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   September 3, 2010

   (Name withheld)

   (Address withheld)

   (Address withheld)

   RE:  Radio frequency interference


   Dear Mr. & Mrs. (name withheld):

   The Federal Communications Commission has received a complaint that an
   electrical device, possibly a faulty doorbell transformer, apparently in
   your home may be causing harmful radio interference to an operator in the
   Amateur Radio Service. The complainant is:

   (Name withheld)

   (Address withheld)

   (Address withheld)

   The Commission has the responsibility to require that such problems be
   rectified within a reasonable time if the interference is caused by faulty
   consumer equipment. Under FCC rules, certain types of equipment are
   classified as "incidental radiators." These devices do not intentionally
   generate any radio-frequency energy, but that may create such energy as an
   incidental part of its intended operation. Common examples are faulty
   doorbell transformers, aquarium heaters, fluorescent light ballasts,
   doorbell control circuits and so forth.

   Other types of consumer devices are classified as "unintentional
   radiators." These devices generate radio frequency energy but do not
   intentionally radiate it. Some common examples include computers, radio
   receivers and television sets. Some of these devices are imported and do
   not comply with Commission certification standards, and thereby result in
   interference to other radio services. If the source of the interference is
   an unintentional radiator, you may have one of these devices. If the
   device is an approved one, it should have a silver FCC label on the unit
   showing a certification number. Even an approved device, however, can only
   be operated legally if it is not causing harmful interference to a
   licensed radio service. Both incidental and unintentional radiators can
   also be defective resulting in a shock or fire hazard.

   To help you better understand your responsibilities under FCC rules, here
   are the most important rules relating to radio and television interference
                           from incidental radiators:

          Title 47, CFR Section 15.5 General conditions of operation.

   (b) Operation of an intentional, unintentional, or incidental radiator is
   subject to the conditions that no harmful interference is caused and that
   interference must be accepted that may be caused by the operation of an
   authorized radio station, by another intentional or unintentional
   radiator, by industrial, scientific and medical (ISM) equipment, or by an
   incidental radiator.

   (c) The operator of the radio frequency device shall be required to cease
   operating the device upon notification by a Commission representative that
   the device is causing harmful interference. Operation shall not resume
   until the condition causing the harmful interference has been corrected.

               Title 47, CFR Section 15.13 Incidental radiators.

   Manufacturers of these devices shall employ good engineering practices to
   minimize the risk of harmful interference.

          Title 47, CFR Section 15.15 General technical requirements.

   (c) Parties responsible for equipment compliance should note that the
   limits specified in this part will not prevent harmful interference under
   all circumstances. Since the operators of Part 15 devices are required to
   cease operation should harmful interference occur to authorized users of
   the radio frequency spectrum, the parties responsible for equipment
   compliance are encouraged to employ the minimum field strength necessary
   for communications, to provide greater attenuation of unwanted emissions
   than required by these regulations, and to advise the user as to how to
   resolve harmful interference problems (for example, see Sec. 15.105(b)).

   The complainant has attempted unsuccessfully to resolve this problem and
   as a result the matter has been referred to our office. The Commission
   prefers that those responsible for the proper operation of equipment
   assume their responsibilities fairly. This means that you should resolve
   the interference caused by the device and make necessary corrections
   within a reasonable time.

   While the Commission has confidence that most people are able to resolve
   these issues voluntarily, the Commission wants to make you aware that this
   unresolved problem may be a violation of FCC rules and could result in a
   monetary forfeiture (fine) for each occurrence. At this stage, the FCC
   encourages the parties to resolve this problem without Commission
   intervention; but if necessary to facilitate resolution, the Commission
   may investigate possible rules violations and address appropriate

   Please advise this office and (name withheld) as to what steps you are
   taking to correct this reported interference problem. The Commission
   expects that most cases can be resolved within 30 days of the time they
   are first reported. Please feel free to contact me in writing at: 1270
   Fairfield Road, Gettysburg, PA 17325 or via telephone at 717-338-2577 if
   you have any questions about this matter.


   Laura L. Smith, Esq.

   Special Counsel Enforcement Bureau

   cc: Denver Field Office

   Western Regional Director