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The History of Amateur Radio
The 2000s : a new millenium, wireless and code-less (XVII) At the dawn of a new millenium, it is like the world has sudently decided to change its way to communicate. Indeed, in a world in constant evolution, wired connexions looked restricting and cumbersome, for short old fashion... Wireless network solutions offer to all computer users in the widest meanings the freedom to be productive from any roaming location, and no more only from inside the computer room, their office or the ham shack. If a repeater can be connected to a computer network using a wired packet interface (e.g. Rigblaster interface), an amateur can also use a wireless connexion, using radio frequency technology to transfert information to the computer using the network protocol 802.11, better known as Wi-Fi. The wireless delivering speeds are ranging from 11 Mbps (802.11b, standard Wi-Fi) to 54 Mbps (802.11g and 802.11a) in single of parallel access ! The fastest access operating in 802.11a works on the frequency of 5 GHz. Designed in 1999, the certification began in March 2000 and is today supported by thousands products worldwide. Among devices supporting this technology name all Bluetooth peripherals that you will find to brands like IBM, U.S.Robotics, and other 3COM, cellular phones, laptops, Palm and Pocket PCs, cameras, and other Wi-Fi gadgets. PCMCIA cards or internal LAN adapters can be equipped of wireless capabilities. You can also install a gateway with router functions that will route both wireless and Ethernet clients simultaneously if you want for example sharing all together a remote connexion, an Internet access and share files and printers. Two standard networks are available : a Local Area (100-metre max radius, 802.11 standard) and a Personal Area (Targeted at 5-10 metres, Bluetooth standard) Networks. In addition, linking between LANs is also feasible, allowing building to building links of up to a few kilometres to be achieved. Thanks to the MAC address (serial number) of your card and the security associated to your login (SID, unique identifier) your more or less extended network can be protected, including with encryption, to prevent other people to access Internet or your peripherals through your connexion. In the field, up to 100 m away from a base Wi-Fi station, you can use your portable computer and browse Internet without to worry whether you inserted and configure or not your LAN card or your modem in your portable. You have only to plug your Wi-Fi Bluetooth card in your portable, install an USB driver suited to your operating system, and your remote system is ready to receive and transmit data (transfert file, access files, run applications, etc) with your Wi-Fi base linked (wired or even wireless) to your main computer. In fact applications now depend on your imagination ! An amateur radio can also use an handheld VHF transceiver and make contacts through the Internet with other hams working on HF or V/UHF. There is no magic but only one constraint : the Wi-Fi base station must be wired either to a packet interface linked to a HF transceiver or directly to a PC connected to the web and running a communication software like Echolink to name the most used utility reserved to amateurs. Space, where hams have gone before 40 years after the first OSCAR 1, AMSAT continues to launch satellites on orbit at a rate of approximatively one amateur satellite each 8 months, a rate much higher than any professional space agency, and continue to develop his interest in satellite communications and science. The amateur satellite AO-40 is a good example of this activity together high-tech and at educational purposes. AO-40 was launched on an Ariane 5 rocket from Kourou, French Guiana, on November 16, 2000. It was designed to serve at least ten years as an educational aid enabling students around the world to familiarize themselves with space techniques and communications. The designers also hoped the satellite would allow radio amateurs to use simple and inexpensive equipment to establish communications networks covering a large portion of the Earth for long periods of time thanks to its Molnya-like orbit (perigee as close as 810 to 1260 km above our planet and outward at apogee to 58,971 km).
AO-40 was built to carry two-way communications using transponders on numerous frequencies. It transmits telemetry data on radio beacons on several frequencies too in FSK and BPSK modes. All signals are digital, SSB or CW. FM is not permitted. For information, AO-40 transponders frequencies are next. Uplinks : 435 MHz with an EIRP circularly polarized of 21 dBWi, 1270 MHz at 23 dBWi, 2400 MHz at 27 dBWi and 5670 MHz at 34 dBWi. Downlinks are on 2.4 and 24 GHz. Where to start from ? If you are a novice, the most popular configuration to work with AO-40 is to transmit on 435 MHz and receive on 2.4 GHz. In transmission you need a 10-m HF transceiver, a transverter 10m-70cm as well as an 70 cm amplifier in front of the antenna. In receive you need a VHF or HF transceiver, a 2.4 GHz-2m downconverter and a 2.4 GHz preamplifier in front of the dish. As far as antennas are concerned, for transmit you need at least a 10-element crossed Yagi or a pair of crossed dipoles over a reflector plane. A rotator and a satellite tracking software are recommended. In receive you need a 60-cm parabolic dish (S/N 26 dB). The satellite signal strenght on the ground is of -167 dBWi at 2.4 GHz and -197 dBWi at 24 GHz. You will find an accurate band plan and the current satellite status on AMSAT website.
G5RV, Silent key The year 2000 is also marked by the decease of Louis Varney, G5RV, on June 28, 2000 at 89, who rejoined the large family of silent keys. Born on June 9, 1911 Louis held his first licence 2ARV in 1927. Following his initial aerial experiments in 1946 he shared with us the invention of the famous G5RV dipole antenna. Louis Varney's life is extensively detailed in this "Profile" written by Kenneth Hill, G3CSY, a reprint from "Mercury" the journal of the Royal Signals Amateur Radio Society. Work the world with EchoLink Developed in early 2002 by Jonathan Taylor, K1RFD, Echolink is a program using the Voice-over-Internet Protocol, VoIP for short, to establish long-distance communications (DX-like). The product has spread rapidly among the ham community and is today used by over 120,000 hams in 147 countries, with approximatively 2,200 connected users daily !
How can we explain such a success so rapidly ? We have first to understand how work this application. Instead of using ionospheric layers to establish long-distance communications, K1RFD suggested radio amateurs to use the VoIP protocol, thus Internet in combination with RF linking and specially with V/UHF FM transceivers to work ham stations. In this way he says, even hams limited to V/UHF bands and having difficulties to work DX stations can use Internet to have conversations with hams located all over the world, at distances exceeding by far the performance of their FM transceiver. Indeed, with time running it has appeared that this "web-assisted" tool has proven to be very useful and very performing. EchoLink uses two different systems : - Repeater linking where repeaters are linked each another through VoIP. Each amateur works with a fixed, portable or mobile VHF or UHF FM transceiver and emits to a FM repeater located a few dozen kilometers away. Of course if there is no reapeater at about 30 km around your QTH you cannot use this linking with echolink and you will have to work simplex. - Simplex linking. In this configuration there are two options. Either the amateur uses a V/UHF handheld or mobile transceiver or he is directly connected to the Internet. In the first case the ham work remotely and emits to his base station. This last uses a VOX interface linked to a computer that process signals digitally before to send them over the Internet. In the second case, the ham is directly connected to the Internet through his computer using a low speed modem (as low as 36K) or a DSL connexion. So in simplex linking the connexion can be done to other simplex nodes, to repeaters or even to hams directly connected to the Internet and using no ham equipment at all. Repeaters using simplex links with a radio receive a callsign with a -L suffix, repeaters running the software connected to a radio receive the -R suffix. Both run un SysOp mode. Who can use EchoLink ? All licensed hams - but only them - can use EchoLink, even if you are limited to V/UHF or owner of a Novice licence. Don't care if you do not have a good antenna or if you only own a low power VHF or UHF transceiver. You can work with Echolink without radio equipment, simply using the Internet if you like ! I suggest you to refer to my dedicated pages if you want more information about this tool. A new novice license in United Kingdom and Belgium On January 1, 2002 the United Kingdom introduced the Foundation license as a "radically different" entry-level approach to Amateur Radio. Among other new requirements, Foundation applications must demonstrate the ability to make an on-the-air contact. Foundation licensees sport M3-prefix call signs and have privileges on all bands from 136 kHz to 440 MHz - except 10 meters to avoid problems with CB - with a 10 W power limit on HF and 50 W on V/UHF. The RSGB had planned on an initial rush of 1000 candidates. Two years later they were 5,000 new licensees - with approximately a quarter of them under age 21. During that time, the main belgian amateur radio association UBA saw the number of its members decreasing from 6,000 in 1999 to a threshold of 2,500 licensees only early 2002. Seeing how fast has grown the English amateur community after the introduction of the Foundation license, UBA President John Devoldere, ON4UN, decided in september 2003 to request to the IBPT administration (equivalent to FCC) the right to replace the previous ON2 license by a Novice one similar to the English Foundation. Called Novice license or "licence de base", it was released on March 30, 2004. It is accessible to all people from 13 years old and gives access to HF (excepting 10m) and V/UHF bands up to 440 MHz with the same power limitation as in the U.K. This "QRP" license is the entry point to the HAREC license that the amateur will have to present to the IBPT if he wants to become a full privilege amateur radio. Very soon new European countries like Norway and Holland will introduce a similar license. Digital Radio Mondiale
Back to '90s. The DRM Consortium formed in 1998 when a small group of pioneering broadcasters and manufacturers joined forces to create a universal, digital system, DRM, for the AM broadcasting bands in HF, this wide band of frequencies including short waves, medium waves and long waves. Since then, DRM has expanded into an international consortium of more than 70 broadcasters, manufacturers, network operators, research institutions, broadcasting unions and regulatory bodies, with members represent more than 25 nations. In 2002 DRM received endorsement by the ITU for all three broadcasting bands (SW, MW and LW) between 150 kHz and 30 MHz. No other digital radio system has received such broad recommendation and for all three bands by ITU. DRM is not a registered trademark. This is a standard entered into force as of January 30, 2003. It will progressively replace classic AM broadcastings, and will become the "digital AM". Indeed, this new standard offers a higher listening quality : RFI, noises and fading practically disappear. As time running, new manufacturers are involved in this technology like WinRADIO for example that sold since 1996 receiver cards like the G-303i compatible with DRM thanks to an optional demodulator. Refer to my pages dealing with DRM and satellite reception for more information. Wake up fellows, this time the future is digital ! Walky-Talky Cell phone Beside the LPD and PMR transceivers free of license, there is another product taking advantage of walky-talky features, and more unattended. A few years ago, the company Thuraya released a satellite telephone not larger than a GSM (cell phones) including an intercom function between the receivers (acting like a walky-talky) completed with an autoscan and other sophisticated features. This Rolls-Royce of GSM equipped with a walky-talky function was expensive and used by very few people, mainly businessmen. On February 28, 2003, at the 3GSM World Congress in Cannes, Nokia, Ericsson and Siemens announced that they were working on a standard for adding walkie-talkie capabilities to GSM. On June 24, Nextel Communications and two other carriers expanded their services for a cell phone walkie-talkie feature called "Push To Talk" (PTT), to not confuse with the same feature offered by PMR devices.
Their idea began to interest economists and financials, and by August 2003 we saw the first competiton for the Push-to-talk technology between Nextel and Verizon, one of its competitor in joint-venture with Vodafone. Immediately Nextel decided to use Verizon for trademark infringement. As many others later, Verizon had to find another service name. In September 2003, US manufacturers released the first application allowing a GSM to act like a walky-talky. In November 2003, Nokia, the one "connecting people", provided the first PTT GSM, the Nokia 5140, displayed at left. It was available in Europe in septembre 2004. According to a poll made on August 2003 in the U.S.A by Zelos Group next to 1300 subscribers to mobile services (out of Nextel), 45 % of them declared wishing that their next GSM is equipped with the PTT functionality. The Push-to-talk comes thus in second position behind the picturing functionality. In February 2004, Sonim and Sony Ericsson collaborated to create an advanced model of GSM gathering the same functionality, the "instant talk" or "verbal SMS", a technology based on the "Push-to-talk over Cellular" (PoC) standard. At this occasion, Sony Ericsson released the model Z500. Some days later, Motorola, the 2d world manufacturer of GSM, introduced in the U.S.A. three new GSM with "walkie-talkie"-like features, including a model for the European market. Since that time, many manufacturers including Kyocera and Siemens jumped on this opportunity which is considered as the biggest upgrade to mobile phones since wireless service first became affordable a decade ago. Remember than GSMs work in bands of 900, 1800 and 1900 MHz but up to now they could only send one-shot messages (audio, text, images or video). This time some models allow you to use it as a walky-talky, the audio communication being transmitted life to a predefined users group. For example you tell to the group : "I offer champagne in an hour at home". An hour later be sure that all your friends will knock at your door... If a member of this group is missing, he could this time read the message when he will switch on his GSM. Unfortunately there will be no more champagne, Hi ! Of course you will be always credited for these communications. The alternate is to use the previous LPD or PMR transceivers free of use and free of charge, excepted the three small batteries. Their range is however more restricted. Last chapter
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