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0. License

Refer to Amateur Handbook from IMDA

Definitions

  • ITC is International Telecommunication Convention
  • ITU is International Telecommunication Union
  • ERP is Effective radiated power
  • PEP is Peak Emission Power
  • Teleprinter / teletypewriter / Teletype / TTY is an electromechanical typewriter that can be used to send and receive typed messages from point to point and point to multipoint over various types of communications channels
  • Telephony is the field of technology involving the development, application, and deployment of telecommunication services for the purpose of electronic transmission of voice, fax, or data, between distant parties.
  • RTTY is Radio Teleprinter
  • CHU is the call sign of a shortwave time signal radio station operated by the Institute for National Measurement Standards of the National Research Council of Canada
  • WWVB is a time signal radio station near Fort Collins, Colorado and is operated by the National Institute of Standards and Technology (NIST)

Exam format

  • Section I Licensing Conditions
    • 35 multiple-choice questions (1 hour)
    • Syllabus:
      • Licensing Conditions
      • Operating Practices and Procedures
      • Transmitter Interference
  • Section II
    • 60 multiple-choice questions (1 hour 45 minutes)
    • Syllabus:
      • Electrical Theory
      • Semiconductors
      • Radio Receivers and Transmitters
      • Propagation and Aerials
      • Measurement

Qualification required of the holder of Amateur Station License

  • Amateur Station Licence for operating radio transmission/reception equipment.
  • pass Radio Amateur's Examination or qualification that is acceptable to IMDA
  • IMDA may refuse without any reason
  • Apply online via Telcom Licensing System
  • Documents required: citizenship, results of the exam / valid cert, station license
  • do not purchase equipment until it is approved

License fee

  • license is renewable every 5 years
  • license fee currently is $100
  • license fee must be paid within 7 days of expiry of the license
    • Late fees will be applicable afterwards.
  • IMDA has waived the frequency application, processing fee and annual frequency usage fee
Important note:
  • Admittedly, as of now, the exam is very old.
  • Also, the current 2016 IMDA Handbook still reflects that the license is renewable annually and fee is $50
  • Please check the IDA Handbook for any updates pertaining to changes in syllabus or regulations.
    • Advised to follow latest IMDA Handbook in regards to this.

Amateur Station License

  • be over 21
  • above 16, the parents / guardian must sign off and be responsible for observation
  • radio amateur equipment is a model that is approved by IMDA

Operation of an Amateur Ratio Station

  • Observer and comply with
    • relevant provisions of the Telecommunications (Radio-communication) Regulations
    • relevant provisions of the Radio Regulations of the ITC
  • amateur station license shall be displayed, in close proximity of the equipment, at the station's licensed address
  • transmitting frequency bands allowed of an amateur radio station shall be at the discretion of IMDA
  • frequency within the limits prescribed by the Radio Regulations, annexed to ITC of the ITU

Transmitting power

  • power of the transmitter shall not exceed 300 watts (DC input)
  • does not cause radio frequency interference to other licensed or authorised stations or networks or telecommunication installation or equipment
  • maximum RF output power allowed for the Restricted Class Station License is 10 watts (erp)

Operational conditions for the Station

  • operated at locations approved by IMDA
  • operated in the presence of the licensee
  • licensee will be responsible for the proper operations of the station
  • tuning of the transmitter must ensure a high degree of accuracy
  • all emissions must be within the authorised bands
  • no appreciable energy is radiated outside the frequency limits
  • a satisfactory method of frequency stabilisation
  • Equipment must be capable of verifying that the emissions are within the authorised bands
  • station shall always be equipped with receiving as well as transmitting equipment
  • all equipment must be erected, fixed, placed and used
  • equipment should not interfere with the efficient and convenient working of other authorised stations
  • must seek approval of any change of equipment, antenna installation, location and address
  • the licensee must identify the transmission of a call sign assigned to him by IMDA at the beginning and end of each period of transmission

Transmission, Procedure & Limitation

  • station may be operated at any time
  • maximum of 10 minutes of continuous transmission
  • messages are
    • allowed
      • sent in plain language
      • relate solely to the licensee's experiments / personal affairs
    • not allowed
      • cannot relate to business affairs or transactions
      • cannot be grossly offensive / indecent / obscene character
  • station cannot send:
    • Government prohibited communication of this nature
    • news
    • advertisement
    • communications of a business or non-experimental character
    • messages for pecuniary / monetary reward
    • messages for or on behalf of a third party
  • Before making any call or test transmission, the frequency on which it is proposed to transmit should be monitored to ensure the transmission will not cause interference to other stations
  • Calling other station
    • call-sign of that stations shall be sent 3 ≤ times ≤ 8
    • signal de for from shall be sent once
    • call-sign of the calling station 3 times
    • call sent 3 times at interval of 2 minutes
    • calling shall cease and may not be resumed until after an interval 15 minutes
  • conversant with the accepted international Q codes
  • call sign must be sent for identification purpose at the beginning and end of each period of transmission
  • prefix for Singapore licensed stations is 9V

Telelphony

  • use international accepted Phonetic Alphabet / figure guide
  • words used in this manner will have a lesser chance of improper interpretation
Phonetic Alphabet
Letter to transmit Word to be used
A Alfa
B Bravo
C Charlie
D Delta
E Echo
F Foxtrot
G Golf
H Hotel
I India
J Juliet
K Kilo
L Lima
M Mike
N November
O Oscar
P Papa
Q Quebec
R Romeo
S Sierra
T Tango
U Uniform
V Victor
W Whisky
X X-ray
Y Yankee
Z Zulu

Station log book

Image credit: 9V1AN's public log

"Grid" column (optional): Maidenhead system for location

  • indelible (of ink or a pen making marks that cannot be removed) record shall be kept in a log-book
  • serially numbered
  • date and time of commencement and ending of every call made from the station
  • call-signs of the stations from which messages addressed to
  • time (local or GMT) of the commencement and termination
  • test transmissions of the station
  • frequency band(s) and class or classes of emission in each case
    • frequency in MHz
    • mode SSB, PSK, etc
    • band in m
  • no gaps shall be left between entries
  • all entries shall be made at the time of sending and receiving
  • the record shall be signed at the time of recording by the licensee
  • log book shall be kept for at least 2 years
  • be available for examination at all reasonable times by an authorised officer of IMDA

Interference

  • Equipment must be designed, constructed, maintained and used in the operation of the station to avoid interference
  • Operator must not cause any harmful interference to other authorised radio services or stations
  • In the case of interference, the licensee shall take all possible steps to eliminate the source of such interference
  • Precautions:
    1. avoid over-modulation
    2. keep the radiated energy within the narrowest possible frequency bands
    3. radiation of harmonics and spurious emissions shall be suppressed
  • tests shall be made from time to time and details of those tests shall be recorded in the station log-book
  • Adjustment of an amateur station shall, in general, be made by using a dummy load

Portable / Mobile station

  • only operate in the frequency bands
  • only be allowed to operate in Singapore
  • mobile / portable station and the general station cannot be operated simultaneously
  • the call-sign = general station followed by /M or /P
  • transmitter output power of the portable station shall not exceed 10 watts (erp)
  • licence may be modified or revoked at any time by IMDA without assigning any reason therefor
  • it is readily movable from place to place to be operated therefrom
  • station fee of $50.00 per mobile/portable station is waived
  • station shall be closed down at any time on the demand of an authorised officer acting under the authority of IMDA

Frequency checking equipment in amateur stations

  • A licensee must:
    • be able to verify that his transmissions are within the authorised frequency band
    • no appreciable energy is radiated outside the band
    • use a satisfactory method of frequency control
    • transmissions do not contain unwanted frequencies
    • transmission do not contain harmonics and spurious frequencies
  • station requires a crystal reference source
    • with a transmitter (crystal-controlled)
      • an absorption device of suitable frequency range and accuracy is necessary
      • check that the desired harmonic of the crystal frequency is selected
    • with a transmitter (not crystal-controlled)
      • a wavemeter based on a crystal oscillator is necessary
  • Frequency measuring equipment
    • should be of sufficient accuracy
      • an accuracy of ±1.0%: operation in the centre of the 21.0 MHz - 21.45 MHz band
      • an accuracy of ±0.05%: 10 kHz of band-edge
    • verify that emissions are within the authorised frequency bands
  • Heterodyne wavemeters and crystal calibrators
    • frequencies up to 4 MHz: 100 kHz crystal is usually adequate
    • higher frequencies: 500 kHz crystal or preferably 1 MHz
  • Absorption wavemeters and similar devices
    • scale length and accuracy should be suitable for measurements of the required accuracy to be made
    • the frequency coverage must extend up to the second and preferably the third harmonic of the radiated frequency
    • For VHF and UHF transmitters
      • best technique is to measure the frequency of the fundamental oscillator as accurately as possible
      • use an absorption device to confirm that the wanted harmonic has been selected
    • VHF or UHF converter
      • the calibration of the main receiver can be checked with sufficient accuracy
      • also advisable to use an absorption wavemeter to check the measurement and to confirm that no unwanted radiations are present

Frequency bands, power and classes of emissions

Conditions Frequency Bands
(in MHz)
Classes of Emission Maximum DC Input Power RF Output PEP
for A1, A2 and A3
- shared by other services
- RTTY may not be used
1.8 - 2.0 A1A, A1B,
A2A, A2B

F1A, F1B, F2A, F2B

A3E, R3E, G3E, H3E, J3E, F3E
10 watts 26.67 watts
- shared by other services 3.5 - 3.9 same as above 300 watts 800 watts
band 10.1 - 10.15
is allocated on secondary basis
7 - 7.10,
10.1 - 10.15,
14 - 14.35,
18.068 - 18.168,
21 - 21.45,
24.890 - 24.990,
28 - 29.7
same as above 300 watts 800 watts
- need consent from IDA
- CW operators use the lower band
- other classes of emission use the mid and upper band
144 – 146 same as above - 25 watts
- need consent from IDA (include power, conditions, operations)
- shared by other services
- only certain spot Frequencies are allocated in Amateur Service -
430 – 440 same as above - Table below
same as above 1240 - 1300,
2300 - 2450,
3300 - 3500,
5650 - 5850,
10000 - 10500
same as above Subject to licensing conditions
same as above 24,000 - 24,050
24,050 - 24,250
same as above Subject to licensing conditions
same as above 2,350 - 2,400, 5,700 - 5,800 K1A, K2A, L2A, K2E and L3E - As above
Band plan and spot frequency
# Band (MHz) Mode Frequencies (MHz) Maximum Output Power
1 432.000 - 432.150 Continuous Wave (CW) only 432.000 10 watts erp
2 432.150 - 432.500 Single-Sideband (SSB) and CW only 432.200 10 watts erp
3 432.500 - 432.800 Radio Teleprinter (RTTY) Facsimile (FAX) 432.600 10 watts erp
4 433.375 - 434.600 FM Simplex Channels 433.625, 433.650 10 watts erp

Modulation symbols

The ITU uses an internationally agreed system for classifying radio frequency signals. Each type of radio emission is classified according to its bandwidth, method of modulation, nature of the modulating signal, and type of information transmitted on the carrier signal. It is based on characteristics of the signal, not on the transmitter used.

Modulation types (1st digit)

Symbol Modulation Carrier Sideband Example
A amplitude Double AM broadcast radio
R reduced or variable Single
G phase
H full Single as used by CHU
F frequency FM broadcast radio
J suppressed Single Shortwave utility and amateur stations
K pulse amplitude
L pulse width used by WWVB

Type of modulating signal (2nd digit)

Number Channel Info Subcarrier Others
0 No modulating signal
1 One digital none without modulating audio frequency
2 One digital using with modulating audio frequency
3 One analog

Type of transmitted information (3rd digit)

Symbol Type Decoded by Example
N No transmitted information
A Aural Telegraphy by ear Morse code
B Electronic Telegraphy (Teletype) radioteletype and digital modes
E Telephony by human voice or music

More Examples:

No. Type Symbol Description
1 Amplitude Modulation A1A Morse telegraphy
2 Amplitude Modulation A1B Teletype telegraphy
3 Amplitude Modulation A2A Morse telegraphy
4 Amplitude Modulation A2B Teletype telegraphy
5 Amplitude Modulation A3E Telephony, double-sideband
6 Amplitude Modulation R3E Telephony, single-sideband, reduced carrier
7 Amplitude Modulation H3E Telephony, single-sideband, full carrier
8 Amplitude Modulation J3E Telephony, single-sideband, suppressed carrier
1 Frequency Modulation F1A Morse telegraphy by frequency-shift keying
2 Frequency Modulation F1B Teletype telegraphy by frequency-shift keying
3 Frequency Modulation F2A Morse telegraphy by on-off keying of frequency-modulating audio frequency
4 Frequency Modulation F2B Teletype telegraphy by on-off keying of frequency-modulating audio frequency
5 Frequency Modulation F3E Telephony by frequency modulation
6 Frequency Modulation G3E Telephony by phase modulation
1 Pulse Modulation K1A Telegraphy by on-off keying of a pulse carrier
2 Pulse Modulation K2A - Telegraphy by on-off keying of a modulating audio frequency or frequencies or by on-off keying of a modulated pulse carrier
- the audio frequency or frequencies modulating the amplitude of the pulses.
3 Pulse Modulation L2A - Telegraphy by on-off keying of a modulating audio frequency or frequencies or by on- off keying of a modulated pulsed carrier
- the audio frequency of frequencies modulating the width (or duration) of the pulses.
4 Pulse Modulation K2E Telephony, amplitude modulated pulses
5 Pulse Modulation L3E Telephony, width (or duration) modulated pulses

International Q Codes

Type Question Answer
1 QRG frequency Will you tell me my exact frequency? Your exact frequency is ____ kHz
2 QRH frequency Does my frequency vary? Your frequency varies
3 QRI frequency What is the tone of my transmission? The tone of your transmission is (a) good, (b) variable, (c) bad
x QRJ x x
5 QRK interference What is the intelligibility of my signals? The intelligibility of your signals is (a) bad, (b) poor, (c) fair, (d) good, (e) excellent
6 QRL interference Are you busy? I am busy. Please do not interfere.
7 QRM interference Is my transmission being interfered with? Your transmission is being interfered with (a) nil, (b) slightly, (c) moderately, (d) severely, (e) extremely
8 QRN interference Are you troubled by static? I am troubled by static (a) nil, (b) slightly, (c) moderately, (d) severely, (e) extremely
9 QRO power Shall I increase transmitter power? Increase transmitter power
10 QRP power Shall I decrease transmitter power? Decrease transmitter power
11 QRQ speed Shall I send faster? Send faster ( ___ words per minute)
12 QRS speed Shall I send slowly? Send more slowly ( ___ words per minute)
13 QRT speed Shall I stop sending? Stop sending
14 QRU call Are you ready? I am ready
16 QRX call When will you call me again? I will call you again at ___ hours on ___ kHz
17 QRZ call Who is calling me? You are being called by ___ on ___ kHz
18 QSA signals What is the strength of my signals? The strength of your signals is (a) scarcely perceptible, (b) weak, (c) fairly good, (d) good, (e) very good
19 QSB signals Are my signals fading? Your signals are fading
20 QSD signals Are my signals mutilated? Your signals are mutilated
21 QSL communicate Can you acknowledge receipt? I am acknowledging receipt
22 QSO communicate Can you communicate with ___ direct? I can communication with ___ direct
23 QSP communicate Will you relay to ___ I will relay to ___
24 QSV communicate Shall I send a series of V's for adjustment on this frequency? Send a series of V's.
25 QSZ communicate Shall I send each word or group more than once? Send each word or group twice
26 QTH location What is your location? My location is ___
27 QTR time What is the correct time? The correct time is ___ hours.