In keeping with the international audience, the actual legal rules around power levels allowed for unlicensed FM broadcasting vary from country to country. I am attempting to find regulations for each of the Major countries an if people can point me to a web page or PDF i will edit this post and update.
This post is to provide you with the actual regulations governing the use of FM transmitters for un-licensed broadcasting. Please advise of any changes, amendments or out right mistakes with links to the original regulations.
First off USA...
Title 47--Telecommunication
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CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION
PART 15--RADIO FREQUENCY DEVICES
15.239 Operation in the band 88–108 MHz.
(a) Emissions from the intentional radiator shall be confined within a band 200 kHz wide centered on the operating frequency. The 200 kHz band shall lie wholly within the frequency range of 88–108 MHz.
(b) The field strength of any emissions within the permitted 200 kHz band shall not exceed 250 microvolts/meter at 3 meters. The emission limit in this paragraph is based on measurement instrumentation employing an average detector. The provisions in § 15.35 for limiting peak emissions apply.
(c) The field strength of any emissions radiated on any frequency outside of the specified 200 kHz band shall not exceed the general radiated emission limits in § 15.209.
what's the above mean.. here's a simple read, http://www.gate.net/~advradio/fcc.html
Australia...
From
Radiocommunications (Low Interference Potential Devices) Class Licence 2000
Class Licence
(1) This Class Licence authorises a person to operate a transmitter included in a class of transmitters mentioned in item in Schedule 1, subject to the following conditions:
(a) the transmitter must be operated:
(i) on a frequency, or within a range of frequencies, mentioned in
the item; and
(ii) at a radiated power that does not exceed the maximum EIRP
mentioned in the item; and
(iii) within the limitations (if any) mentioned in the item;
(b) the transmitter’s operation must not cause interference to the operation
of radiocommunications services.
-----------
Schedule 1 Transmitters
Item 21: Wireless audio transmitters and auditory assistance transmitters
Freq: 88-108 Mhz
Max EIRP: 10uW
Limitations
1. Emission must be frequency modulated and have a maximum bandwidth of 180 kHz.
2. Transmission in a radio channel must not originate in the licence area of a radio broadcasting station (including a repeater or translator station) operating in the same channel.
-----------------------------------------------
See the wikipedia for EIRP http://en.wikipedia.org/wiki/Equivalent_isotropically_radiated_power
-----------------------------------------------
Others, please let me know
Phil
This post is to provide you with the actual regulations governing the use of FM transmitters for un-licensed broadcasting. Please advise of any changes, amendments or out right mistakes with links to the original regulations.
First off USA...
Title 47--Telecommunication
--------------------------------------------------------------------------------
CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION
PART 15--RADIO FREQUENCY DEVICES
15.239 Operation in the band 88–108 MHz.
(a) Emissions from the intentional radiator shall be confined within a band 200 kHz wide centered on the operating frequency. The 200 kHz band shall lie wholly within the frequency range of 88–108 MHz.
(b) The field strength of any emissions within the permitted 200 kHz band shall not exceed 250 microvolts/meter at 3 meters. The emission limit in this paragraph is based on measurement instrumentation employing an average detector. The provisions in § 15.35 for limiting peak emissions apply.
(c) The field strength of any emissions radiated on any frequency outside of the specified 200 kHz band shall not exceed the general radiated emission limits in § 15.209.
what's the above mean.. here's a simple read, http://www.gate.net/~advradio/fcc.html
Australia...
From
Radiocommunications (Low Interference Potential Devices) Class Licence 2000
Class Licence
(1) This Class Licence authorises a person to operate a transmitter included in a class of transmitters mentioned in item in Schedule 1, subject to the following conditions:
(a) the transmitter must be operated:
(i) on a frequency, or within a range of frequencies, mentioned in
the item; and
(ii) at a radiated power that does not exceed the maximum EIRP
mentioned in the item; and
(iii) within the limitations (if any) mentioned in the item;
(b) the transmitter’s operation must not cause interference to the operation
of radiocommunications services.
-----------
Schedule 1 Transmitters
Item 21: Wireless audio transmitters and auditory assistance transmitters
Freq: 88-108 Mhz
Max EIRP: 10uW
Limitations
1. Emission must be frequency modulated and have a maximum bandwidth of 180 kHz.
2. Transmission in a radio channel must not originate in the licence area of a radio broadcasting station (including a repeater or translator station) operating in the same channel.
-----------------------------------------------
See the wikipedia for EIRP http://en.wikipedia.org/wiki/Equivalent_isotropically_radiated_power
-----------------------------------------------
Others, please let me know
Phil