bandwidth is available. Others transmit still pictures on HF, using voice-bandwidth signals and a PC. Data networks have also evolved using various systems, including TCP/IP.
Follow this link to read the complete article on EDN, additional topics include 21st century equipment and the state of the art.
References
[1] Part 97, Title 47, Federal Communications Commission, Sept 7, 2006, pg 587.
About the Author
Doug Grant, K1DG, received his first ham-radio license from the FCC in 1967 and his bachelor’s degree in electrical engineering from Lowell Technological Institute (now the University of Massachusetts—Lowell). He has more than 30 years’ experience in the semiconductor industry, mostly at Analog Devices, where he worked in engineering; marketing; and product-line management for analog, mixed-signal, RF, and wireless products. He has logged close to 500,000 contacts with other radio hams in every country in the world. Grant is now an independent consultant specializing in semiconductor and wireless technologies.
Many of today’s experienced engineers got their start in electronics through amateur, or “ham,” radio. (Many theories exist over the origin of the term “ham radio,” but there is no consensus.) Over the years, however, the demands of these engineers’ work, families, and communities took precedence, and many hams lost interest and let their licenses lapse. Meanwhile, with the rise of personal communications and Internet connectivity in homes, many young engineers never needed ham radio as a way to explore electronics. They’ve missed the opportunity that this fascinating hobby presents.
The first wireless communicators were by definition all amateurs. Guglielmo Marconi himself, generally regarded as the inventor of radio, once famously remarked that he considered himself an amateur. In the early days of radio, commercial, government, and amateur stations shared the same spectrum, sending broadband spark-generated transmissions modulated by on/off keying using Morse code to convey messages. This practice resulted in a horrendous amount of interference among services until the government stepped in and assigned various services to specific bands.
Government and commercial stations were assigned the supposedly more useful, less-than-1500-kHz, long- and medium-wave spectrum, and the amateurs were banished to the less-than-200m wavelengths with frequencies higher than 1500 kHz. The experts of the day regarded these bands as worthless for long-distance communications.
The amateurs soon discovered that long-distance communications were actually easier at these frequencies. New allocations were then created to give government and commercial stations some of the “good” spectrum. However, a handful of slices of the spectrum were reserved for the amateurs. In the late 1960s, amateurs laid claim to all of the apparently useless frequencies higher than 30 GHz. Since then, as technology has marched on, other services have discovered that these frequencies are useful; amateurs currently enjoy exclusive rights to the frequencies greater than 300 GHz.
In the United States, Part 97 of Title 47 of the Code of Federal Regulations controls the amateur-radio service (Reference 1). It expresses the fundamental purpose of the amateur-radio service in the following principles: recognition and enhancement of the value of the amateur service to the public as a voluntary, noncommercial communication service, particularly with respect to providing emergency communications; continuation and extension of the amateur’s proven ability to contribute to the advancement of the radio art; encouragement and improvement of the amateur service through rules that provide for advancing skills in both the communications and the technical phases of the art; expansion of the reservoir within the amateur-radio service of trained operators, technicians, and electronics experts; and continuation and extension of the amateur’s unique ability to enhance international goodwill.
Licensing
Part 97 requires that amateur stations obtain licenses before they can transmit. The process for getting a ham-radio license has evolved over the years. Long ago, an applicant had to pass a rigorous technical exam that included drawing schematics from memory. The exams have changed considerably. All of the questions are now multiple-choice and cover technical, operating, and regulatory topics, and all of the questions and answers—both right and wrong—are available in the public domain. Furthermore, the governments of many countries—notably, the United States—have effectively outsourced the job of testing.
In the United States, volunteer examiners now administer the examinations. Volunteer-examiner coordinators arrange for testing sessions at convenient places and times (Figure 1). Upon successful completion of an exam by an applicant, the coordinators forward the required data to the Federal Communications Commission, which then issues licenses, with call signs—to identify each licensee and his or her location of license using a prefix and a suffix. In the United States, three classes of license now exist, each conveying a set of privileges, including permitted bands, modes, and power levels. Passing a more advanced exam entitles the licensee to more privileges.
The US amateur-licensing process no longer requires knowledge of Morse code for any class of license. This requirement has historically been a major impediment for many technically skilled individuals who were interested in ham radio but who could not or would not conquer Morse code. Ironically, the portions of the bands reserved for CW (continuous-wave) operation are busier than ever, as new licensees discover that narrow-band modes are more effective for weak-signal work than are wider-bandwidth modes, such as SSB (single-sideband) voice.
Many amateurs make contacts using voice modes, primarily SSB mode on HF and FM on VHF and UHF. The signal- processing capabilities of a soundcard-equipped PC that connects to an HF SSB or a VHF FM transceiver have driven the emergence of new modes. Even a modestly equipped PC has sufficient speed to generate and decode the FSK signals for conventional radio teletype. Experimenters have created modulation schemes and accompanying protocols, complete with forward-error correction, which enable direct keyboard-to-keyboard contacts even with low power and small antennas. The variety of FSK and PSK signals being used create unusual buzzing and chirping sounds when traveling to a speaker, and computers easily demodulate them and turn them into legible text. Some ingenious hams even use the PC’s signal-processing capabilities to emulate the signals that World War II-vintage mechanical text-to-radio systems, such as Hellschreiber, generated.
Some hams also engage in transmission of full-motion video signals—usually on VHF or UHF bands, on which sufficient bandwidth is available. Others transmit still pictures on HF, using voice-bandwidth signals and a PC. Data networks have also evolved using various systems, including TCP/IP.
Follow this link to read the complete article on EDN, additional topics include 21st century equipment and the state of the art.
References
[1] Part 97, Title 47, Federal Communications Commission, Sept 7, 2006, pg 587.
About the Author
Doug Grant, K1DG, received his first ham-radio license from the FCC in 1967 and his bachelor’s degree in electrical engineering from Lowell Technological Institute (now the University of Massachusetts—Lowell). He has more than 30 years’ experience in the semiconductor industry, mostly at Analog Devices, where he worked in engineering; marketing; and product-line management for analog, mixed-signal, RF, and wireless products. He has logged close to 500,000 contacts with other radio hams in every country in the world. Grant is now an independent consultant specializing in semiconductor and wireless technologies.
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colinholland
11/7/2011 9:24 AM EST
The UK's Radio Society of Great Britain is currently carrying out extensive discussions on its future. http://www.rsgb.org/ The aim is to create the sort of RSGB that is not only relevant to current members, but also attractive to new ones.
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kdboyce
11/7/2011 12:26 PM EST
I hope the RSGB is successful in its efforts. As someone coming back to the hobby, I find the equipment, and operating options to be much greater than when I was first licensed in 1956.
The wide range repeater options and capabilities on 144MHz and 440MHz are mind boggling. So I am having to learn yet again.
Ken - W8VMM
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antiquus
11/7/2011 3:14 PM EST
Within the last year or so, DHS has quietly forced amateur repeaters off of commercial television towers, on the premise that commercial TV is important for "public emergency" communication, and is therefore a strategic asset with controlled access to the facilities. The result is, of course, that hams (who are the real tactical emergency communications asset) have been forced to relocated their repeaters to less desirable and often less effective locations. Yeah, I feel safer already.
I hope someone soon compares the federal attitude towards hams on a "then and now" basis.
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Navelpluis
11/9/2011 4:36 AM EST
Everyone involved in some kind of HAM radio knows the enormous spectrum of all technologies involved in our spare time hours. From antenna to RF amplifier design, from mixer input stages to GHz dishes. And even more: Restoring WW-II equipment and even collect and restore clandestine transceivers and crypto equipment as on www.cryptomuseum.com
Have fun !!
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Edward Thermals
11/9/2011 8:47 AM EST
Most of us "RF" types grew up fascinated with 2-way radio, and electronic circuits. This is our passion and what we are. Today I see younger technical types only interested in showing others how to surf the internet. Even when I meet some of today’s younger hams, they are mostly going to buy something “off the shelf”, rather than build. We find tomorrow’s experienced two-way types will mainly come from the military. Ed.
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JohnnnS
11/9/2011 8:56 AM EST
Look, we all know the ham radio has devolved as a way to attract young people into electronic technology. That path has been killed. It is no more. We should stop lamenting this and just accept that ham radio is a niche hobby that will always be popular with a few souls who enjoy all the varied aspects of the hobby. Besides, I doubt we need a whole bunch of new RF designers banging on the doors of companies not looking to hire.
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Earl54
11/9/2011 10:36 AM EST
Well, let's see. About the comment of RF designers. The article mentions software defined radio, as well as numerous digital modes. Sounds like a lot of digital and software design, not necessarily all RF. In fact, the hobby can encompass just about any electronic or computer related engineering. Even mechanical, if you build your own enclosures.
As for the niche, yes, it is a niche hobby, always has been. But that niche serves a purpose, and that is emergency communication. You may pooh pooh that idea with cell phones and the internet, but my fiber to the curb connection went down went the power went off in the April tornados. The cell phone also became virtually unusable, as the cells remaining after the tornados went through were quickly overloaded. Guess what "hobby" was helping with the emergency communication?
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Jim Stockton
11/9/2011 9:15 AM EST
I grew up converting WW2 Command Radios for amateur use, then building transmitters out of TV sweep tubes. It was a great learning experience. Most Hams today are appliance operators or CBers with better bandwidth and power. The experimenters are few and far between. The thought of 300GHz and above is daunting as Si probably doesn't have enough electron mobility. Will be interesting to see what could come from the experimenters in the future.
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Texassignaltech
11/9/2011 10:08 AM EST
While it is true that fewer of the younger generation is joining the ranks of the amateur radio community, that path has certainly not been killed. Those in positions of leadership and regulation have had to implement changes (good and bad) in order to keep our great hobby alive. To us it is much more than a hobby. Many discoveries, inventions and patents were founded by experimentation thru ham radio, including the proven viability of the VHF/UHF spectrum. I am confident that amateur radio will continue to spark interest in young and old alike, as long as we show them the way.
David Pollard, N5IT, USN Retired
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masher
11/9/2011 11:43 AM EST
The appliance operator comments and the SDR comments basically theorizing that RF skills will be left in the dust is not entirely true, and it doesn't have to, engineering and ham radio are about learning and modifying your skills to fit new technologies.
Since I'm an RF power amp designer I doubt that SDR radios will ever make my power amp designs go by the wayside but certainly the dedicated receiver designers will need to upgrade their skills.
It all depends on what you want to do with ham radio and like the author says finding the time to do your projects is a big show stopper at times.
I just put together a 900 MHz to 10 meter FM repeater/remote base and since I wanted something more than a vertical antenna I went overboard and built a small yagi antenna.
Now I need to find a way to turn the yagi antenna via the 900 Mhz side, here comes the programming part of this boondoggle of mine.
I am now refreshing my C skills to make a rotator controller that works via DTMF commands.
In one week I have worked every continent on HF FM, built a repeater with a HF remote base, a controller to send the remote ID an antenna to reach further, re-built 2 power supplies and am now at the C programming end of things to steer my antenna.
I'll probably elect the help of one of our new codeless tech hams at work for the guidance on the C part of things.
In the process this young engineer will learn a lot of RF while I'll get some code refresher skills and as I'm sure you all know, these projects are constantly evolving so this is just the biginning.
Lets see maybe the next project will be an FPGA remote base, we have another codeless tech ham at work who is an FPGA guru and he needs to get back into ham radio.
Catch you on 10 FM some day if I can get the antenna rotator controller working.
Mike
WB8VLC/7
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w1dry
11/9/2011 8:48 PM EST
Heh what do you know . . someone finally wrote an article about Ham Radio.
And it ends up being Doug Grant . . . Nice article
de Michael Wyman
W1DRY/7 (formerly WB1CWD)
University of Lowell
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Robotics Developer
11/9/2011 8:13 PM EST
I always wanted to get a ham lic but could not get my head around the Morse code requirement (even as a kid I just couldn't see to learn it). Maybe now I will re-look at getting licensed.
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radiomanwy9a
11/10/2011 1:23 AM EST
Another excellent article Doug. As promoting ham radio articles go, that's one of the best I've read in recent years. Keep up the good work.
73 de Ed - WY9A
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Batman
11/10/2011 2:01 PM EST
Well done Doug, hope to meet you on the air someday.
73, N1XOI
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RobTheMagnificent
11/10/2011 7:53 PM EST
RF design is only one aspect of ham radio. Ham radio is electrical & electronics engineering with a living face, a lifestyle of perpetually interesting & useful applications, and a fraternity of some of the most talented & most qualified & friendliest people in all of the related disciplines. Ham radio embraces every aspect of wireless, not just RF – antenna to mic & speaker, keyboard & display, power plug & ground cable, and beyond. It includes systems engineering & integration, human factors & ergonomics, usage & practical application, and operator training & skill – all the technical & human disciplines connected to wireless technologies one way or another, regardless of the age of the technology or the person. Yes, it’s an avocation for old guys who can't leave vacuum tubes alone (real radios glow in the dark!), and folks who have an abiding love for a strange old language that burns thru noise with the simplest gear, Morse code. It's also a place where the future is tangible – kids talk to astronauts & learn what radio can do firsthand, college students loft balloon experiments & satellites, commuters talk to friends on the local repeater & to other friends on other repeaters multiple time-zones away – without a cell phone; it’s talking over multiple time-zones with no network in between; it’s participating at the EOC to work thru flood/ fire/ tornado/ earthquake impacts. Ham radio is about friends, new & old, and doing what's fun, and doing what one loves to do, at home in some spare time as well professionally. Yes, it's a hobby, so it takes a back seat when life's obligations intrude; it shares one's life along with other interests. It's *not* a sour lament about how no one's interested in hiring RF designers, because RF design touches a much wider domain than just ginning up a new wireless gizmo for sale. And it's far from dead. ... Doug, thanks for a great article, and a chance to poke the world a little about the hobby! Best regards, Rob / W3RUM
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Doug21201
11/11/2011 1:38 PM EST
Glad to see so many favorable comments on the article. I recently read that there are now 700,000 hams in the U.S. - an all-time high. I did not even get to discuss the operating side of ham radio in the article. After all, ham radio was the original "social network". Maybe I'll cover some of that in my blog. 73, Doug K1DG
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masher
11/16/2011 12:51 PM EST
Nice comments from evryone, glad to see good positive rssponses.
Hello Mike Wyman, WB1DRY/7 DE WB8VLC/7 up in oregon now, are you still in AZ ?
Nice to see your still around.
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