The Amateur Radio Service benefits society in a variety of significant ways. Between providing critical communications in times of emergency when traditional methods often fail, to enhancing international goodwill and creating new and innovative applications of emerging technologies, Amateur Radio Operators have demonstrated a long-term ability for achieving real-world results through practical and affordable means. This is an accomplishment that even well educated engineers cannot always achieve.
For millions of individuals (myself included), Amateur Radio provides an invaluable working environment upon which engineering theory can be put to practical and personal use. The experience, intuition, and ingenuity gained in this venue simply cannot be compared with learning experienced on the web, expressed through a textbook, or conveyed in a classroom. Being practical in nature, such expertise is extremely valuable in the professional world, and has become a scarce commodity. It comes as no surprise that some of the world's best engineers come from the ranks of Amateur Radio Operators.
Amateur Radio is a practical extension of my interest in electronics. As such, much of the radio equipment I use is homebuilt, and sometimes self-engineered. As an amateur radio operator, my interests and activities gravitate toward intermediate and advanced communication methods and techniques. It is these areas that generally hold my interest and present more of a challenge to me than others.
While studying for my licensing exam in 1983, I participated in several Morse Code Proficiency Qualifying Runs sponsored by the American Radio Relay League (ARRL).
I earned both the basic certificate for 10 WPM copy, and the 15 WPM endorsement sticker prior to taking the 13 WPM FCC code test (Element 1B) required for my Advanced Class License.
My first transmitter cost nothing to build. It was constructed in the housing of an old Knight Space Spanner shortwave receiver, and used components from this and other outdated electronic equipment that was on hand. A 375 volt D.C. power supply powered the transmitter, and was housed in a separate enclosure.
The transmitter consisted of a 6AQ5 crystal-controlled Colpitts oscillator feeding a 6BQ5 power amplifier. With about 30-watts input on the plate of the 6BQ5, and a quarter-wave end-fed wire antenna just 15 feet above the ground, this transmitter provided many solid CW contacts across the entire eastern half of North America. It saw its heaviest use between August 1983 and February 1984, and operated on a frequency of 7.137 MHz.
A vintage Hammarlund HQ-140-X receiver was used in conjunction with my homebuilt transmitter. In the mid-1980s, the Hammarlund's electronics were removed, and the receiver was completely re-designed around modern solid-state components. In general, JFETs replaced the 6C4 and 12AU7, and dual-gate MOSFETs replaced the 6BA6s. An LM1496 integrated circuit replaced the 6BE6 mixer, and an LM380 replaced the 6V6 audio output tube. An LM7812 became the functional equivalent of the OC3.
Although the basic functions of the receiver remained the same, several performance enhancements were made to the receiver during its conversion from a "hollow-state" to a "solid-state" design. In particular, the AGC now functions when the BFO is in use. In addition, a ceramic I.F. filter, an FM detector, and noise-activated squelch were added to the basic receiver design. (The squelch works on A.M., too.) The receiver now operates from an internal regulated 12 volt DC power supply. It requires no warm-up time, and exhibits far less frequency drift than the original design.
A second transmitter was built in September 1983. This transmitter was VFO controlled, and operated on the 75-meter band. It consisted of a Heathkit VF-1 VFO feeding a single 6BQ5 power amplifier. The 250 volts required by the VF-1 was "stolen" from the Hammarlund receiver. The output power from this arrangement was about 15 watts. Up to 30 watts was possible using a pair of 6BQ5s in parallel. Plate modulation of the 6BQ5s allowed voice contacts on A.M.
Around December 1983, a Swan 500 CX transceiver was pressed into duty on SSB and CW using a multi-band dipole antenna 25 feet off the ground. With over 300 watts of output power, this rig packs quite a punch along with exceptional audio quality.
In February 1984, a 10-meter FM transceiver was built around a surplus Hy-Gain (Cybernet) C.B. radio chassis. Poly Paks (remember them?) sold the Hy-Gain circuit boards for $12.95. A second board could be purchased for just one penny. Once converted to 10-meter FM, this transceiver provided scores of contacts, including many that took place through the W2IBJ repeater on the island of St. Thomas in the U.S. Virgin Islands.
In August 1985, astronaut Dr. Tony England, W0ORE, flew on space shuttle Challenger on STS mission 51-F. Tony took a handheld 2-meter transceiver and a Robot 1200 slow-scan television scan converter along with him on his trip. Tony used this equipment to make voice contacts with amateur radio operators on the ground, and to send and receive slow-scan television (SSTV) pictures from the Space Shuttle.
My slow-scan television equipment at the time was homebuilt. In 1980, prior to becoming an amateur radio operator (and while still in high school) I built an SSTV monitor using an old Heathkit oscilloscope, and an SSTV adapter circuit developed by W7ABW. The scope's 5BP1 CRT was replaced with a 5UP7, which had the long persistence phosphor needed for SSTV reception. During my time as an SSTV "SWL", I used my Hammarlund receiver and homebuilt equipment to receive slow-scan television images from around the globe. I especially enjoyed the Voyager 1 flyby of the planet Saturn in 1980, the images of which were relayed via SSTV by W6VIO at the Jet Propulsion Lab, Pasadena, California.
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Some examples of slow-scan television circa 1980. The first two images were sent by WA4NLV in Raleigh, North Carolina. Notice the Apple II computer generated graphics! The image of Johnny Carson was sent to N2BJW in Elmira, New York from KG4I in Birmingham, Alabama on June 14, 1980.
Not long after completing the W7ABW SSTV adapter, I began construction of a higher quality Robot 70A SSTV monitor. However, the SSTV standards began to change drastically in the early 1980s, and my homebuilt P7 SSTV gear soon became obsolete.
During the Space Shuttle Challenger STS-51F mission, slow-scan television transmissions were received at KD2BD on a Yaesu FT-227R 2-meter FM transceiver (purchased at a local hamfest), and recorded on an open reel tape recorder for later processing. The low resolution black-and-white (actually frame sequential color) SSTV images transmitted by the Space Shuttle were viewed on my legacy SSTV equipment. About ten years later, some of the higher resolution color SSTV images captured on my recordings were successfully decoded and displayed on a PC.
This color slow-scan television image was received from the Space Shuttle Challenger in August, 1985. It shows astronaut Gordon Fullerton wearing headphones in the lower right against the front windows of the Space Shuttle during mission STS-51F/Spacelab 2. Some papers can be seen above Gordon's head towards the top of the image, along with a keyboard and some instrumentation along the left.
The second image shows astronaut Dr. Tony England, W0ORE. Both images were received on a frequency of 145.550 MHz FM using an omni-directional antenna in my attic and a low-noise preamplifier of my own design.
This QSL card officially verifies my reception of amateur radio signals from the Space Shuttle Challenger during mission STS-51F, and commemorates my participation in this early SAREX experiment.
The STS-51F mission inspired a strong interest in satellite communications. As packet radio began to become popular around 1987, an MFJ-1270B packet radio terminal node controller was purchased (after much arm-twisting from many of the local amateurs). This TNC was used in conjunction with the then-popular Commodore 64 home computer to communicate using the AX.25 protocol. This permitted access to local packet radio bulletin board systems, including the KA2QHD Unix-based Packet Radio <--> UUCP Gateway, that opened the door to the world of Usenet newsgroups and Internet-style e-mail in a completely wireless manner. Terminal emulation software was written for the C-64, and the skill of writing code in 6510 machine language was acquired in the process.
Several hours before the TNC arrived, an AFSK demodulator was constructed for the purpose of decoding news bulletins and ASCII telemetry sent by the UoSAT-OSCAR-9 and UoSAT-OSCAR-11 satellites. Over time, simple satellite orbital prediction software was written for the C-64 using reference orbit data sent by W1AW in CW. Telemetry capture and analysis software for the OSCAR-9 and 11 satellites was created and eventually donated to AMSAT-NA in support of the Amateur Satellite Program.
My strong interest in the Amateur Space Program provided inspiration in November 1987 to create an electronic newsletter for like-minded individuals. Circulation was primarily via the Amateur Packet Radio Network, and via the Internet. The newsletter was called SpaceNews, and weekly publication ran for over 13 years. Reader interest was so great that editions of SpaceNews were made available in English, French, Spanish, German, Portuguese, and Chinese.
The space station Mir began hosting amateur radio operations from several visitors and inhabitants of the Russian outpost. Operations included voice contacts with stations on the ground, packet radio, and slow-scan television. Several inhabitants of Mir read my SpaceNews reports while living and working in space.
Msg # Stat Date Time To From @ BBS Subject 42 P 91/03/09 04:37 U2MIR KA1SU Hello Musa 41 PR 91/03/09 03:21 ALL U2MIR qsl 40 PR 91/03/09 03:02 U2MIR VO1SA Greetings 39 PR 91/03/09 03:00 U2MIR VO1XC GREETINGS 38 PR 91/03/09 02:54 U2MIR KI4TD GREETINGS 37 PR 91/03/09 02:51 U2MIR KC4UZA hello agai 36 PR 91/03/09 01:31 U2MIR F3NW TOMORROW 35 PR 91/03/08 20:37 U2MIR TR8CA * SpaceNews 04-Mar-91 * 34 PR 91/03/08 20:36 U2MIR TR8CA PHOTOS 33 P 91/03/08 16:30 KJ9U U2MIR LIST 02.03.91 2538 Bytes free Next message Number 43 |
SpaceNews appears as message 35 in the Mir Personal Message System (PMS) listing above. The R in the status column means the message was successfully read by Cosmonaut Musa Manarov, who was stationed on Mir at the time.
Nine years into publication, SpaceNews earned a Magellan Award from the McKinley Group's professional editorial team.
In 1991, PREDICT satellite tracking and orbital prediction software development began using a Commodore 64 home computer.
PREDICT software use and development continues to this day. The preferred computing platform is now the Linux operating system. Today, PREDICT has found homes at such places as NASA, JPL, Stanford University, Cornell University, and the U.S. Naval Academy. It even talks to you while you keep your eyes toward the sky during visual satellite passes.
Several other software projects, including SPLAT! (pictured above) are currently under active development. All are designed for applications in the field of RF/wireless communications.
As my interest in satellites and computers continued, I purchased a Yaesu FT-726R multimode VHF/UHF transceiver from a local ham.
I soon grew a burning desire to decode the "buzzing" BPSK signals I was able to receive from the AMSAT-OSCAR-16, WEBERSAT-OSCAR-18, LUSAT-OSCAR-19, and FUJI-OSCAR-20 satellites using this transceiver. A crude BPSK demodulator was designed and interfaced with the MFJ-1270B TNC and FT-726R. Following the success of this proof-of-concept demodulator, a much more sophisticated Pacsat modem was developed and later completed in 1993. Upon completion, it was dubbed the "KD2BD Pacsat Modem".
I published a ten page paper describing the KD2BD Pacsat Modem's design in the August 1994 issue of QEX magazine. The design was subsequently published in The AMSAT Journal, and the ARRL's Packet: Speed, More Speed, and Applications, first edition. A copy of these articles is available on-line.
The "Mir Achievement Award" pictured below was earned after successfully establishing two-way UHF voice and VHF packet radio contact with astronaut and fellow ham radio operator Michael Foale, KB5UAC while he was stationed onboard the Russian space station Mir. These contacts took place in August and September 1997.
A lot of excitement surrounded Mir's slow-scan television transmissions. The following color slow-scan television image transmitted in Robot 36 mode shows a spectacular view of the Earth as seen out of one of windows of the Russian space station Mir during a pass over southeastern Canada on December 26, 1998. It was received at my home on a frequency of 145.985 MHz FM using a Yaesu FT-726R transceiver, and a roof mounted 8-element yagi antenna about the size of a TV antenna.
The next image shows Mir just prior to crossing the terminator and entering into the Earth's shadow. Mir appears very bright against the dark earth below. This image was received on January 31, 1999 on a frequency of 145.985 MHz. Mir was actually visible in the evening sky over New Jersey when this image was transmitted by the spacecraft.
In 1994 I accepted a position as columnist for Satellite Times magazine. My responsibilities included writing a regular column on the subject of Amateur Radio Satellites, as well as several special feature articles. In 1997, an issue of the magazine was used as a "set decoration" in the movie Conspiracy Theory, starring Mel Gibson and Julia Roberts.
On September 11, 1994, I was the featured guest on "Spectrum" (Communications Technology News and Features "From DC to Light"), broadcast world-wide on short wave from WWCR, Nashville, Tennessee, U.S.A.
Several weeks later I was the featured guest on "Bridging Gaps", WBJB-FM, Lincroft, N.J.
In October 1996, I was a guest speaker at the Grove Communications Expo in Atlanta, Georgia. The topic of discussion: Amateur Radio Satellites.
I was invited to give presentations to nearly every amateur radio club in the local area.
To date, I have had technical articles published in a number of books and periodicals, including:
In August 1997, I successfully developed a working 9600 baud FSK modem for OSCAR satellite use in just one week's time. Working in conjunction with the MFJ-1270B and FT-726R, this modem provided access to the UoSAT-OSCAR-22, KITSAT-OSCAR-23, and KITSAT-OSCAR-25 digital satellites. My circuit design was published in Satellite Times magazine. A re-print of the article may be read on-line.
In October 1997, I was featured on the front cover of CQ VHF magazine.
In January 1998, I used my Pacsat ground station to exchange images and text messages with Andre Phillips, VK0MAP, who was stationed at the South Pole:
To : KD2BD From: VK0MAP Time: 025819UTC Date: 22 Jan 1998 ----------------- South Pole Station Antarctica Hello John, Thanks for the brief mention in SpaceNews and it would have been fun to chat direct with Ron when he was down here. Most of your article comments apply to this station as well. The rig here is a Kenwood TS-790A with PacComm Tiny 2. It all works very nicely I must say. The up/downlink antennas are a couple of Lindenblads fashioned from no. 8 fencing wire and they do an excellent job. I get a solid 5+ minutes of connect time per pass. At the Pole UO-22, KO-25 and POSAT all rise to an elevation of 34 degrees, and KO-23 to 12 degrees. Power is not a problem as Pole Station is an extremely well equipped scientific* Antarctic base, and also with a very agreeable social atmosphere; it's a fun place (*unlike many Antarctic bases whose role is mostly political). I'll be uploading more information over the next few days. I'm keen to promote Amateur satellite communications and fielding questions from kids is one way to do it. If you know of any teachers who would like to forward questions then I'll do my best to answer 'em briefly... As I write there is a Herc taking off outside. They pass only a few hundred feet from my window and are an impressive sight, especially when occasionally generating condensation trails right from ground level. We get 2-5 Herc flights in per day. Do you know John Arnold's callsign, and whether he's active on pacsats at present (he was in '94-'96)? 73's Andre VK0MAP/VK5AAP/ZL3AW Andre Phillips Dept of Astrophysics & Optics UNSW, Sydney, NSW Australia, 2052 ph: (61 2) 9385-5003, fax: 9385-6060 WWW: http://www.phys.unsw.edu.au/astro.html (UNSW Astrophysics) http://www.phys.unsw.edu.au/~mcba/aasto (AASTO project) http://www.phys.unsw.edu.au/~mgb/jacara.html (Antarctic astronomy) |
For over ten years I have been involved in Amateur Television (ATV), having engineered the 70-cm ATV Repeater System at Brookdale Community College, in Lincroft, New Jersey. The repeater is used to relay ATV signals throughout the North Jersey exterior area, and also provides re-transmissions of NASA Television programming during U.S. Space Shuttle missions.
A number of the repeater's current subsystems were designed by myself. These subsystems include the aural and visual exciters, the video modulator, and the video operated relay circuitry located within the repeater's controller. The video modulator has become quite popular in ATV circles, and is even featured in the latest edition of The ARRL Image Communications Handbook, by Dr. Ralph Taggart, WB8DQT. The video operated relay was published in the Spring 2000 issue of Amateur Television Quarterly.
I have been serving as advisor for the Brookdale Amateur Radio Club since 1991, and help to save lives and property as an active member of the National Weather Service's Skywarn program.
My current HF station is completely homebuilt. It consists of an Elecraft K2/100 (serial #3563) 100-watt SSB/CW transceiver powered by a 13.8 volt 20 amp regulated D.C. power supply of my own design. The K2/100 transceiver was built in June 2003. My first contact was with M0RAD in Stratford-Upon-Avon, England (Land of Shakespear). My farthest contact so far has been with VQ9MJ in Diego Garcia.
In recent years, I have become quite involved in the art and science of making precise frequency measurements of distant radio signals using equipment and techniques of my own design. I am a frequent participant in Frequency Measuring Tests sponsored by the ARRL, K5CM, and The Midwest VHF/UHF Society.
The following audio clips capture some memorable moments in KD2BD radio history:
For more information on the Amateur Radio Service, please visit the web site of the American Radio Relay League.
VY 73 ES CUL DE KD2BD
No animals were harmed, nor any Micro$oft products used in the creation or distribution of this page.
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John A. Magliacane Amateur Radio Operator: KD2BD Open Source Software Developer Internet Advocate Since 1987 Linux Advocate Since 1994 |
