TELECOMMUNICATION (CORDLESS TELEPHONE APPARATUS) (EXEMPTION FROM LICENSING) ORDER

TELECOMMUNICATION (CORDLESS TELEPHONE APPARATUS) (EXEMPTION FROM LICENSING) ORDER

TELECOMMUNICATION (CORDLESS TELEPHONE

APPARATUS) (EXEMPTION FROM LICENSING) ORDER

(Cap. 106, section 39)

[2 March 1989]

L.N. 317/88

Citation

1. This order may be cited as the Telecommunication (Cordless Tele

phone Apparatus) (Exemption from Licensing) Order.

Interpretation

2. In this order, unless the context otherwise requires

'base unit' means the part of the cordless telephone apparatus connected by

wire to the telephone network;

'cordless telephone apparatus' means any radiocommunication apparatus

designed or adapted to provide a wireless extension to a telephone;

'portable' means the part of the cordless telephone apparatus capable of

connection to the base unit by radio.

Exemption for purposes of section 8(1)(b)

3. A person who is in possession of or uses cordless telephone apparatus

that conforms to the specifications in the Schedule is exempted from section 8(1)(b)
of the Ordinance.

Exemption for purposes of section 8(1)(c) and (d)

4. (1) A person who

(a) deals in the course of trade or business in; or

(b) demonstrates, with a view to sale in the course of trade or business,

cordless telephone apparatus that conforms to the specifications in the Schedule is
exempted from section 8(1)(c) and (d) of the Ordinance on condition that(i) the
apparatus is of a model that the Authority has certified as meeting the specifications
in the Schedule; and

(ii) the base unit and the portable unit of the apparatus each bear a label

identifying the Authority's certification.

(2) The label referred to in subparagraph (1)(ii) shall-
(a) display prominently the words-
'Telecommunication Ordinance (Cap. 106)






Certificate No.


Telecommunications Authority

and the identifying number of the certificate issued by the Authority in
accordance with subparagraph (1)(i);

(b)be rectangular in shape with length and width in the proportions of 2:

(c) be not less than 50 mm long by 25 mm wide;

(d) be light grey in colour behind the words 'Telecommunications
Authority' and white or ivory in colour elsewhere, with the
text in characters of not less than 1.5 nun high; and

(e) be attached to an outside surface of the units.

SCHEDULE [paras. 3 & 4(1)]

PARTI

SPECIFICATION FOR THE RADIO
CHARACTERISTICS OF
CORDLESS TELEPHONE APPARATUS

Interpretation

1. For the purposes of this Part-

'a.c.' means alternating current;

'adjacent channel power' means that part of the total power output of a transmitter under
defined conditions of modulation (that is, modulated by a modulating signal of 1 250 Hz at a
level which is 20 dB greater than that required to produce 60% of the maximum permissible
frequency deviation as allowed under paragraph 9(1)) which falls within the bandwidth of a
receiver of the type normally used in the system and operating in either of the adjacent
channels;

'associated base unit' means the base unit with which a portable unit is intended to operate;

'associated portable unit' means the portable unit with which a base unit is intended to operate;

'cleardown' means the opening of the telephone line loop by the base unit in response to an
appropriate action on the portable unit;

'extreme test conditions' means testing temperatures of between 40 degrees Celsius and 0 degree
Celsius, and testing source voltages equal to

(a)in the case of apparatus to be connected to an arc. mains source, 1. 1 and 0.9 times the
nominal mains voltage where the mains frequency shall be between 49 Hz and 51 Hz; or

(b)in the case of apparatus using the usual type of nickel cadmium battery, 1.25 and 0.85
times the nominal voltage of the battery; or

(c)in the case of apparatus using the Leclanche type battery, 0.85 times the nominal
voltage; or

(d) in the case of apparatus using the mercury type battery, 0.9 times the nominal
voltage;
or

(e)in the case of apparatus using other types of primary batteries, the end point voltage
declared by the equipment manufacturer; or

(f)in the case of apparatus using other power sources or capable of being operated from a
variety of power sources, the extreme test voltages declared by the equipment
manufacturers;





frequency deviation' means the difference between the instantaneous frequency of the
modulated radio frequency signal and the carrier frequency in the absence of modulation;

'incoming call security' means the rejection by the portable unit of ringing commands
transmitted to it from base units other than its associated base unit;

'normal test conditions' means any convenient combination of temperature between 15 degrees
Celsius and 35 degrees Celsius and relative humidity between 10% and 80% and testing
source voltage equal to

(a)in the case of apparatus to be connected to an a.c. mains source, the nominal mains
voltage where the mains frequency shall be between 49 Hz and 51 Hz; or

(b)in the case of apparatus using the usual type of nickel cadmium battery, the nominal
voltage of the battery (1.2 volts per cell); or

(c)in the case of apparatus using other power sources or types of battery, either primary
or secondary, that declared by the equipment manufacturer;

,,outgoing call security' means the rejection by the base unit of line seizure commands and
dialled information transmitted to it by portable units other than its associated portable
unit;

'spurious emission' means emission radiated by the apparatus and its antenna at frequencies
other than those of the carrier and sidebands associated with normal modulation.

Operating frequencies

2. (1) The apparatus shall be capable of transmitting and receiving angle modulated
emissions on not more than 2 of the following pairs of frequencies

Transmitter Frequencies

Channel No. Base UnitPortable Unit
1 1642.00 kHz47.45625 MHz
2 1662.00 kHz47.46875 MHz
3 1682.00 kHz47.48125 MHz
4 1702.00 kHz47.49375 MHz
5 1722.00 kHz47.50625 MHz
6 1742.00 kHz47.51875 MHz
7 1762.00 kHz47.53125 MHz or
47.44375 MHz
8 1782.00 kHz47.54375 MHz

(2) The apparatus shall not contain facilities for transmission of radio frequencies other
than those specified in subparagraph (1).

(3) Where the apparatus is capable of operating on more than one pair of frequencies, the
operating frequencies shall be selected by means of manual switches at the base and portable units

(4) The frequencies for transmission shall not be selectable separately from the frequencies
for reception.

Permitted effective radiated
power

3. (1) The effective radiated power of a portable unit transmitter-

(a)when measured under normal test conditions and without modulation, shall not exceed
10 milliwatts; and

(b)when measured under extreme test conditions and without modulation, shall not be
more than 3 dB above that measured under normal test conditions.

(2) When the effective radiated power of a base unit transmitter is measured under normal
test conditions and without modulation

(a) it shall not exceed 10 milliwatts; and

(b)the maximum direct current power supplied to the output stage of the transmitter shall
not exceed 1 watt.





Security codes for outgoing
calls

4. (1) A portable unit shall be equipped with means for transmitting a coded signal in
connection with any outgoing call ('outgoing call security code') for reception and recognition
by the associated base unit.

(2) A base unit shall be equipped with means for identifying the outgoing call security code.
transmitted from the associated portable unit, and for rejecting all other codes.

(3) The outgoing call security code shall be a member of a set of sequences numbering at
least 10 000 and allocated to the base unit and the portable unit at the time of manufacture.

(4) The means of storage of the outgoing call security code sequence within the unit shall be
such that it is not possible to alter or directly identify (for the purposes of modification) the
code sequence after manufacture without permanently disabling the equipment.

Security codes for incoming
calls

5. (1) A base unit shall be equipped with means for transmitting a coded signal in connection
with any incoming call ('incoming call security code') for reception and recognition by the
associated portable unit.

(2) A portable unit shall be equipped with means for identifying the incoming call security
code transmitted from the associated base unit, and for rejecting all other codes.

(3) The incoming call security code shall be a member of a set of sequences numbering at
least 10000.

(4) The sequence used for the incoming call security code shall be identical to the sequence
used for the outgoing call security code.

(5) The apparatus shall be so designed that the incoming call security code is transmitted to
the associated portable unit whenever a ringing current is applied to the base unit, and the
portable unit generates a burst of audible ringing signal upon receiving the code from the base
unit.

Positive cleardown

6. (1) Where, in the absence of any other signal on the radio channels being used by a
portable unit and its associated base unit, the portable unit is switched from the state in which it
is used for conversation and dialling 'talk' mode') to the state in which it is receptive to
incoming calls standby mode'), or to the 'off' state (if provided), the associated base unit will
respond by reverting to the off line idle state ('cleardown') within one second.

(2) Where a portable unit other than the associated portable unit but using the same carrier
frequencies as the associated portable unit ('the interferer') is within operating range of the base
unit and is in -talk- mode, and

(a)the signal from the interferer, as received at the base unit, is lower in level than the
signal from the associated portable unit by at least 20 dB, 'cleardown' must occur
within one second of the associated portable unit being switched to the standby mode or
off state (if provided); and

(b)the signal from the interferer, as received at the base unit, is higher in level than the
signal from the associated portable unit, cleardown must occur within 30 seconds of the
associated portable unit being switched to the 'standby' mode or 'off' state (if
provided).

Battery low indication

7. (1) A portable unit shall incorporate a 'battery low' indicator for giving visible warning
that the batteries require re-charging.







(2) The indicator shall operate while the user is still able to establish a call and before the
portable unit begins to fail.

Frequency error

8. The difference between the measured carrier frequency of the transmitter and its nominal
value, under both normal test conditions and extreme test conditions, or in the case of the base
unit transmitter with any value of load impedance applied to the transmitter output, shall not
exceed 2.0 kHz.





Frequency deviation

9. (1) Between the normal level of the modulating signal of a transmitter (that is, a level
which produces a frequency deviation of 2.4 kHz for the base unit transmitter or 1.5 kHz for the
portable unit transmitter at a modulation frequency of 1 kHz) and a level 20 dB higher, the
maximum permissible frequency deviation for modulation frequencies of between 300 Hz and 3.4
kHz shall not exceed

(a) for the base unit transmitter, 4.0 kHz; and

(b) for the portable unit transmitter, 2.5 kHz.

(2) At the normal level of the modulating signal of a transmitter, as defined in subparagraph
(1), the frequency deviation

(a)for modulation frequencies of between 3.4 kHz and 7 kHz, shall not exceed the
frequency deviation at a modulation frequency of 3.4 kHz;

(b)for a modulation frequency of 7 kHz, shall not exceed 50% of the maximum
permissible frequency deviation as allowed under subparagraph (1);

(c)for modulation frequencies of above 7 kHz, shall fall at a rate equal to or greater than 3
times per octave.

Adjacent channel
power

10. The adjacent channel power shall not exceed 1 microwatt.

Spurious emission

11. (1) The strength of the electric field of the spurious emission produced by the apparatus
shall not exceed 500 microvolts per metre measured within the frequency range of 0.5 MHz-30
MHz at a distance of 3 metres from the apparatus.

(2) The effective radiated power of the spurious emission produced by the apparatus shall
not exceed 50 nanowatts within the frequency ranges of 87 MHz-137 MHz and 470 MHz-790
MHz, and 250 nanowatts outside these ranges but within the range 30 MHz-1 000 MHz.

PART 11

SPECIFICATION FOR THE PART OF CORDLESS TELEPHONE
APPARATUS FOR
CONNECTION TO THE PUBLIC SWITCHED TELEPHONE NETWORK

Interpretatio
n

12. For the purposes of this Part
means alternating current;

'basic network loop' means the 2 wires, designated W and W, connecting the apparatus to the
telephone exchange;

'break period' means, in loop disconnect signalling, the period during which the current in the
basic network loop falls to the lower of the 2 values used to represent signalling pulses;

'CCITT- means the International Telegraph and Telephone Consultative Committee established
under the International Telecommunication Convention (Buenos Aires 22 December 1952);

'dBm' means the unit for power level such that zero dBm is equal to one milliwatt;

'd.c.' means direct current;

'DTMF' means dual tone multi-frequency;







'idle state' means the condition of the apparatus when it is both offiline and not in the ringing
state;

'inter-digital pause' means the interval between successive pulse trains or tone bursts in a series
of digits;





'loop disconnect signalling' means the form of signalling where the basic network loop is
repeatedly interrupted by signalling pulses during which the current of the loop falls to a
very low value; 'make period' means, in loop disconnect signalling, the period during which
the current in the

basic network loop returns to the higher of the 2 values used to represent signalling pulses;

'network interface' means the point of interconnection between the apparatus and the
subscriber

termination of the public switched telephone network;

'off-line' means the state of the apparatus where the subscriber termination has an electrical con

figuration that enables the current in the basic network loop to be at its minimum steady
state value;

,,on-line' means the state of the apparatus where the subscriber termination has an electrical con

figuration that enables the current in the basic network loop to be at its maximum steady
state value;

'pulse train' means a series of consecutive pulse periods determining a digit signalled to the

telephone network;

'receiving loudness rating' means the receiving loudness rating defined in CCITT Recommenda

tions 1984 Volume V-Series P Recommendations P.64, P.76 and P.79;

'rms' means root mean square;

'sending loudness rating' means the sending loudness rating defined in CCITT Recommendations

1984 Volume V-Series P Recommendations P.64, P.76 and P.79;

',shunt wire' means the wire which connects to the B-wire via a 1.8 microfarads 15% 250 volts

capacitor;

-sidetone masking rating' means the sidetone masking rating defined in CCITT Recommenda

tions 1984 Volume V-Series P Recommendations P.64, P.76 and P.79;

'specification limit graphs' means the graphs numbered CT/001 to CT/008 signed by the Clerk
of

Councils and dated 15 November 1988, copies of which are deposited in the offices of the
Postmaster General at the General Post Office.

Provision of protection
barrier

13. (1) Subject to subparagraph (2), in apparatus using or generating internally a voltage
where the sum of the d.c. component and 3 times the a.c. component of that voltage exceeds
150

volts, one or more protection barriers shall be incorporated at the network
interface.

(2) Nothing in subparagraph (1) shall require the incorporation of a protection barrier in
respect of any ringing signal having a frequency of between 14 Hz and 30 Hz and a voltage

(including any d.c. component) of







(a) less than 100 volts rms with respect to earth; or

(b)less than 150 volts rms and reducing to 100 volts rms or less within 500 milliseconds
when a 2 000 ohm resistor is connected across it.

Proof test voltage for protection barrier
14. (1) Where a protection barrier is required by virtue of paragraph 13-

(a)it shall be capable of withstanding a 50 Hz proof test voltage of (1 500 2E) volts peak
a.c. (where E is the peak a.c. or d.c. voltage to he isolated) or 2 200 volts peak a.c.,
whichever is the greater, for not less than 60 seconds;

(b)the insulation resistance between the 2 points of application of the proof test voltage,
when measured at 500 volts d.c. immediately following this test, shall exceed 20
megaohms; and

(c) it shall-

(i) where d.c. voltage is to be isolated, be of the type referred to in subparagraph (2)
as a capacitor type;

(ii) in any other case be of a type specified in subparagraph (2), and shall comply
with the specifications set down in respect of that type.





(2) For the purposes of subparagraph (1), the types of protection barrier and their
specifications are--

(a) isolating transformer type, where-

(i) the step down ratio of the transformer shall be so designed that the induced
voltage on the isolated winding shall not exceed 50 volts a.c. rms when the maximum
a.c. voltage against which protection is required is applied across the non-isolated
winding; or

(ii) the transformer shall saturate at a flux value such that the induced voltage on the
isolated winding shall not exceed 75 volts a.c. rms;

(b) capacitor type, in which-

(i) where d.c. voltage is to be isolated the capacitor shall be suitable for connection
with either polarity of voltage applied to its terminals; and

(ii) the maximum energy stored by the capacitor shall not exceed 4 joules when it is
fully charged to the maximum voltage against which protection is required;

(c)fuse disconnection barrier, in which, in the case of the voltage against which protection
is required being referenced to earth, fuses or similar devices shall be connected in series
with the A-wire and B-wire, and voltage dependent de-vices shall be connected from the
A-Wire to earth and the B-wire to earth at the network interface point, or, in the case
of the voltage against which protection is required not being referenced to earth, the
fuse or similar device shall be connected in series with either the A-wire or B-wire, and
voltage dependent devices shall be connected across the A-wire and B-wire at the
network interface point, and where in either case

(i) the voltage dependent device shall be of a type that causes a short-circuit between
its terminal in the event of failure;

(ii) when the continuous power rating of the voltage dependent device is exceeded,
the fuse shall operate to isolate the protected circuit before the voltage dependent
device is damaged;

(iii) the current rating of the fuse shall not exceed 250 milliamperes;

(iv) the voltage rating of the fuse shall be not less than the maximum voltage against
which protection is required; and

(v) the fuse shall break and disconnect within 250 milliseconds when a current of 3
times the fuse rated current flows;

(d) isolating relay type, where-

(i) the voltage to be isolated shall be connected to the coil winding of the relay while
the network interface shall be connected to the contact-set of the relay; or

(ii) the voltage to be isolated shall be connected to the contact-set of the relay while
the network interface shall be connected to the coil winding of the relay; or

(iii) the voltage to be isolated and the network interface shall be connected to
separate contact-sets which are isolated from each other by a barrier of insulating
material or a metal screen connected to earth.

Electrical safety standard

15. The apparatus shall comply with the requirements of the British Standard Specification
'Safety requirements for mains-operated electronic and related apparatus for household and
similar general use' (BS415:1979), insofar as that Specification is not varied by this Part.

Independence of line
polarity







16. The requirements specified in the following paragraphs of this Part shall be met
independently of line polarity of the basic network loop.

Insulation resistance at idle
state

17. The insulation resistance of the apparatus shall exceed 5 megaohms when measured with
80 volts d.c. between the 2 terminals of the apparatus designated for connection to the basic
network loop and between either of these wires and earth.

Bleed current at idle
state

18. The apparatus shall not draw more than 30 microamperes when measured with a 50
volts d.c. source via a 1.5 kiloohm resistor,





Capacitance at idle state

19. The apparatus shall not induce a capacitance exceeding 0. 1 microfarad between the B-
wire and the shunt wire.

Voltage level at idle state

20. The apparatus shall not induce a voltage exceeding 2 millivolts peak to peak on the
basic network loop.

Incoming call detection

21. The apparatus shall be so designed that the ringing signal detection circuit is activated by
a ringing signal current of 3 milliamperes rms or greater.

On-line d.c.
characteristics

22. When plotted against the corresponding values of current the steady state voltages
measured at the 2 terminals of the apparatus designated for connection to the basic network loop

shall he not less than zero and not greater than the upper limit of the limit curve determined by
the straight lines joining the successive co-ordinates in the following table and as shown in
specification limit graph No. CT/001



On-line impedance

23. When measured with a d.c. feed current of between 20 milliamperes and 110
milliamperes the impedance of the apparatus presented to the basic network loop shall be such as
to give a balance return loss of greater than 9 decibels

(a) with respect to a 600 ohm resistor, over the frequency range of 300 Hz-3 400 Hz; and

(b)with respect to an impedance reference network consisting of a parallel connection of a
620 ohm resistor and a 3 10 nanofarad capacitor in series with a 370 ohm resistor, over
the frequency range of 200 Hz-4 000 Hz.

Loop disconnect
signalling

24. Apparatus employing loop disconnect signalling shall comply with the following
requirements

(a)for transmitted digits 1 to 9, the basic network loop shall be interrupted and restored for
a number of times that equals the value of the digit sent, and for digit 0, the number of
times shall he 10;

(b)the rate of pulsing shall be not less than 9 pulses per second and not greater than 11
pulses per second;

(c)the break period shall be not less than 63% and not greater than 72% of the total pulse
period;

(d)the inter-digital pause, including one make period, shall be not less than 600
milliseconds and not greater than 920 milliseconds;

(e)the apparatus shall be capable of accepting, storing and transmitting digits also when
interruption occurs to the line-feeding current during the inter-digital pause, where the
interruption

(i) has a duration not greater than 110 milliseconds; and

(ii) starts not less than 90 milliseconds after the last make of the previous digit; and

(iii) finishes not less than 100 milliseconds prior to the first break of the following
digit;





(f)after pulsing out of the last digit held in the store the apparatus shall be capable of
accepting digit signals for a period of 500 milliseconds also when interruption occurs to
the line-feeding current, where the interruption

(i) has a duration not greater than 110 milliseconds; and

(ii) starts not less than 90 milliseconds after the last break pulse; and

(iii) finishes not more than 460 milliseconds after the last break pulse;

(g)during the pulse break period the resistance of the pulsing out loop of the apparatus shall
exceed 100 kiloohms

(h)when connected to a 48 volts d.c. supply through a series resistor of 1850 ohms the
current produced by the pulsing out loop of the apparatus shall exceed 22 milliamperes.

DTMF signalling

25. Apparatus employing DTMF signalling shall comply with the following requirements-

(a)the signal transmitted by the apparatus to the basic network loop to represent each digit
shall consist of 2, and only 2, frequencies, the nominal value of which shall be as in the
following table ('nominal frequencies')-


(b)the difference between each measured frequency and the corresponding nominal
frequency shall be not more than 1.5% of the nominal frequency;

(c)when plotted against the corresponding values of line current the signal power level of
the DTMF signal measured across a 600 ohm resistive load shall be not greater than the
upper limit and not less than the lower limit of the corresponding limit curves
determined by straight lines joining the successive co-ordinates in the following table
and as shown in specification limit graph No. CT/002





(d)the level of the high frequency component of the DTMF signal shall be not less than,
nor more than 4 decibels greater than, the level of the signal's low frequency
component;

(e)the total power of all unwanted frequency components shall be not less than 20 decibels
below the lower limit for the low frequency group of the signal;

(f)the level of any individual unwanted frequency component shall not exceed the limit of
the limit curve determined by the straight lines joining the successive co-ordinates in
the following table and as shown in specification limit graph No. CT/003



(g)the level of each of the frequency components shall reach to within 1 decibel of the
final value within 10 milliseconds from the time when any one button is depressed;

(h)when no button is depressed, or at any time after 10 milliseconds from the time when
any button is released, the total power level of any signal emitted from the apparatus to
the basic network loop shall not exceed 80 dBm;

(i)the inter-digital pause or any DTMF signal shall have a duration of not less than 50
milliseconds;

(j)apparatus employing an automatic DTMF dialler shall comply with the following
timing format

(i) the signal duration and inter-digital pause shall be not less than 50 milliseconds
and not greater than 200 milliseconds;

(ii) the apparatus shall be capable of sending digit signals not earlier than 1 second
and not later than 5 seconds after the telephone exchange line is seized;

(k)the peak voltage of transients generated by the apparatus during dialling or release of
any button shall not exceed 6 volts.

Sending loudness rating

26. When plotted against the corresponding values of cable length the sending loudness
rating of the apparatus shall he not greater than the upper limit and not less than the lower limit
of the limit curves determined by straight lines joining the successive co-ordinates in the
following table and as shown in specification limit graph No. CT/004



Receiving loudness rating

27. When plotted against the corresponding values of cable length the receiving loudness
rating of the apparatus shall be not greater than the upper limit and not less than the lower limit
of the limit curves determined by straight lines joining the successive co-ordinates in the
following table and as shown in specification limit graph No. CT/005-





Sidetone masking rating

28. When plotted against the corresponding values of cable length the sidetone masking
rating of the apparatus shall be not greater than the upper limit and not less than the lower limit
of the limit curves determined by straight lines joining the successive co-ordinates in the
following table and as shown in specification limit graph No. CT/006



Transmission power limitation

29. When plotted against corresponding values of frequency the power level of individual
spectral components of the energy transmitted by the apparatus into the basic network loop
shall not exceed the limit of the limit curve determined by straight lines joining the successive co-
ordinates in the following table and as shown in specification limit graphs No. CT/007 and
CT/008-

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