Preface

It is said that the growth of any nation is directly related to the percentage of Hams in it. Japan, the most Ham populated country in the world with 1 million Hams in it, according to a 1995 survey, is the living proof. I spent those most fruitful years of my life in Ham Radio – I enjoyed it. The basic driving force was certainly my passion for electronics. As I interacted more with this royal hobby, I learnt that there is discipline in it, patriotism in it, love for humanity and Nature in it and an unending quest for answers also are in it. It can be defined as a spare time hobby of people interested in radio communication techniques forming into an international network of friends and living committed to the growth of humanity and Science. It is an unending ‘ragchew’; it is experiments and innovation; it is polishing personality and growing more global; it is also relentless service of the society and the nation. As you switch on your rig, after acquiring proper license, you also will experience the discipline which all Hams follow, the respect with which each other behaves and the spirit of equality that prevails wherever Hams are.

In Part 1, I have given a brief account of Ham activities in the south, and a briefing on those first seven Ham Fests (all of which I attended in full). I think that without an idea on the community into which one intends to join, it will be hazardous to think of becoming a Ham. It is about the last quarter of the previous 20^th century that I speak of.

Hams have a bright record of public service. Part 2 gives you a series of true stories, all intended to give the reader glimpses into those silent possibilities where a Ham perfectly fits in any society. In 1992, I wrote these stories in a Malayalam Science magazine, ‘Electronics for Everybody’. The entire texts are reproduced in Part 2 of this book, as it was.  

It is an amateur who first used Short Wave, it is an amateur who came out with SSB and various modulation techniques. At a time when a 200 meters range Citizen Band Radio was sold for Rs. 12,000 or more in India, Amateurs developed Short Wave transmitters that cover the entire south India and more for Rs. 200/-. My enthusiasm to share my shack experiences with others was the motive behind the much appraised article series, ‘Gateway to Ham Radio’. Shri B Soman Nair, Chief Editor of the magazine, ‘Electronics for Everybody’ solemnly invited me to write in the magazine and in January 1995 the first chapter of Gateway to Ham Radio was published; it continued up to 1998. This book truly owes greatly to this great man – Shri. B Soman Nair.

Even after 18 years, I used to get mails requesting for a copy of it. But it took this much time for me to realize that it was a useful piece of sharing for budding Hams. All that I remember was that each article had consumed a minimum of 10 days to prepare it. There is no surprise if a man who has done his academic studies in English language and literature needed so long a time for even simple chapters. Part 3, which is the heart of this book, owes greatly to OM Jayachandran VU3 BWB (Ernakulam) and OM Madhu A65DE, from Vaikom (Kerala). Unless they had made the old magazine copies available, reproduction of the texts would not have been possible at all.

In Part 4, I have given the syllabus for ASOC Exams, Samples questions and Answers, formalities required for an exam and finally details of Amateur Radio License fee and its application formalities.

Thank you all my Guides, Masters and Friends who have helped me prepare this book. I do not believe that this is ever a befitting expression of my gratitude to Ham Radio, for all that I have received from it; this is only a squirrels share. I dedicate this book to all those First Generation Senior Hams, who could build this hobby into a way of life for all who have concern for oneself and the society in which we live.

Thank you

Joseph Mattappally

  

Part 1 - My SWL Days

It all began in 1982, in which I happened to read a Sunday Supplement exposure (Malayala Manorama – Malayalam Daily) on Amateur Radio, written by one James Kalassery. He had written that Ham Radio is the most royal of all hobbies and it is a network of licensed Amateurs from around the world, which hasn’t any restrictions of age, gender, caste, creed or social status. At that time, I was only 30 and was managing a electronic equipment’s servicing and spare parts selling shop in my nearest town – Ponkunnam. I contacted OM James Kalassery VU2 ARL (Kochi), the writer, from whom I got the initial guidelines (OM, means ‘Old Man’ and it is how Hams address all licensees). KARL (Kerala Amateur Radio League), founded by James, based at Kochi was the first Ham’s Club that I joined. The first Ham event I attended was the Second All India Amateur Radio Conference organized at Kochi. Amateur Radio Society of India (ARSI) and Federation of Amateur Radio Societies in India (FARSI) were the National level organizations of Hams at that time. They later merged into one (ARSI) and continue to be the only society in India approved by IARU. The memento I got during the ‘82 Kochi Conference is still in my keep. Though the Conference was packed with senior celebrities from around India, it was more or less an assembly of strangers for me – I was not even a good listener at that time. But I still remember blind Om Chakravarthy (VU2TTC) from Tamil Nadu; I still remember the enthusiasm with which those celebrities hugged each other; I sill remember the stall demonstrating microprocessors; I still remember the Eyeball QSO contest held there.

Om Abraham VU2 AHM, 25 kms. away at Pala, was my nearest Ham. Others in the district were a few committed experts - OM Dr VK Kuriakose (VU2 VKK), OM TG Guhan Menon (VU2 TG) and Om DR PP Kurian (VU2 PP). I got all sorts of helps from all these fore runners in this district. I got my 2^nd grade license in 1984 and my first grade in 1986. When I got my grade 2, the total no. Hams in Kerala was below 150. By that time there emerged a batch of 2^nd generation active Hams, all of who were mostly home brewers. A lot of circuits were shared at that time. Taking lavishly from all these concepts and adding more from OM Guhan, I too developed a 12 V - 5 W - 40M transmitter in 1990 with a D882 transistor in the final. It cost hardly Rs. 1000/-, even when it was set in a beautiful cabinet.

My interaction with HRG (Ham Radio Guild) founded by OM Mukund (VU2DRL) helped me to explore Ham Radio further and most of my field experiences like Popular Car Ralley, Operation pilgrimage at Sabarimala and Velankanni, Field Days, QSL Beareau service, Emergency traffics, Trans India Contest, events like Wireless ’91, JOTAs (Jamboree on the Air) owe to HRG.

Almost until 1990, every year, Amateur Radio Clubs all around used to organize yearly get togethers in which people from various places assembled for eyeball QSOs (meeting persons face to face). There were exhibitions, technical talks and Rig experiments. One thing I noticed – each Club behaved more or less like a dissident from the main stream. Though home brewing is the backbone spirit of Amateur Radio, most of the high profile Clubs and conventions were hanging around Commercial Equipment and hi-tech discourses. Not much space was allotted to QRP home brewers.

The Story of Ham Fests in India

Revisiting the growth of Ham Radio in Kerala, will definitely help the readers to understand the features of this hobby better. Almost all the Clubs in Kerala took shape in or after 1980. The Nanthancode Electronics Club (Trivandrum), which organized the first ASOC exam in Kerala, was the first Hams Club in the State; OM Hari VU2 BY from Kozhikode was the first Ham in the State. As years passed by, a heavy flow of enthusiasts filled the country. A good number of Parliamentarians also were Hams at that time, may be thanks to our former Prime Minister, Om Rajiv Gandhi (VU2 RG). As a result, more local Hams Associations took shape and home brewing also grew intensely. It was a time in which ASOC exams were held on a regular basis all over the South. Early Clubs, as I understood their activities, were trying to outshine another, even though none of them used the word competition. They did not fundamentally promote home brewing but basically continued to be a creamy layer, with enough grains in it.

It was at such a scenario that a few Hams – OM Sharma VU2LV, OM Natan VU2 KGN and OM Dr Jayakumar VU2JKR convened a meeting of Kerala Hams at Nithya Hotel, Kottayam, in 1991. The purpose was a new Association beyond the existing Club holdings. The organizers assumed that even KARL, the only state wise Hams association of the times, does not function up to everybody’s expectations. But the participants took this chance to share their views on these warring Amateur Radio Associations and the difficulties home brewers face. Everybody agreed to the point that inter-club relations should be improved highly and home brewing should be promoted much more. The meeting unanimously agreed to appoint a three members ‘Kerala Amateur Radio Clubs Coordination Committee’, in which Om Joseph VU2JLX, OM Jose VU2 JKV and myself were members. 

The first thing that the committee decided do was to work for the promotion of home brewers thus bringing them all under one umbrella. The new Committee found that intensive efforts are necessary to do this. That was the prime reason behind launching of Ham Information Net (Hinet), which the committee initiated on 40 meters. This happened in August 1991. It began functioning on 7065 Khz. between 8 AM and 8.30 AM on all Sundays without break. Joseph (VU2JLX) and myself (both home brewers) were controlling the net regularly. Gradually it paved way to Radio Round Tables, exclusive discussions on pre selected topics, headed by experienced Hams and some times scripted and sponsored by Ham Clubs. Radio Round Tables timing was 7.15 AM on Hinet frequency, on Sundays. On some occasions it continued even after Hinet. Within a short span, Hinet became the centre of South Indian home brewing activities and the first gateway to SWLs. Gradually, on-the-air special classes were organized on various home brewing strategies under well experienced senior Hams. The focus of the co-ordination committee happened to be the promotion of budding hams at the lower layer.

Slowly, the committee found that on-the-air audio demonstrations are not enough. Many people needed live demonstrations. We never wanted to leave anybody astray – a field day was planned. Field days, as such, were mostly limited to eyeballs, a few antenna/propagation experiments, local food service experiences and chats. They were more or less study picnics. No, that was not what we were thinking of. We definitely wanted more time to share shack techniques like PCB designing, etching, drilling, soldering, coil winding, rectifier assembling, modulation transformer winding, mounting ICs and transistors, SWR matching, frequency counter assembling, antenna designing, receivers, BFOs Oscillators, operational etiquettes and much more…. After prolonged discussions, we decided to make this a two days event. I was authorized to coordinate the event – a Home brewer’s workshop. The whole Hinet family took the idea seriously. Discussions went on for a befitting name for this event. Home brewer’s Meet, Hams’ Festival, a lot of proposals were discussed. The title ‘Ham’s Festival’ was finally approved but as the event closed in, the name became Hamfest.

One of our decisions we eventually made in this regard was that the merits of this event should not be attributed to any single person, and all the way a common spirit was maintained and it is this energy of unity that paved the way for Hamfest India later. Money was the main villain. Our concept was to render the support free or at the maximum at actual food and accommodation expenses. One name I wish to remember at this time is that of who came forward offering their support. Thanks to Mukund (VU2DRL), then secretary of Ham Radio Guild, Kochi, all participants were free to pay only an amount of their pleasure and Ham Radio Guild filled the deficit amount needed. It was they who brought the nametags printed, ‘Hamfest ‘91’ which was the only material on which the event name was printed.

Hamfest ‘91

The first Hamfest began with a welcome session in Pius 10^th Higher Secondary School, Kuttikanam on……. It was Om Menon VU2MAH from Quilon, the oldest Ham present there, who presided the first Session. After initial formalities, all moved to the Gov.t Guest House at Kuttikanam, a hill top tourist centre in Idukki dist. on Kottayam - Kumali Highway on the Eastern Hill ranges. The whole team as planned before split into various stalls/groups, some demonstrating home brewing techniques, some selling kits and some holding question answer sessions. Senior experienced Hams like Om Gopi VU2 EGM, OM Ravi VU2 RDN, Mukund VU2RDL lead the sessions.

All the participants irrespective of status, ate together, slept together and thought together. It was an unforgettable experience. During the closing session, none could hold their appreciation for the event. It was simple, elegant and well organized, where Hams came and joined on their individual standing, irrespective of their club or society bindings and collectively worked in the true spirit of the hobby. Hamfest ’91 was a grand success! Everybody wanted this event to continue every year, in the same spirit of togetherness. In the final get together, Om Gopi VU2 EGM was unanimously appointed Gen. Convener for Hamfest 1992.

Hamfest ‘92

I kept my promise to Om Gopi and worked for the event as Programmes Coordinator. Hamfest ’92 was a whole year event for the various committees and members working for it. It was organized at Alwaye on October 10th and 11^th. Reception and registrants service was managed by a committee under Ravi (VU2RDN), Food and accommodation was managed by a committee headed by Joseph VU2 JLX, Souvenir Committee was headed by Mukund (VU2DRL) and Awards committee was headed by Sadhujan (VU2PGS). The registration fee for SWLs were just Rs. 25/-. From 1992 on, special event call signs were allotted to the event and train travel concessions also were made available to the delegates.

Hamfest ‘92 too was a stunning success; it could raise many eyebrows. A beautiful Souvenir was published and the entire programmes were video recorded. On the first day evening there were cultural entertainment programs including a magic show by a fellow Ham OM Joy VU2MIE. The whole day of 11the was exclusively reserved for training in home brewing techniques, from PCB making to transformer winding. Registrants were divided into teams of 20, each under an experienced Ham. Round table discussions that cleared the doubts of SWLs also were part of it. Hamfest ’92 honoured every one who contributed to the growth of Ham Radio in India and Certificates of acknowledgment were awarded to Hams and SWLs. An essay competition on ‘Relevance of Ham Radio in Society’ was held for College students. Awards sponsors were Trivandrum Amateur Radio Club, National Institute of Ham Radio, Kerala Amateur Radio League and Quilon Amateur Radio Club. The best collection of QSL Cards was honoured by Thodupuzha Amateur Radio Club while Queen city contest awards were sponsored by NIAR. The best stall award sponsored by KARL was bagged by Moni VU2ITI, the best home brewer award was bagged by Vasanth VU2 VWN, best net controller award was bagged by Moni VU2HSM. There were gadgets sales sections, junk sales stalls, books and periodicals sales stalls etc. also at the venue. On Sunday, an ASOC exam was held in this connection. The event also raised some money to support the family of a diseased Ham – OM Bhasi VU2UCY. South Indian Film star Charu Hasan VU2 SCU was one among the celebrities who attended the Fest. More than 200 Hams and 400 SWLs attended the event. OM Gopi Gen. Convenor of Hamfest ’92 received wide applause from all around.

In he General Body meeting held, OM Premchand VU2RPC from Tamil Nadu was appointed Gen. Convenor for the upcoming Hamfest and the hosting Club for HF ’93 became Kovilpatti Amateur Radio Club. Our dream of shaping Hamfest into a South Indian event, thus became came true.

Hamfest 93

The state of TN, then the most Ham populated State in India took it as a challenge. Om Madhu VU2MUD from Mysore already had agreed to host the 1994 Hamfest. Live demonstration stalls, elaborate flee/junk market, assembled/important equipment /sales display stalls, presence of celebrities, awarding commendable contributions, prizes to contest winners…… everything went on among wide applause. 

During Hamfest ’93, I also received an exclusive presentation – Ham of the Year for 1992 Award declared by Ham Radio Guild, which included – a citation and a cash of Rs. 5000/-. As was previously arranged, the Mysore Hams came forward to host Hamfest ’94 in Mysore.

Hamfest ‘94

 

According to a media report on Hamfest ’94, the fourth South Indian Ham event, it was celebrated in a fully air conditioned auditorium - Karnataka Kalamandir, Mysore - on 17^th and 18^th of September 1994. From around the nation, some 350 Amateurs attended the event. The event was organized by a team headed by Om Madhukar VU2MUD (Gen. Convenor) and OM Shankar Prasad VU2 PSK (joint Convener). The fest was inaugurated by Shri Nilkandaraj IAS, Mysore Divisional Commissioner, at 10.30 AM on 17^th. The inaugural meeting was presided by Mrs Jija S Harisingh IPS, Southern Range DIG of Police. The Keynote address was delivered by Shri YS Rao CEO of Max India Ltd. The dignitaries who addressed the delegates appreciated those distinct features of Ham Radio and Mrs Jija requested Hams to come forward in support of the Police force in suppressing anti social uprisings/elements.

In the technical Session of the afternoon, OM U Mohandas VU2 DAS talked on Packet Radio, OM Adolf VU2 AF talked on Propagation and OM Joseph Mattappally, VU2 JIM on Homebrewing. In the evening at 5 PM Hamfest General Body, which was presided by OM Madhukar, the Gen Convenor, was convened. OM Adoph Shephard VU2 AF from Mumbai was appointed Gen. Convenor for the following Hamfest. The next venue for the event also was decided to be Mumbai. Knowing that the event has become National, OM Joseph Mattappally VU2 JIM suggested that the name be changed to Hamfest India and the meeting unanimously agreed to the idea. After the General Body, a lot of cultural programs were staged in the auditorium. The next day was fully planned for contests, displays, eyeballs, awards and discussions on ham related topics. The final meeting was presided by Om Adolph, VU2AF. Awards and Plaques of Trans India contest and JIM-HRG contest awards were presented by Om Giriraj VU2 GX. A lot of popular clubs like IIH Bangalore, HRG Kochi and a lot of Home brewers also had hosted stalls in the fest. Commercial Companies like UMS and Digitronics also were there in the Fest venue. Both the Convenor and the joint convener were appreciated widely for the perfect plan with which they organized the Fest.

Hamfest ‘95

Hamfest ’95 in Mumbai was a milestone in the growth of Hamfests. The three days Prefests in all the 4 Zones in India was an added attraction. OM Ponnuswai VU2 APS was in charge of the South Zone and he organized a 3 days workshop in Erode on 25^th, 26^th and 27^th of August 1995 with the slogan, ‘Equip all Shacks’. HFI ’95 was kicked off with the King City contests in September. Here is the full translation of a media news coverage.

‘The National Festival of Hams in India, Hamfest India ’95 was appropriately celebrated in Tejpal Auditorium in Central Mumbai on 28^th and 29^th of December 1995. It was this auditorium that witnessed historical events like formation of Indian National Congress and declaration of Quit India Movement. This event was the biggest gathering of Hams in India – it had more than 1000 registrants, including those from Dx. HFI ’95 programmes were streamed live through TV and Radio. Other media also reported it with due importance. It was attended by International Telecommunication Union (ITU) representatives and Gov.t of India officials like Shri. Vittal IAS. Around 15 sub-committees were working behind HFI’95. Elaborate stalls of States and worldwide equipment/components manufacturers were all reserved for the event. The best home brewer award of Rs. 50,000/- and the Man of the Fest  award for the winner of the on the spot quiz contest, all were added attractions of  Hamfest India ‘95.

Rich talks on various aspects of Ham Radio definitely took the delegates in awe. In the Gen. Body held in the evening, the delegates talked on the difficulties Hams face with regard to Gov.t support. Shri P K Gulatthi, Wireless Advisor to Govt. of India assured the delegates to avoid unnecessary delay in issue of licenses and reduce import formalities on Ham equipment.

It was quite unanimously that the delegates appointed OM Avinash Mihshra VU2 EM as Gen. Convenor for HFI 96, the venue of which was declared to be Kolkata. Among wide applause, OM Joseph Mattappally VU2JIM invited him to the dais in the traditional style and spoke congratulating the new Gen. Convener. Replying to the felicitations OM Mishra promised that the next Hamfest also would be giving priority to Homebrew spectrum. Awards and certificates were presented on the second day afternoon. Shri Sargath Sing, ITU representative presented the awards. In the King City contest five out of nine prizes were bagged by Kerala and the hero was OM Sunil VU2UKR. A memorable programme of the event was passing the ITU flag to ARSI in honour of the commendable services they have rendered to Ham Radio. OM Mishra, who had already taken charge of the dais, appreciated OM Adolph for the beautiful performance, team HFI ‘95 presented in Mumbai and that quite perfectly. As a mark of gratitude OM Mishra presented him a beautiful bouquet. Passing the official flag of Hamfest India was the last ceremony of the day. Before the fest was called off, all the delegates stood hand in hand and repeated the community pledge.  The organizers also had issued a special souvenir and All India Hams Telephone Directory.

Hamfest India ‘96

Adding another colourful feather on the cap of Hamdom, HFI ’96 was elaborately celebrated in Salt Lake stadium Kolkata, on 19^th 20^th and 21^st of December 1996. Of all the Hamfests this event was different with the highest no. of Dx delegates ever. The entire 500 beds dormitory there was full with Hams and SWLs from across India. Registration fee for Hams was Rs. 500 and for SWLs it was Rs.200. It included charges for food too. There also was a total no. of around 900 registrants. Look at the media report: Inaugurating the event, which the Kolkata media covered in full, ‘Prof. Divakar Ven, Director of the Acharya Jagadish Chandra Bose Institute, detailed the past 100 years of Radio and innovations with it.  The whole event was dedicated to late pride of India, Acharya Jagadish Chandra Bose. There were very informative and nourishing talks on different topics, Joy City contests, cultural programmes of Doordarshan artists, exhibitions, conducted tours, sales stalls (Dx and VU), commercial equipment display, mementoes distribution etc. Everything added together, HFI ’96 was one of the major events organized in W. Bengal. The Gen. Body there discussed in detail prevailing problems that Hams in India face. The Gen. Body decided to appoint a committee to see into it and work for a satisfactory remedy. It was because of the joint effort and call of Kerala Hams, Kerala got a 3^rd chance to host the event. HFI ’97 was decided at Kochi. Among wide applause, OM Joseph Mattappally, on behalf of Kerala Hams, received the official documents and HFI Flag from OM Avinash Mishra. In his brief thanks giving address, OM Joseph Mattappally appreciated the arrangements done in Kolkotta and congratulated the organizing committee for the tremendous effort they put in it.’

The days were unforgettable for me too. At Kolkata, I could meet St. Mother Teresa, alive. She was so weak when I saw her. Still I remember that the sisters there got two signed mementos for me. She passed away within a year.

Hamfest ‘97

The first thing OM Suresh, the Gene. Convener, did was appointing a 101 members volunteers team and a dozen of expert committees, intended to manage different activities. Radio pilgrimage was a unique event in connection with the Kochi Hamfest. Five days prior to the Fest days, were reserved for tour packages for delegates from outside the state. Important activities proposed in the event were presentation of important technical papers, training in assembling of small gadgets like VFOs, QRPs, demo.s on Packet/Pactor reception, Internet usage information, exhibition and sale of old and new components/equipment, display and sale of books and gadgets, Radio pilgrimage, contest for prestigious JC Bose award and so on.

Here is the media report on HFI’97: ‘The 7^th National meeting of Amateurs in electronics was celebrated in Renewal Centre Kochi on December 20^th and 21^st, 1997. There were technical workshops, seminars, group discussions, sale stalls, junk market, periodicals display, live demos on digital communication and changing amateur radio strategies etc. Internet booth was an added attraction. On the first day the functions started as OM Avinash Mishra VU2 EM hoisted the flag. OM Narayan VU2 NYR delivered the Welcome Speech and Ganesh VU2TS gave the Presidential Address. Shri V J Pappu, Pro-Vice Chancellor of Kochin University, was the Chief Guest who lighted the lamp and did the inaugural address. The souvenir was released by OM Saharuddin VU2SDN and OM Suresh VU2 SUO delivered vote of thanks.   

At 11’ O clock OM Saad Ali and at 12’O Clock OM Saharuddin talked on VHF activities. At 3’O Clock OM George VU2 GT talked on Homebrewing VHF Antennas. At 4.45 PM OM Jayaram VU2 JN talked on homebrewing QROs. At 5.30 PM the General Body was called and it decided the next Hamfest Venue to be Bangalore and the Gen. Convener to be RCR Chandru VU2 RCR. From 9 PM onwards on the first day, entertainment Programs by ‘Waves’ Trichur added to the glamour of the event.

The second day began with ARSI Gen. Body Meeting at 8.30 AM. At 10’O Clock, Ganesh VU2 TS talked on Satellite Communication and at 11.30 OM Adolf anchored an on the spot Quiz competition, in which OM Madhukar VU2MUD won. At 12.30 OM AO Guntu Rao talked on modifying BEL transceivers. At 2’O Clock Ham Radio Guild distributed Trans-India Contest Awards. In the closing meeting OM Suresh VU2 SUO, Gen Convener, spoke to the delegates and he appreciated the grandeur of support he received from fellow Amateurs. Last item of the event was distribution of Queen city contest Awards and Certificates of Honour to distinguished promoters of the hobby.

Chapter 1 Radio Signals and the Ionosphere

 The Growth of Communication Electronics

The puzzling mysteries of the Universe continue to be so, even though humans began their attempt to explore or expose it from time immemorial. As humanity grew into cultures, sects and civilisations, studies and researches also grew into branches and now the most important branch of all Sciences have come to be Electronics. Electronics is defined as the science of controlling electrical energy electrically, in which the electrons have a fundamental role. Lately, the explosion in Communication Electronics has changed the entire globe into one village - causing a great paradigm shift in every area of social life.

Novelist Arthur C Clarke, a popular science fiction writer (author of the much acclaimed novel ‘A Space Odyssey’ - an voyage to Jupiter) hinted in his short story 'The Sentinel’ that future communication would be artificial satellites controlled. The invention of Telegraph by Samuel Morse, was certainly the first step and the invention of Telephone by Alexander Graham Bell turned out to be a Milestone. The Radio, introduced by Guglielmo Marconi, an Italian electrical engineer, made the evolution revolutionary. As the Russian Satellite Sputnik set its' feet in the space in 1958, communication technology and concerned strategies took another giant shift. The US owned Explorer 1 which also appeared in space before long virtually changed the dimension of our expectations too. 

Even though SCORE (Signal Communications by Orbiting Relay Equipment) owned by US Air Force was the first satellite to handle a message to a distant place, it is 'Telstar’ designed and launched by Bell Telephone Laboratories (New Jersey), the very laboratory from which transistors came out, that got the credit of being the first communication satellite. SCORE captured world attention by broadcasting a Christmas message from U.S. President Dwight D. Eisenhower to Europe, in 1958, via short wave radio and further through an on-board tape recorder. Today, the entire space around the globe is filled with multitudes of radio signals from satellites, most of them engaged in communication. In another words, we live in an ocean of radio waves. 

Always Amateurs had vital roles in inventions - many people experimented with radio frequencies too. Short Wave, SSB.... all are contributions of similar Amateurs. This book, ‘Gateway to Ham Radio' intends to give an opening to all Amateurs who love to enter a world of innovators, known by the title 'Ham Radio Operators'. 

Radio Signals

The impact of a sound in the atmosphere is just like a rubble thrown into still water - it causes a chain of waves. If the three dimension waves in the water can be seen, the multi dimensional waves that sound causes in the Air are invisible. It is the number of cycles that a particular wave forms in a second that is counted through the unit, frequency. A cycle, as its' name implies, is a circle. When a number of cycles are to be represented, circle is not a comfortable picture to show continuity. So a cycle is always shown like that seen in the picture C-1/1

Here, a circle is shown in a cycle pattern and it begins at 0⁰ and through 90⁰, 180⁰ and 270⁰ it reaches 360⁰ or again back to 0⁰, from where it continues to another cycle of the same configuration. Any cycle has qualities of amplitude and wave length. Suppose we hear a constant whistling sound from an amplifier. As we raise the volume what that changes is the amplitude of the signal. Suppose a man and a woman say good morning in a moderate volume, it is the number of cycles their sounds make in a second that vary. It is measured in frequency - number of cycles per second. Normally male voice is comparatively low in frequency. 

C-1/2A
Frequency Range	Name	Short Name
3KHz – 30 KHz	Very Low Frequency	VLF
30 KHz - 300 KHz	Low Frequency	LF
300 KHz - 3000 KHz (3MHz)	Medium Frequency	MF
3 MHz - 30 MHz	High Frequency	HF
30 MHz - 300 MHz	Very High Frequency	VHF
300MHz – 3000MHz (3GHz)	Ultra High Frequency	UHF
3 GHz – 30 GHz	Super High Frequency	SHF
30 GHZ – 300 GHz	Extremely High Frequency	EHF

When it comes to Radio or higher frequencies, the wave length is highly reduced, increasing the frequency proportionally. Velocity is the sum of frequency multiplied with wavelength. You might have noticed that in Radios both wave length and frequency are marked. The velocity of a 500 meters (600 Khz) MW signal is 500 X 600,000 = 300,000,000 (constant). Where ever we have only one of it (frequency or wavelength), divide it with what we have and find the missing factor. 

C-1/2B           Frequency Range	Band
0.39 GHz – to 1.55 GHz	L Band
1.55 GHz to 5.20 GHz	S band
3.70 GHz to 6.20 GHz	C Band
5.20 GHz to 10.9 GHz	X Band
12 GHz to 18 GHz	Ku Band
18 GHz to 27 GHz	K Band
27 GHz to 40 GHz	Ka Band
40 GHz to 300 GHz	m.m Band

That Radio Frequency classification of Long Wave, Medium Wave and Short Wave has now grown into Bands (see chart C-1/2B). The bandwise categorization begins from Gija Hertz range. A thorough study on radio signals is always necessary to understand properly, why different different frequencies are necessary to serve distinct functions. 

The Ionosphere

If all types of radio signals are transmitted rom a particular tower at a time, what that fills most of the global space would be Short Waves. The Ionosphere that surrounds the globe like a shield belt is one among the main factors that decide radio propagation. Ionosphere is the result of millions of radiations in multitudes of frequencies ranging from VHF to Very Ultra High Rays that touch the global space. These radiations from known and unknown stars result in the formation of layers of ionised molecules at a distance of 40-400 kms from earth. For research and observation sake, depending upon its characteristics, ionosphere is divided into four layers - D, F, F1, F2. 

Putting the truth in another words, all radio signals move under the mercy of the ionosphere. All signals in VLF (Very Low Frequency), LF (Low Frequency) and MF (Medium Frequency) ranges are fully absorbed by both ionosphere and the earth. Because of this, only signals that move parallel to earth are useful in those ranges. When it come to Short Waves, both the surface of the earth and the ionosphere act like reflecting mirrors. Shortwave signals move reflected between earth and the Ionosphere, until it gets exhausted. At the same time, Ionosphere bypasses all VHF and UHF signals just like light through a plain glass

While Shortwave signals that are reflected from the ionosphere undergo ‘Fading’, 'Frequency Shift’ and ’Noise Interference’, Medium and Long Waves remain practically undisturbed, without any changes in quality. It doesn’t mean that they are not subject to those changes in the earth’s closest atmospheric layers. The nature of Ionosphere is never static - it keeps changing every time. Truly, the quality of Shortwave transmission depends upon the depth and density of Ionospheric layers. Event though the D layer, which is the closest to earth, is seen only now and then, it causes fading of Short Wave signals. Sunspot which appears on the Sun face on a regular pace causes to ionise the D layer heavily and leading to absolute ‘Black Out’s, a rare situation of no radio signal movement on some frequency spectrums on the earth’s surface. 

Even though the E layer that is just above the D also influences Short Wave remarkably, it is the F class layers that actually reflects them back to earth. During night time the F1 layer comes down to merge with the F layer and as a result Short Wave signals vary in skip distance between day and night. This means that a signal heard during day time at a certain spot need not necessarily be available during night. A Short Wave signal that reaches a particular point during day time most naturally falls somewhere else during night time. This is the reason why we hear new stations at night time. This is not applicable to signals that reach a radio straight from the tower. Point B which is the nearest point to receive a reflected signal and point A which is the longest point to receive a direct Short Wave signal could be away by many kilometres. This area is called the ‘Skip area’. That particular Short wave signals won’t be available there.

The time bound rhythmic working pattern of the Solar System influences Short Wave transmission greatly. There is an 11 years cycle in the solar System which is based on the Sunspot activity, which changes the propagation condition drastically. Major earthly changes like earthquakes also influence ionosphere because of the property changes in the geomagnetic field that results. In similar cases Radio signals are found to be shifting its frequency even upto 70%, while the frequency shift caused by the ionosphere is upto 20% at normal conditions.

It was told early that at VHF and UHF ranges since ionosphere behaves like a conducting medium, what we can utilise are only Direct Waves. That is one reason why we use VHF and Higher frequencies to communicate with artificial satellites in the space. This is the reason why the covering ranges of VHF equipments (used by Hams) and TV transmissions remain low. These all are basic information which we require to proceed further into Hamology.

Introduction                                 Chapter 2

Chapter 3 - PC Board Etching. Radio Listening and QSL Cards

Electronics is the study of electrical energy in its numerous functional possibilities. Today, electronic gadgets are widely assembled by even small school students. Electronics, has now become the most talked about branch of Science and it is deciding our daily lives through numerous thrilling possibilities. 

It is an SWL that becomes a Ham. Most of the operational ethics are learnt through patient listening only. Listening also  helps a  SWL to know who is who. In the last chapter, we discussed about modulation and the necessity of Oscillators in listening. For proper listening of all Ham transmissions we need at least a BFO. BFOs are not available for purchase. This we have to make for ourselves. It is important that one knows how to make a PC board for himself/herself. Bread Boards with holes and prints in definite patterns worked with more jumpers than components have its own draw backs. To be frank, minimum knowledge of the components, soldering expertise and a multimeter aside are not enough to work in a shack. 

Simple circuits are done on leg strips mounted on hard boards or assembled on multi purpose breadboards. But making own Printed Circuit (PC) board is not as difficult as many assume it to be. If a print layout is prepared it can be screen printed on the epoxy board and PC boards of commercial finish are possible. Before we proceed discussing many practical circuits let us learn the nuances of making a PC Board for ourselves. 

The very first thing to do is drawing neatly, the circuit you propose to give life to. Further, decide the size of the board necessary to mount all the components. It is better to collect the components in advance. This will help us to know the size of the space each component requires on the board. Also we need to confirm lead peculiarities of the components and the mode of mounting the components - sleeping or standing. See fig's C-0/1A and C-0/1B 

Now take a graph paper at the actual size of the P C Board. Components should be mounted in a way that the leads do not touch each other. The second stage is preparing the layout. The size of the print is decided mostly depending upon the current the print line handles. In high frequency circuits distance between prints also are important. 

 

Now, make holes on the graph paper so that the leads come out at the graph side of the paper and mark the points. Assuming that the graph side is the print side in the PC Board, connect the leads with lines respectively as seen in the diagram. Lines should be straight and without bends and each should have enough space in between. In case crossing is required (unavoidable) draw the lines with a plan to connect the lines with a jumper wire at the mounting side of the Board. Next we we will take the copper clad board at the necessary size. Copper clad boards are available in different qualities. Most common are paper epoxy and glass epoxy both in single side and double side foils.  If for most of the circuits, ordinary copper clad is enough in high frequency circuits, quality glass epoxy boards are needed. These boards are cut like glass breaking after putting groves on it with sharp knives on either sides. Hacksaw blade also can be used.

Before printing the lines on it the board should be cleaned using some thinner liquids. There shall strictly be no scratches at all. If the board is cleaned hold the paper on the foil side of the board so that we can see the graph side. Mark the hole points on the graph upon the Copper clad board. with a sharp pointed metal rod. Further, remove the paper and draw lines on the copper foil side using some paint. It s not easy to draw these lines using a brush; instead, use a discarded ball pen refill. Take it, remove the metal ball fittings and push out the ball at its tip using a pin. Again fix the metal fitting back to the refill plastic tube. Now you can suck into the tube the paint you propose to use. If the tube s filled with enough paint, start drawing lines as you do it with a regular ball pen. 

Screen printing technology can be used for printed boards with a commercial look.   

How to draw a circuit for etching

During etching we preserve the parts covered with paint while letting all open copper areas dissolve in the solution. The required solution is a chemical called Ferric chloride (FeCl₃₎. It is a very damaging chemical, which should be used very carefully. They are used in School/ College chemistry labs and is available from laboratory materials store in glass bottles. A bottle of ferric chloride is enough for a number of boards. Whatever that touches this powder slowly burns off, be it metal, cloth or wood. This powder is mixed with water only in porcelain or glass bowls. The bowl size should be big enough to hold the board the copper side gets fully sunk in the solution.  Within an hour depending upon the intensity of the solution, the open copper will be etched away. Care should be taken not to touch the solution at any stage. The board is dipped in the solution after the paint on the board is dried. If the solution is heated lightly the etching speed will be increased. In case the solution turns green, it means that the concentration is not enough and more ferric chloride powder is  needed in the solution. Vinegar also can be used in the solution to speed up etching. After all open copper foil is etched out take the board out of the solution and clean it in running water for a while. 
If you find copper sulphate anywhere on the print side of the PC board, it should be cleaned with a dried cloth at press massage. Now the board is ready for having holes on it.  In general cases what we require are 1mm and .8mm drill holes. Bigger holes spoil more lead, while soldering. Before beginning to mount components on it be sure that you have put fixing screw holes also on its' corners. Copper open to atmosphere may get subjected to natural corrosion.  To protect it from similar damages and staining coat it with a paste of rosin crystals (available in hardware stores) diluted in some thinner.  
While fixing the board on the chassis, use plastic beads to keep it a little high.

Chapter 2                                                        Chapter 4 

Chapter 5 - DC Receivers, VFOs

 Why a Direct Conversion Receiver?

In spite of all the inconveniences DC Receivers have, Hams hold it to their hearts. The main reason is not that its' easy to assemble but the fact that the same oscillator used to receive the signal can be used for transmission also without any fine tuning, thus avoiding complicated extra circuits that keep oscillator frequencies always steady. Commercial transceiver manufacturers too do not ignore this favour of easier 'receive - transmit' change over. In fig. C-5/1 the RX/Tx changeover pattern is shown.

Product Detectors

Every time we feed two different frequencies to an active unit, what we get in the out put are 1) fundamental frequencies, 2) a signal at the frequency of difference, 3) a signal at the frequency of added values and 4) a series of harmonics belonging to all these and their images. The best of them is certainly the signal at the added value. But in all the DC and most BC receivers what we utilise are the difference frequency signal. Suppose what we get in the front end of a DC receiver is a 7 MHz signal modulated with a 2.5 KHz audio, according to this theory, if mixed with a 7 MHz signal the difference (modulated intelligence at 2.5 KHz) is made available at the mixer output. Similar mixers are called Product Detectors. 

Simple VFO

Fig C-5/2 is the circuit if a simple VFO (Variable Frequency Oscillator). This VFO is enough to support the DC receiver shown in C-5/3. Note that this DC Receiver VFO circuit has only just one FET (Field Effect Transistor) stage. If we use this stage for transmitter also, an additional buffer stage also is required. It is always better to fix the VFO in a strong body aluminium box (not compulsory while used only for receiving). This circuit is designed for operation at 12 V. Since it should be a regulated voltage, better feed a 15V-18V DC voltage through IC 7812 for a steady 12 V DC.

Receiver Incremental Tuning

At the same time, if what the receiver gets is a CW signal at 7 MHz, since the oscillation frequency and the receiving frequency are the same, no difference is produced. That is, at CW and SSB signals a slight tuning is necessary at the VFO. It is RIT (Receiver Incremental Tuning) circuits that make corresponding frequency changes during transmission and receiving.

Direct Conversion Receiver Circuits 

C-5/3 is the circuit of a very simple DC Receiver. To avoid interferences of out of band signals, DC receivers follow two rules. The first is using tuned antennas and the next is usage of bandpass filers that match with the low gain antenna impedance. Replacing T1, L1 and T2 here will enable the circuit to work at other frequencies too. Even though T1, L1 and T2 are advised to be assembled using ordinary 1 cm IFTs rewound, T 12 (HF-A) toroid, 1 cm IFT type Amidon Iron Powder formers and Philips Shortwave antenna coil formers (IFT Type plastic can) will give you better results in sensitivity and selectivity. 

Q1 here functions like feedback broadband amplifier (just to bring all signals more or less same in strength). Q2 is for mixing and detection. Q3 and IC 1 are audio amplifiers. 

While tuning the front end coils T1, L1 and T2 choose a position as away as possible from BC stations. Before switching on the full unit confirm if VFO Oscillation is in Ham band itself. Without switching off power supply (better to remove the cord from the socket) soldering IC s may result in damaging Q2 and IC-1. 

In C-5/4 a little more improved version of a DC Rx is given. General instructions with regard to front end coils are applicable here too. In this circuit a dual gate MOSFET is used for mixing and detection. The audio received in the output is let through a processing circuit. The first portion of this IC functions as lowpass filter. A clipper circuit which controls heavy power differences between incoming signals also is attached in this portion of the IC.  Since the second portion of the MOSFET works as an audio preamplifier with automatic gain control, low power amplifier ICs like LM 386 is enough in the audio output stage. It will be better if the audio amplifier portion is done on a separate board.

In either case, unless the audio output does not match the speaker impedance, the IC is likely to oscillate in audio frequency. In some DC receivers a separate arrangement to control the strength of the VFO signal also are found. In that case use a 22 PF trimmer in series with the coupling capacitor C-10 connected to the Mixer stage. 

Certainly, the biggest obstacle for an ideal hobbyist is the unavailability of quality components. This ends up in loss of time and energy. Initial failures and hazards scare even determined beginners. Since VFOs are integral parts of Ham Radio Hobbyists, a thorough study of VFOs are inevitable too.

Active and Passive Components 

We know that inductance resistance and capacitance are the three properties of electricity. In a circuit, a component with one of these qualities is called an element. Since none of these has the ability to amplify a given power, they are also called passive components. Since both the leads of these elements do not vary anyway, these components are Bilateral too. Active components like diodes, transistors and valves are different by their capacity to amplify a signal. Unlike passive components, they some times cause change of frequency too.

Be it a passive component or an active component, a RF signal that passes through it might generate multiple signals called harmonics. A harmonic of a frequency is a wave with a frequency that is a positive integer multiple of the frequency of the original wave, known as the fundamental frequency. The rank of a harmonic is set as if the second harmonic of a 7 MHz signal is 14 MHz and third is 21 MHz. In a mixer stage where two frequencies come face to face, the result would not be limited to just a new signal at the frequency of difference. There would be a signal at the added frequency, the fundamentals, the harmonics of everything and thus many signals of varying strength and frequencies. Even though the IF stages reject all these signals except the difference between mixed signals, those signals with frequency close to IF, called Image Frequencies, might pose severe threats. 

Even elements cannot be used in RF stages as literally free as they are in dc circuits. See pic: C-4/1A to see the change when a capacitor is used in RF circuit. The behaviour of an inductor in an RF circuit will be like that in pic: C-4/1B 

Radio Circuits

At ​high ​frequencies, even Composition Carbon (CC) resistors behave like active ​mini circuit packs. We need to consider all these factors every time we think of working on a​ radio circuit. ​While assembling a radio gadget, even if the concerned home brewer observes all the ​available ​instructions exactly as they are meant, ​the result need not be satisfactory.​ ​This is because the components used vary in quality, though same in the given values.​ In a receiver, even passive components fall prey to environmental influences like heat. We are to be careful in fixing heat sensitive components away from heat developing components and corners. ​The frequency, the voltage and the heat ​either applied or developed inside the transistor should always be kept within the specifications of the manufacturer.

​Transistors - ‘ft’ and (β)

Transistors that need different power circuits and power supplies ​at input and out put fall under bipolar components. A bipolar transistor basically consists of three sections called Emitter (E), Base (B) and Collector (C) and the depletion regions inside it fundamentally keeps these sections apart. A depletion region is more or less like the electrolyte in a capacitor. The maximum frequency at which a transistor works might be given in ‘ft’. ​'ft' is defined as the unity gain frequency of a transistor’s short circuit current gain. ​It is always better to have a ‘ft’ of 7-10 times more than the actual frequency range in which a transistor is working. ​

The Beta (β) of a transistor means how much more in times the output current of a transistor is with regard to the input current of the same transistor. The manufacturer records beta in units of ‘hfe’. ‘hfe’ of a transistor is the current gain or amplification factor of a transistor. ​Each transistor will be different in its ‘hfe’ features.​ ‘hfe’ meters are available now. If we keep Emitter and Base in forward bias at a definite voltage, we can measure the collector current and thus compare the ‘hfe’ between transistors. Remember that a transistor is most efficient only when used at a voltage nearer to the specified voltage of that transistor. Even though distortion and instability are sure when bipolar transistors are used in a different voltage spectrum, they can be found to be comfortably working in higher frequencies. 

​Slightly different are Field Effect Transistors (FET). Source (S), where a carrier begins and Drain (D) where a carrier ends are the two important points in a FET. There would be a depletion region close to the carrier channel. It functions exactly like a common gate. A voltage applied at this gate results in the expansion or contraction of the depletion region, which changes the intensity of the carrier current accordingly. This is the working pattern of all FETs. Compared to a bipolar transistor, current development in a FET is faster. The efficiency of FETs to handle comparatively higher current and wider range of frequencies make FETs more acceptable than bipolar transistors. Else reasons for considering FETs in RF circuits are their low noise factor, high stability and high out put impedance factors. 

Chapter 4                                                    Chapter 6