RSS-136 - Land and Mobile Station Radiotelephone Transmitters and Receivers Operating in the 26.960 - 27.410 MHz General Radio Service Band
RSS-136
Issue 5
October 2002
Spectrum Management and Telecommunications Policy
Radio Standards Specification
Table of Contents
- 1.0 Intent
- 2.0 General
- 3.0 Related Document
- 4.0 Equipment Requirements
- 5.0 Standard Test Conditions and Definitions
- 6.0 Receivers
- 7.0 Transmitters
- Land and Mobile Station Radiotelephone Transmitters and Received Operating in the 26.960 - 27.410 MHz General Radio Service Band (PDF, 277 KB, 11 pages)
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1.0 Intent
1.1 This Specification prescribes the minimum standards required for the certification of radiotelephone transmitters and receivers described by the above Specification title.
1.2 Transmitters and receivers certified under this Specification are considered technically suitable for licensing pursuant to the Radiocommunication Regulations made under the Radiocommunication Act. Forty channel allocations have been established in the band 26.960 - 27.410 MHz with the following center frequencies:
All transmitters shall operate with the nominal carrier, fc, at the above frequencies.
2.0 General
2.1 Those seeking approval of equipment under this Specification shall satisfy the Department at their own expense that the equipment actually meets the requirements of this Specification.
2.2 Notwithstanding the fact that a particular piece of equipment meets the requirements of this Specification, the Department reserves the right to require that adjustments be made to that equipment wherever it causes interference within the meaning of the Radiocommunication Act.
2.3 The Department reserves the right to revise this Specification.
2.4 Each allocated channel within the 26.960 - 27.410 MHz band for use by stations in the General Radio Service is available to all licensees of such stations on a shared basis only and will not be assigned for the exclusive use of any one applicant. All participants in this service shall co-operate in the use of the frequencies allocated in order to minimize interference. No protection can be provided against interference.
3.0 Related Document
3.1 Radio Standards Procedure 100 - Radio Equipment Certification Procedure.
4.0 Equipment Requirements
4.1 There shall be no external control which could cause the equipment to operate in a manner violating the requirements of this Specification. If a speech clarifier control is provided it shall not change the transmitter frequency.
4.2 Connection to batteries (if used) shall be made in such a manner as to permit replacement by the user without causing improper operation of the transmitter.
4.3 The equipment generally shall have external connections for a detachable antenna except in the case of portable equipment where this requirement may be relaxed provided the transmitter R.F. circuit is readily accessible for detaching the antenna.
4.4.1 Equipment Identification - The following information shall be permanently displayed on each transmitter, receiver, or inseparable combination thereof evaluated under this specification:
- Manufacturer's name
- Model identification
- Serial number
4.4.2 Certification Identification - Equipment certified by the Department under this specification must, in addition to requirement 4.4.1, permanently display on the same label, the certification number assigned by the Department and the name of the assignee. The certification number and assignee's name must be indelible, tamper-proof, and affixed in such a manner as not to be removable except by destruction or defacing.
4.5 Power Output Limitation - The transmitter shall incorporate circuitry to automatically limit the transmitter RF power output to a level not exceeding 1 db of the power measured in paragraph 7.1.2.
4.6 Permissible Emissions - A3, A3A, A3J
5. Standard Test Conditions and Definitions
5.1 Definition - Standard Test Conditions are those conditions under which the equipment shall be operated while it is being tested for minimum requirements. These conditions shall apply at all times unless otherwise specified.
5.2 Standard Test Voltage - The standard test voltage shall be the primary voltage applied to the input end of the power cable normally connected to the equipment. It shall be within ± 2% of the value stated by the manufacturer to be the normal working voltage.
5.3 Standard temperature - Standard temperature shall be 25°C ± 5°C.
5.4 Standard Output Termination - The standard output termination shall consist of a termination equal to the load into which the transmitter is designed to operate. Its value shall be specified by the manufacturer or applicant and recorded in the test report.
5.5 Standard Input Termination - The standard input termination shall consist of a termination equal to the load into which the receiver is designed to operate. Its value shall be specified by the manufacturer or applicant and recorded in the test report.
5.6 Standard-Test Frequencies - Except where otherwise specified all tests shall be made using at least three RF frequencies in paragraph 1.2: one near the high end, one near the middle and one near the low end of the frequency range for which the equipment is to be certified. The frequencies selected for tests shall be termed the reference or standard test frequencies.
5.7 Assigned Frequency - In the case of DSB equipment the assigned frequency, fa, shall be the standard test frequency, fc. In the case of SSB equipment the assigned frequency, fa, shall be 1.40 kHz above the standard test frequency for USB operation and 1.4 kHz below for LSB operation.
5.8 Two-Frequency Test Signal - The two-frequency test signal shall consist of two sinusoidal tones, the frequencies of which are 850 Hz ± 5% and 1950 Hz ± 5%, which when simultaneously applied to the audio input of an SSB transmitter result in equal amplitude radio frequency output signals.
5.9 Standard Test Set-Up - Internal controls shall be set in accordance with the manufacturer's instructions for normal operation. The transmitter shall be terminated with the standard output termination.
5.10 Frequency Stability Test - The frequency measurements under standard temperature (i.e. paragraph 7.4.2.1) may be the first measurement performed.
6.0 Receivers
6.1 Spurious Output Signals
6.1.1 Definition - Receiver spurious output signals are R.F. signals generated within the receiver which may cause interference to other equipment. This includes the period during which the equipment is scanning or switching channels.
6.1.2 Methods of Measurement - The receiver shall be turned on and spurious outputs shall be measured over the frequency range from the lowest IF frequency to 1000 MHz.
A calibrated test receiver whose input impedance is equal to the receiver's nominal input impedance at the receiver's operating frequency shall be connected to the receiver's antenna terminals. The magnitude of all spurious outputs within the above frequency range shall then be measured.
6.1.3 Minimum Standards - The mean power on any frequency measured at the receiver antenna terminals shall not be greater than 2 nanowatts.
6.2 Receiver Cabinet Radiation
6.2.1 Definition - Any radiation emanating from the cabinet including accessories while equipment is in receive mode. This includes the period during which the equipment is scanning or switching channels.
Note: While the following test is prescribed as the standard, the Department will accept results from 'screen-room' tests provided the testing lab can prove to the satisfaction of the Department that this standard will be met.
6.2.2 Method of Measurement - The antenna input terminal shall be terminated with a dummy load equal to the input impedance of the device. The equipment shall be placed on a non-conducting turntable 1 meter high in an open field. The receiving antenna shall be placed vertically 3 meters from the nearest point on the equipment and the center of the dipole should be 2,5 meters above ground.
The power cables must extend vertically down to the battery or power source near the center of rotation of the table. Excess wire should be coiled near the power source.
The first test for emissions shall be performed with power leads as above and microphone cable extended to its limit vertically above equipment and supported by a non-conducting material.
The second test shall be performed as above except that all additional terminals or jacks shall be provided with a two-conductor unshielded parallel wire or twisted-pair cable 1 meter long.
The additional cables shall also be extended vertically above equipment and supported with a non-conducting material.
During the above tests the turntable shall be rotated through 360° with receiver tuned to the test frequencies in paragraph 5.6.
6.2.3 Minimum Requirements - The field strength measured on any spurious frequency in the range from the lowest IF frequency to 1000 MHz shall not be more than 5 µV/m at 3 meters.
7.0 Transmitters
7.1 R.F. Power Output
7.1.1 Definition - The R.F. power output is the value determined under the following conditions of measurement.
7.1.2 Methods of Measurement
For Single Sideband Emissions - The transmitter shall be modulated with the standard two frequency test signal. A sample of the R.F. output shall be fed to a R.F. spectrum analyzer, or equivalent instrument, and the level of the audio input signal increased until the highest amplitude odd-order difference rf frequency intermodulation product is 20 dB below the level of either of the two test tones or until there is no further increase in output power. The average power output shall then be measured by suitable means. The means used shall be clearly specified in the test report. The peak envelope power is then twice the average power.
For Double Sideband Emissions - The transmitter shall be operated without modulation. The average carrier power output shall then be measured by suitable means. The means used shall be clearly specified in the test report.
7.1.3 Minimum Standard - The carrier power output shall not exceed 4.0 watts for DSB mode of operations. For SSB the R.F. peak envelope power output shall not exceed 12 watts.
7.2 Transmitter Spurious and Harmonic Emissions
7.2.1 Definition - Emission at a frequency or frequencies outside the band necessary to ensure the transmission of information with a given quality. The level of these emissions may be reduced without affecting the quality of the information being transmitted.
7.2.2 Method of Measurement
Single Sideband Transmitters - The transmitter shall be operated into the standard output termination across the antenna terminals with the carrier suppressed and modulated with the two frequency test signal at a level to produce 50% of the average power measured in paragraph 7.1.2. A sample of the rf output shall be fed to a radio frequency spectrum analyzer or equivalent equipment and the level of the input signal increased by 10 dB, with the levels of both fundamental signals equal. The sampled output shall be analyzed from the lowest IF frequency generated to 1000 MHz and levels of all significant components recorded.
If a spectrum analyzer is used a photograph of the spectrum analyzer display under the test conditions specified above shall be submitted with the test data.
Double Sideband Transmitters - The transmitter shall be operated into the standard output terminations across the antenna terminals and modulated with a 2500 Hz sinusoidal signal at a level sufficient to produce 50% modulation.
A sample of the rf output shall be fed to a radio frequency spectrum analyzer or equivalent equipment and the level of the input signal increased by 16 dB. The sampled output shall be analyzed from the lowest IF frequency generated to 1000 MHz and the levels of all significant components recorded.
If a spectrum analyzer is used a photograph of the spectrum analyzer display under the test conditions specified above shall be submitted with the test data.
7.2.3 Minimum Standards
The mean power level of any emission shall not fall within the cross-hatched area of figures 1 and 2.
7.3 Speech Clarifier Test
7.3.1 Method of Measurement - Where a "speech clarifier" control is provided, the following test shall be made. The transmitter shall be operated under standard test conditions. The transmitter output frequency measurements shall be recorded over the full range of the "speech clarifier" control. The lowest frequency measured shall be subtracted from the highest measured. In the case where the suppressed carrier is not measurable, the transmitter may be modulated by an audio tone and the carrier frequency computed from the measured signal.
7.3.2 Minimum Standard - The transmitter frequency shall not vary as the "clarifier" control is varied over its full range.
7.4 Frequency Stability
7.4.1 Definition - The frequency stability is the ability of the transmitter to maintain the standard test frequency under the conditions specified below.
7.4.2 Methods of Measurement - The transmitter shall be adjusted for normal operation under standard test conditions, using a single standard test frequency in paragraph 1.2. No further adjustments shall be made during the following tests unless otherwise specified. The transmitter shall be operated at the rated duty cycle under the conditions specified below. For each temperature condition the equipment temperature shall be allowed to stabilize and the stabilization period shall be stated in the test report. The frequency of the unmodulated carrier shall be measured at least once per minute using a frequency meter having an accuracy of at least 1 ppm. All frequency measurements shall be recorded. In the case of single sideband transmitters when the suppressed carrier is not measurable, the transmitter may be modulated by an audio tone and the suppressed carrier frequency computed from the measured signal frequency.
7.4.2.1 Measurements under Standard Temperature - Turn the equipment on and measure the frequency for twenty minutes. The first measurement should be taken within thirty seconds of turning the transmitter on.
7.4.2.2 Measurements under Temperature and Voltage Extremes
- Low Temperature - Low Voltage - Place the equipment in a chamber at O°C and allow it to stand inoperative (i.e. without primary power supplied) until the temperature has stabilized at O°C. The transmitter shall then have a warm-up period of fifteen minutes under standby conditions. At the end of this period, the transmitter shall be placed in operation in the chamber with the primary voltage decreased to 90% of standard test voltage. Frequency measurements shall then be recorded over a five minute period.
- Low Temperature - High Voltage - This test shall follow immediately after (a) above. The transmitter shall be placed in operation with the primary voltage increased to 110% of standard test voltage. Frequency measurements shall then be recorded over a five minute period.
- High Temperature - Low Voltage - Place the transmitter in a chamber at +40°C and operate it using the appropriate duty cycle until the temperature of the equipment is stabilized. At the end of this period, the primary voltage shall be decreased to 90% of standard test voltage. Frequency measurement shall then be recorded over a five minute period.
- High Temperature - High Voltage - This test shall follow immediately after (c) above. The transmitter shall be placed in operation with the primary voltage increased to 110% of standard test voltage. Frequency measurements shall then be recorded over five minute period.
7.4.3 Minimum Standard - The maximum frequency difference between any of the frequencies measured above and the standard test frequency (paragraph 5.6) shall not exceed 1360 Hz.
Issued under the authority of
the Minister of Communications
John deMercado
Director General
Telecommunication Regulatory Service
