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.