[TenTec] BPL, Harmful Interference

[DJ5IL at aol.com]

> I'd appreciate some help in finding the definition of "harmful 
interference" 
> per 47 C. F. R. paragraph 15.5(b).  I'm working on my letter to the FCC and 
> my congressional representatives.

> Thanks,
>
> Jim, W8KGI

Jim,

I follow the BPL discussion in your country with great interest. In Europe
that dirty technology is called PLC (Power Line Communication) and  here
in Germany we had to face that threat long before it became a topic in the
USA. Unfortunately it seems to be barely known that all radio services are
defined within and ruled by international law. I will take the opportunity to
point out the most important and relevant details. It is quite astonishing 
that the
International Telecommunication Union (ITU) and the Radio Regulations are
not even mentioned on the very detailed PLC information page of the ARRL
(http://www.arrl.org/tis/info/HTML/plc/). Because I consider this to be very
important, a copy of this email goes to Ed Hare, W1RFI (w1rfi at arrl.org). 

The amateur radio service is defined within the International
Telecommunication Convention of the ITU. Currently 189 states, among
them the United States of America and Germany, have signed this Convention
and the 'Radio Regulations' and thus are strictly bound to it.

Here are some important definitions and articles of the Radio Regulations
which are binding law for all ITU member states:

Radio Regulations, Article I, Terms and Definitions:

"1.19 radiocommunication service: A service as defined in this Section
involving the transmission, emission and/or reception of radio waves for
specific telecommunication purposes."

"1.56 amateur service: A radiocommunication service for the purpose
of self-training, intercommunication and technical investigations carried
out by amateurs, that is, by duly authorized persons interested in radio
technique solely with a personal aim and without pecuniary interest."

"1.96 amateur station: A station in the amateur service."

"1.137 radiation: The outward flow of energy from any source in the
form of radio waves."

"1.138 emission: Radiation produced, or the production of radiation,
by a radio transmitting station."

"1.166 interference: The effect of unwanted energy due to one or a
combination of emissions, radiations, or inductions upon reception in a
radiocommunication system, manifested by any performance degradation,
misinterpretation, or loss of information which could be extracted in the
absence of such unwanted energy."

"1.169 harmful interference: Interference which endangers the functioning
of a radionavigation service or of other safety services or seriously
degrades, obstructs, or repeatedly interrupts a radiocommunication
service operating in accordance with these Regulations."

Radio Regulations, Article 15:

"15.12 § 8 Administrations shall take all practicable and necessary
steps to ensure that the operation of electrical apparatus or installations
of any kind, including power and telecommunication distribution
networks ... does not cause harmful interference to a radiocommunication
service and, in particular, to a radionavigation or any other safety service
operating in accordance with the provisions of these Regulations."

Radio Regulations, Article 25:

"25.8 § 5 1) All the general rules of the Convention, the Convention
and of these Regulations shall apply to amateur stations."

Please note thet the definition of "harmful interference" in the Radio
Regulations that are binding law for all ITU member states does not contain
a reference to any EMC emission limits. In fact, harmful interference is not
defined in quantity by exceeding any limits but *in quality* by it's effect on
radio communications. By definition any effect of unwanted energy due to
one or a combination of emissions, radiations, or inductions upon
reception in a radiocommunication system is an interference. If such an
interference seriously degrades, obstructs, or repeatedly interrupts any
radiocommunication service operating in accordance with these
Regulations it is a harmful interference, no matter which standards are
met or not met by the source of interference. In that case, administrations
shall take all practicable and necessary steps to stop that interference.

The essential EMC requirements are that electrical and electronic
appliances shall be so constructed that: the electromagnetic disturbance
it generates does not exceed a level allowing radio and telecommunications
equipment and other apparatus to operate as intended and the apparatus
has an adequate level of intrinsic immunity to electromagnetic disturbance
to enable it to operate as intended. EMC standards define technical
characteristics which can be used to meet these essential requirements.
However, and this is important, if such appliance meets the standards it is
only *presumed* to comply with the essential requirements, nothing more.
This is not just my personal interpretation but a fact that you can find in
many places, for example within the "EMVG" (EMC Act) as part of our
national German law. In the case of EMC emission limits this is logically
the only possible way to go, because otherwise the standards would
infringe the Radio Regulations and thus international law. 

The consequence is: If any electrical or electronic appliance, for example
a PLC-modem, interferes with your reception and your station is in the
amateur radio service, then you definitely have the right to complain and
it does absolutely not matter if the unwanted radiation from that appliance
is within any EMC emission limits. Of course it is highly desireable to have
EMC emission limits as low as possible, but regardless of any standards
amateur radio as well as any other radio service as defined within the
Radio Regulations are protected by international law. That's why it is so
important for us that amateur radio is defined as a radio *service* in
contrast to other radio applications.

Radio amateurs should not hesitate to complain in the case of harmful
interference and show that they know their rights. The more complaints the
authority receives, the higher is the chance that the administration will
favour low emission limits, because they have to fear a disaster when they
are forced to solve thousands of cases of harmful interference.

73
Karl, DJ5IL