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The History of Amateur Radio

The Collins S-line of products taking advantage of the SSB.

The 1960s : Megahertz and small steps (XII)

After long discussions at international level, at the 11th General Conference on Weights and Measures (CGPM), the French "Bureau International des Poids et Mesures" (BIPM) decided to change the standard weights and measures system used till then (CGS, imperial units, U.S. customary units, etc) to the International System (IS), also known as "MKSA" by pupils.

The IS replaced for example the following fundamental units like centimeter, millibar, kgm/s2, farenheit or cycle with metre, pascal, newton, celsius and hertz, respectively. What a change ! This system received some additional corrections in 1971. If the IS "should be" in use in every country in the world, it is mandatory in many countries, and first of all in Europe. I remember well that in Belgium, when I was a kid, our professor of physics asked us specifically to use the new system. Even in American-English the words "meter" or "liter" are no more correct, the standard units being "metre" and "litre". Consequently in the next pages our dear "megacycles" will be replaced with "megahertz". Curiously, today we are more used to play with this second unit. A question of time and habit.

SSB becomes the standard operating mode

In 1960 QST magazine ran a survey of its readers to determine operating habits. They keep the idea of polls until now. At that time the division between AM and SSB operation fell at about 50-50, with the exception that 75% of voice operation on 20 meters was SSB. The old order of things was changing rapidly, all the more quickly that by 1960 transistors finally were being designed into most ham equipement, HF and V/UHF. Among the first SSB transceivers name the Heathkit SB-100 and the Collins S-line.

Within two years, if you still worked with an AM receiver, you had noticed that amateurs were gradually "invisible" on shortwaves. You heard well some unreadable noises on bands but nothing intelligible. In fact most amateurs moved either on LSB or USB mode.

Shortwave avids : CB and SWL

As the 1960 began, astute US observers noted that the new CB introduced in 1958 had effects on amateur radio. CB siphoned off many "would-be" hams who wondered why they 'd get a ham ticket when they could go on CB and work DX just like hams do ? The 11 meters was in pray to an intensive DX activity, and old ham gear, like the E.F.Johnson Viking Ranger, was ready to go on 11 meters with no modifications !

At left the E.F. Johnson Viking Ranger transmitter manufactured between 1954 and 1961. It works between 160 and 10m, including the 11-meter band, with 75 W in CW and 65 W in AM. At right a Trio 9R-4J which Kenwood (Trio) built also for Lafayette (as a kit
model KT-200 and the assembled version as the HE-10). The set's tuning dial is copied from the Hallicrafters S-38 receiver manufactured in 1946. It was priced at only $47.50, an affordable entry-level product for the listeners.

At the same time, while radio amateurs venerated their new SSB equipment, a new group of "would-be" hams appeared : shortwaves listeners, SWL. Avid youngsters but also much older fans of shortwaves built of their own small receivers, or bought inexpensive shortwaves sets like the Hallicrafter S-38 receiver. Unfortunately most of their two- to four-tube receivers picked up only CW and AM signals. Due to this limitation radio amateurs "disappeared" from the bands and listeners could no more copy the ham signals. But unfortunately for the amateur community, at few megahertz up, the AM signals of CBers were loud and clear ! As a result the growth pattern of amateur radio slowly deteriorated, peaking by 1966 as noticed QST. What could be the reason of this disinterest ?

In fact not only amateur radio experimented this disinterest but Boy Scouts for example reported also a drop in new members. Some analysts suspected that the social strain of the Vietnam war had something to do with it. Nobody was sure. Because on the other side, CB continued to gather more amateurs and sales of home-entertainement equipment (Hi-Fi sets and color TV) increased too. 

Birth of the electronic mail

The electronic mail (e-mail) that we all use at home of at work was invented in 1961. It was used at MIT as an internal mail program on the Compatible Time-Sharing System (CTSS) as well as by several other universities to share information between remote users accessing the mainframe through dial-up terminals. It became soon a network e-mail. This is of course ARPAnet that increased the popularity of e-mail, allowing users of network of different topologies and protocols to communicate together.

One of the first electronic mail (e-mail) exchanged in 1977 on ARPAnet using the standard format header (date, from, to, subject...) plus body, the content or the message to transmit. Soon after the CC, BCC and Received fields where added to the header.

Nowadays all e-mail systems are routed via Internet using the Simple Mail Transfer Protocol (SMTP). No one computer user could work without at last one e-mail connexion, installed either in his local system, at work, on a public server, or through a newsgroup or a forum.

Price of its success, unfortunately email addresses are very sensitive to spamming and viruses (email worms). To prevent this problem more and more servers like QRZ to name one, display the email address as graphics so that hackers cannot picked-up the info and send spam or viruses automatically to thusands of subscribers. There are also algoritms that check mailboxes and move automatically spams to a special folder.

This is in 1971 that Ray Tomlinson of ARPAnet sent the first e-mail giving instructions to the users on how to address mail to another user using the standard addressing format :, the first part before the "at" being the user login name or its alias, the second part, after the "at" or arobas, being the host server and domain name at which belong the mail server.

Packet radio uses also this concept when amateurs want to exchange messages via a TNC and a packet server (see two next pages). The address format is slightly different, like for example :

4U1ITU Radio club

In 1962, some members of the ITU decided to set up a radio club at the 5th floor of the first ITU building built one year earlier at Geneva, Switzerland. Some years later, an attempt to move the station at the 19th floor of the building built in 1970 failed, because not all members of ITU appreciated to see all these antennas on their roof. Even here there is no miracle !

4U1ITU began emission on June 10, 1962 at noon, Greenwich time. The picture displayed below at center shows the station as it was at the end '70s starring at foreground a Yaesu FT-101ZD HF transceiver with WARC bands.

4U1ITU QSL and hamshack by 1975 starring at foreground a Yaesu FT-101ZD. At right, the famous transceiver.

4U1ITU is an international radio club that survives, like many others, thanks to the subscriptions of his members and the devotion of some managers, most of them being members of the institute. 4U1ITU wanted to be active all bands and all modes. In practice several antennas have been set up at 25 m high on the roof. There are 3 elements Yagis to work on HF, and stacked Yagis steerable in elevation to work on VHF (6 m,  2 m). During the first years a beam was also set up for UHF. Operators work mainly in CW, SSB, RTTY and FSK31 modes.

The access to the shack is open to all licensed amateurs respecting the internal rule : to provide a valid amateur license, know how to use the equipment at disposal (you will be trained), confirming all QSO by QSL, and update the logbook. A station log must also be filled because the equipment has sometimes suffered of intense use.

Today, if you want to operate from 4U1ITU, contact simply the radio club manager by e-mail or searching the ITU phone number in the yellow pages. If you want to use the station during a contest, Luc, I1YRL, one of his QSL manager, could tell you that there is a waiting list exceeding 6 months. In all cases, have fun at 4U1ITU !

Space communications by microwaves

In watching the first space missions at TV and the equipment used by NASA to communicate with satellites and soon with the crews on orbit around Earth, it was the opportunity for some radio amateurs to experiment the first equipments dedicated to space communication.

In deep blue space wave and ground wave travelling from one antenna to another. In light blue paths of ionospheric waves in the upper atmosphere. Above the critical angle, waves escape in free space while waves emitted under a low incidence angle can reach DX stations.

Receive or transmit on space frequencies is a problem harder to solve that it could seem. We know (cf. NM7M's tutorial) that between 1-90 MHz the behavior of the ionosphere as mirror for the shortwaves is rather complex, with both reflexions and attenuations of the signal quite important. When the angle of fire is perpendicular to the ionospheric layers one can pass through the ionospheric layers at frequencies lower than the MUF, especially in time of low solar activity.

This principle was applied successfully to several ham satellites such AMSAT OSCAR and Radiosputnik launched from the years 1960s, some of them sending HF beacons or CW telemetry signals in mode A, downlink on 29 MHz (towards the Earth) and even on 20 or 21 MHz.

But working in this way is not without drawbacks and at daytime amateurs quickly discovered that the transponders of these satellites were affected by the F2-layer ionization during the periods of high solar activity. HF was thus not the panacea to work by satellite and they soon went up in frequencies, using in a first time VHF and UHF bands where commercial products were still easy to find and not too expensive. 

For sensitive high gain antennas, UHF carried still many interferences and various noises which are superimposed on signals. Today like at that time these RFI starts in the long waves (AM) with atmospheric noises (thunderstorms, etc), they extend to the VHF, sensitive to meteors ionization trails and auroras, to attenuate towards approximately 500 MHz. It was thus necessary to go very high in frequency to cut off from these problems. Eventually amateurs noticed that the world of microwaves, over the GHz, was also open to their activity and they could experiment a lot of new technologies in these bands.

First EME at 1296 MHz

During the first steps of the space conquest, amateurs began also to look at the Moon, wondering whether their Yagi could capture a microwave signal reflected by the Moon surface. On July 1960, the Rhododendron Swamp VHF Society in Massachusetts succeeded to work Moonbounce on 1296 MHz. 

This record was established by a team of amateurs from station W1BU, spearheaded by Sam Harris, W1FZJ, and W6AY, the Eimac Radio Club in California, always active, lead by O.H. "Hank" Brown, W6HB. Both stations used 1 kW surplus klystrons and dish antennas - not typical ham gear. This QSO gave an idea to another famous station.

In 1965, the largest radiotelescope in the World, Arecibo, in Puerto Rico (305 m in diameter) did the first Mounbounce contacts on 430 MHz at full power (some tens of thousands of kW !) with the call KP4I / KP4EOR. The gain was of 60 dB ! Many amateurs in North America did their first EME contact at this occasion, both in receiving and transmission. A similar test will be made again in the '80s.

Birth of SSTV

Back to 1957. This year the concept of Slow-Scan Television, SSTV, was defined by Copthorn Macdonald, WA2BCW, now VY2CM, who developed also the first video camera, the Westinghouse 7290 vidicon in 1958. In 1960, FCC grants a Special Temporary Authorization (STA) to send SSTV. It was limited to those who Macdonald had given 7290 vidicons. 

While commercial television required a bandwidth of a few megahertz, in MF/HF bands signals require a bandwidth of a few kilohertz only. It was thus impossible to squeeze the thirty 525-line images per second in such narrow bandwidth. Macdonald created thus a new standard, SSTV. The early SSTV transmission used a bandwidth 1500 to 2300 Hz wide, a range wide enough to represent a grayscale from white to black. The first screens were radar surplus displays using very-long-persistence phosphor (P7). At the end of the 8-minute transmission, the image became to fade but was still visible. To send color images, the sender had to transmit the same picture three times, each time with a red, green or blue filter (RGB) in front of the vidicon. The receiving operator took three long-exposure photographs of the screen, placing RGB filters in front of the camera's lens. This was known as frame-sequential color SSTV.

At left, Copthorn Macdonald, WA2BCW, now VY2CM, in his hamshack in 1973. At center, the drawing of a vidicon tube. It can be as small an ordinary vacuum tube. At right, an SSTV image received by PE1MNF on February 10, 1999 from MIR. Image recorded with CromaPIX software in Robot 36 mode FM on 145.985 MHz.

In the fall of 1968, SSTV was authorized by the FCC. This new digital mode permits amateur to transmit and receive static B/W or color pictures. SSTV uses a bandwidth 3 kHz wide on dedicated frequencies and quite specialized equipment (camera, modem, software, etc). Standard vidicons were developed the same year by WB8DQT and K7YZZ.

In 1970, W7FEN invented the Double Sideband SSTV, providing simultaneously voice on lower sideband and SSTV on upper sideband. Vidicon images suffer distortion (pincushion and barrel) as electrons travel along the vidicon tube.  The frame-sequential method had also problems among them the fact that the color image didn't appear until the final frame was received. But worse, any noise or RFI could ruin the image registration and spoil the picture.

In the mid '70s, solid-state technology allowed to save the three RGB images in memory and to display them simultaneously on a color TV. The next step was the line-sequential method. Each line was scanned three times, one time for each color. Pictures could be seen in full color as they were received and overlay problems of the frames were reduced. Among these modes of transmission name Martin, Scottie and Wraase SC-1, three SSTV RGB modes accepting up to 256 lines.

At last rather than sending color images with RGB components, Robot Research addeds luminance and chrominance signals to the 1200C modes. This encoding made more efficient use of the transmission time. A 120-line color image could be send in 12 seconds instead of the usual 24 seconds. The 1200C introduced also the vertical synch signal (FSK) to encode the transmission mode.

Today, SSTV takes advantage of Coupled-Charged Device (CCD) camera and signals are handled through the sound card of computers and windows applications. This is really not a complex configuration to set up, excepted that settings of the SSTV software (MMSSTV, ChromaPIX, etc) need some habits if you want an image free of slant and well synchronized.

First OSCAR Satellite

This is in 1961 that a group of american amateurs built and launched the very first Amateur Radio satellite OSCAR 1, standing for Orbiting Satellite Carrying Amateur Radio, a term that is still used today to identify most Amateur Radio satellites. OSCAR 1 was launched on December 12, 1961, barely four years after the launch of Russia's first Sputnik. OSCAR 1 measured about 30 x 25 x 12 cm for a weight of  4.5 kg. 

OSCAR 1 used a 140 mW transmitter that discharged its non-rechargeable batteries after three weeks of operation only. 570 amateurs in 28 countries received however its sympathetic 'HI-HI' signal in Morse code on VHF at 144.983 MHz until January 1, 1962. The sample provided in the link was recorded on December 14, 1961 by Roy Welsh, W0SL, at half-speed so that the signal is well readable. Here is the same signal recorded at normal speed but harder to read. The speed of the HI-HI message was controlled by a temperature sensor inside the spacecraft. OSCAR 1 re-entered the atmosphere on January 31, 1962 after 312 revolutions. It was followed six months later by OSCAR 2, using a design almost similar. Since that time, in average amateurs have launched one satellite each year on orbit.

We have had to wait until 1969 to organize this activity inside an amateur association, the Radio Amateur Satellite Corporation, AMSAT, an educational organization chartered in the District of Columbia, USA. Its aim is to foster Amateur Radio's participation in space research and communication. 

But this is really in the years '80s that the space what really conquered by amateurs, supported by the Russian ham community (Phase-3A, UO, RS satellites, etc).

1969 : Apollo XI landed on the Moon

After the slap of the Sputnik, in these years of Cold war, the U.S.A. had to show to the world how power could be their technology and their volunty to protect the freedom. If the unavowed goal of the space conquest was first to build intercontinental missiles to respond to any attack from Soviets and their Warsaw Pact allies, Kennedy Administration could never avow their intention in public. They thus had to find a stratagem so that citizens, thus Congressmen, accept that a substential fraction of the national budget be allocated to the building of huge ballistic vectors like Minuteman's and other rockets. 

After have consulted specialists like Dr. Wernher von Braun, the President John F. Kennedy declared in front of the American Congress on this May 25, 1961: "Before the end of this decade we will land a man on the Moon, and we will return him safely to the Earth". Such was the insane bet of America after the successful flight of Yuri Gagarin five weeks earlier... It will be however necessary to wait until February 20, 1962 to see John Glenn orbiting three times around the Earth. The foolish bet was well started.

To listen to : John Glenn's audio files

At left President John Fitzgerald Kennedy declaring at the Congress on May 25, 1961 his decision to send a Man to the Moon before the end of the decade. At right on July 11, 1969 Neil Armstrong successfully landed the Eagle on to the Moon. He will say these words became famous : "it's one small step for man, one giant leap for Mankind"... This time Russia gave up the Moon to the U.S.A. and focus on manned space stations. Clic on the right image to launch a film showing the LEM landing on July 21, 1969 (1.1 MB .mov) and listen the famous sentence : "Tranquility Base here. The Eagle has landed". Clic here for a long version (23 MB .avi).

New licenses

While hundreds of millions eyes looked incredulous at their TV screen the progress of Apollo program, in the U.S.A, FCC changed one more time the ham privileges. Back in 1952, they gave to all HF classes identical privileges. Many hams who had advanced skills wanted the incentive licensing system back and informed ARRL of their whish on October 1963. It was followed with a large debate during which the number of licensed hams decreased gradually in the USA as we noticed previously. At the end FCC restores incentive licensing on August 24, 1967. Exclusive segments on 80, 40, 20,15 and 6-meter bands were set aside for Amateur Extra and Advanced class licensees and withdrawn from use by General hams. Of course this decision displeased to all General who lost a part of their bands. FCC's decision partly subsisted until now and continue to feed forums and columns in magazines. In most other countries such "exclusivities" do not exist, excepted for Novices and other Foundation licensees like there are in the U.K.

In Belgium, this is in the '60s that the Morse code examination was removed to access bands over 30 MHz. All owner of an "ON1" license could work on VHF and upper frequencies, in any mode. Many belgian amateurs forced to work on VHF took advantage of this opportunity to develop their skills in the new-born space communications. The know-how of these "technicians la belge" was perpetuated until today.

Next chapter

The 1970s : The FM repeaters

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