Wireless Communication: Amateur Radio

 WHAT IS WIRELESS COMMUNICATION? 

Wireless communications is the transmission of voice and data without cable or wires. In place of a physical connection, data travels through electromagnetic signals broadcast from sending facilities to intermediate and end-user devices.

The groundwork for modern wireless networking was laid in the early 1970s with the launch of ALOHAnet in Hawaii. The network, technically a wide area network (WAN), relied on ultra-high frequency signals to broadcast data among the islands. The technology underpinning ALOHAnet helped fuel the creation of Ethernet in 1973 and played an important role in the development of 802.11, the first wireless standard.

HISTORY IN INDIA:

 

The first amateur radio operator in India was Amarendra Chandra Gooptu (callsign 2JK), licensed in 1921.^[5][6] Later that year, Mukul Bose (2HQ) became the second ham operator, thereby introducing the first two-way ham radio communication in the country.^[5] By 1923, there were twenty British hams operating in India. In 1929, the call sign prefix VU came into effect in India,^{[citation needed]} replacing three-letter call signs. The first short-wave entertainment and public broadcasting station, "VU6AH", was set up in 1935 by E P Metcalfe, vice-chancellor of Mysore University.^[5][6] However, there were fewer than fifty licence holders in the mid-1930s, most of them British officers in the Indian army.^{[citation needed]}

With the outbreak of World War II in 1939, the British cancelled the issue of new licences.^[7] All amateur radio operators were sent written orders to surrender their transmitting equipment to the police, both for possible use in the war effort and to prevent the clandestine use of the stations by Axis collaborators and spies. With the gaining momentum of the Indian independence movement, ham operator Nariman Abarbad Printer (VU2FU) set up the Azad Hind Radio to broadcast Gandhian protest music and uncensored news; he was immediately arrested and his equipment seized. In August 1942, after Mahatma Gandhi launched the Quit India Movement, the British began clamping down on the activities of Indian independence activists and censoring the media. To circumvent media restrictions, Indian National Congress activists, led by Usha Mehta, contacted Mumbai-based amateur radio operators, "Bob" Tanna (VU2LK) and Nariman Printer to help broadcast messages to grass-roots party workers across the country.^{[citation needed]} The radio service was called the "Congress Radio", and began broadcasting from 2 September 1942 on 7.12 MHz. The station could be received as far as Japanese-occupied Myanmar. By November 1942, Tanna was betrayed by an unknown radio officer and was forced to shut down the station.^[7]

Temporary amateur radio licences were issued from 1946, after the end of World War II. By 1948, there were 50 amateur radio operators in India, although only a dozen were active.^[5] Following India's independence in 1947, the first amateur radio organization, the Amateur Radio Club of India was inaugurated on 15 May 1948 at the School of Signals at Mhow in Madhya Pradesh.^[5] The club headquarters was later moved to New Delhi, where it was renamed the Amateur Radio Society of India (ARSI) on 15 May 1954.^[5] As India's oldest amateur radio organization,^{[citation needed]} ARSI became its representative at the International Amateur Radio Union.^[8]

AMATEUR RADIO: Introduction

Ham radio is a licensed radio service that enables you to communicate all around the world and even outer space with your own equipment. It’s vital for emergency communications, technological advancement, and it’s an incredible hobby with over 750,000 licensed hams in the United States.

Founding:

The nickname “ham radio” goes all the way back to the 1890s.

At that time, radio communication wasn’t invented yet – telegraph operators still sent morse code over cables that used physical wires.

But that all changed in 1894 when the world’s first amateur radio operator, inventor Guglielmo Marconi, created the first successful wireless radio contact with his homemade antenna and station.

Ham radio operators can use up to 1,500 watts of power on some frequency bands.
By comparison, the walkie talkie radios you can use without a license operate on FRS, which has a maximum of only 2 watts, making ham radio 750 times more powerful.
Ham radio is 375 times more powerful than CB radio, which was made popular by truckers. CB is capped at just 4 watts. Finally, hams can use 30 times more power than the licensed operators using the GMRS service.

    The Level 1 Technician License is great for local communications and limited long range.

        The Level 2 General License opens up HF frequencies for long range and international contacts.

The Level 3 Amateur Extra License is the most powerful non-commercial radio license available in the United States, and includes many benefits like frequency and mode access, special call signs, international reciprocity, and more.

USE OF 'HAM' RADIOS:

Hams around the world leverage their frequency privileges in many different ways, but the three main areas are Emergency and Off-Grid Communications, Technological Advancement, and Hobby & Contesting.

Other purposes include emergency contacting, where all you need is an antenna and a little information on how to operate the amateur (or ham) radio and contact with people throughout the world.

EXAMINATION:

Amateur Station Operator's Certificate or ASOC is the examination that needs to be passed to receive an amateur radio licence in India.^[17] The exam is conducted by the Wireless and Planning and Coordination Wing (WPC), which comes under the Department of Telecommunications of the Ministry of Communications.^[18] The examination is held monthly in Delhi, Mumbai, Kolkata and Chennai, every two months in Ahmedabad, Nagpur and Hyderabad, and every four months in some smaller cities.^[19] The licence may be awarded to an individual or a club station operated by a group of licensed amateur radio operators.

The written test for the Restricted Grade consists of 50 questions related to radio theory and practice and radio regulations (25 questions in each section), that one must attempt in one hour. The written test for the General Grade consists of 100 questions, with 50 questions in each section, that have to be attempted in two hours. A candidate must score a minimum of 40% (50% for General grade) in each written section, and 50% (60% for the General grade) in aggregate for passing the test.^[15]
The application and licensing procedures are done online through the SaralSanchar portal, short for Simplified Application For Registration And Licenses, which is a web portal for license management under the Department of Telecommunications.

RADIO PRACTICES:

The first subtopic is the elementary theory of electricity that covers topics on conductors, resistors, Ohm's law, power, energy, electromagnets, inductance, capacitance, types of capacitors and inductors, series and parallel connections for radio circuits. The second topic is the elementary theory of alternating currents. Portions include sinusoidal alternating quantities such as peak values, instantaneous values, RMS average values, phase; electrical resonance, and quality factor for radio circuits. The syllabus then moves on to semiconductors, specifically the construction and operation of valves, also known as vacuum tubes. Included in this portion of the syllabus are thermionic emissions with their characteristic curves, diodes, triodes and multi-electrode valves; and the use of valves as rectifiers, oscillators, amplifiers, detectors and frequency changers, stabilisation and smoothing.

Radio receivers is the fourth topic that covers the principles and operation of TRF receivers and Superheterodyne receivers, CW reception; with receiver characteristics such as sensitivity, selectivity and fidelity; Adjacent-channel interference and image interference; AGC and squelch; and signal-to-noise ratio (S/R). Similarly, the next topic on transmitters covers the principles and operation of low power transmitters; oscillators such as the Colpitts oscillator, Hartley oscillator, crystal oscillators, and stability of oscillators.

The last three topics deal with radio propagation, aerials, and frequency measurement. Covered are topic such as wavelength, frequency, nature and propagation of radio waves; ground and sky waves; skip distance; and fading. Common types of transmitting and receiving aerials such as Yagi antennas, and radiation patterns, measurement of frequency and use of simple frequency meters conclude the topic.

Radio Regulations[edit]

Knowledge of the Indian Wireless Telegraph Rules and the Indian Wireless Telegraphs (Amateur Service) Rules are essential and always tested.The syllabus also includes international radio regulations related to the operation of amateur stations with emphasis on provisions of radio regulation nomenclature of the frequency and wavelength, frequency allocation to amateur radio service, measures to prevent harmful interference, standard frequency and time signals services across the world, identification of stations, distress and urgency transmissions, amateur stations, phonetic alphabets, and figure code are the other topics included in the portion.

Also included in the syllabus are Q codes such as QRA, QRG, QRH, QRI, QRK, QRL, QRM, QRN, QRQ, QRS, QRT, QRU, QRV, QRW, QRX, QRZ, QSA, QSB, QSL, QSO, QSU, QSV, QSW, QSX, QSY, QSZ, QTC, QTH, QTR, and QUM; and abbreviations such as AA, AB, AR, AS, C, CFM, CL, CQ, DE, K, NIL, OK, R, TU, VA, WA, and WB.

Morse Code Test[edit]

Candidates who appear for the General grade licence examination must also take and pass the Morse receiving and sending test simultaneously. There is no Morse test for the Restricted grade. The test piece consists of a plain language passage of 200 letters which may consist of letters, figures and punctuation marks such as the full stop, comma, semicolon, break sign, hyphen and question mark.

Receiving
Candidates have to receive for five consecutive minutes at a speed of 8 words per minute, the test piece from an audio oscillator keyed either manually or automatically. Accurately receiving a part of the test piece for one consecutive minute is required to pass the receiving test. A short practice piece is sent at the prescribed speed before the start of the test. Making more than five errors disqualifies a candidate. The average words consist of five characters and each figure and punctuation is counted as two characters.

Sending
The test piece is similar to the one provided in the receiving section. Candidates are required to transmit by using a straight Morse key for five consecutive minutes at the minimum speed of 8 words per minute. A short practice piece is allowed before the test. Candidates are not allowed more than one attempt in the test. Making more than five errors disqualifies a candidate.