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[RFI] The FCC's Class B Standards

To: rfi@contesting.com
Subject: [RFI] The FCC's Class B Standards
From: Leonard Halvorsen <lhalvors@pppl.gov>
Date: Tue, 20 Mar 2018 15:40:46 -0400
List-post: <mailto:rfi@contesting.com>
Has everyone come to the same conclusion...
"*...**IF* you can find them." ???

[RFI] LED Bulb noise Eleta E12

I read a while ago that to avoid, or at least mitigate to great extent,
interference, an RF noise source must meet FCC standards for a "Class B"
device. What I read stated it was defined in Part 17 (it seems to be Part
15 instead; possibly a typo) of the FCC rules, but I found many references
to it in this *official* 120-page pdf document
<https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwjgprG4lLPZAhVHulMKHQF5AQQQFggoMAA&url=https%3A%2F%2Fwww.gpo.gov%2Ffdsys%2Fpkg%2FCFR-2009-title47-vol1%2Fpdf%2FCFR-2009-title47-vol1-part15.pdf&usg=AOvVaw1Op9mrNNvD_YdVp_5mAmKU>.
This passage on page 23 states what manufacturers must put on such devices..

(b) For a Class B digital device or peripheral,
the instructions furnished the
user shall include the following or
similar statement, placed in a prominent
location in the text of the manual:

NOTE: This equipment has been tested and
found to comply with the limits for a Class
B digital device, pursuant to part 15 of the
FCC Rules. These limits are designed to provide
reasonable protection against harmful
interference in a residential installation.
This equipment generates, uses and can radiate
radio frequency energy and, if not installed
and used in accordance with the instructions,
may cause harmful interference
to radio communications. However, there is
no guarantee that interference will not occur
in a particular installation. If this equipment
does cause harmful interference to
radio or television reception, which can be
determined by turning the equipment off and
on, the user is encouraged to try to correct
the interference by one or more of the following
measures:
—Reorient or relocate the receiving antenna.
—Increase the separation between the equipment
and receiver.
—Connect the equipment into an outlet on a
circuit different from that to which the receiver
is connected.
—Consult the dealer or an experienced radio/
TV technician for help.

I tried to locate devices that adhered to this at places like Home Depot
and Lowes, but was unsuccessful.

This 7-page pdf document
<https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwjSsf7jl7PZAhWStlkKHQtWCB0QFggyMAA&url=https%3A%2F%2Fwww.cableorganizer.com%2Fimages%2Fkensington%2Fmicrosaver-alarm-lock%2FFCC-rules.pdf&usg=AOvVaw2kXOZ71VpqTqByfN3bb6HO>
  attempts to abbreviate and interpret the legalese above. In it is this
passage on page two...

Two levels of radiation and conducted emissions limits for unintentional
radiators are specified in FCC Part 15 Subpart B.

The two levels are Class A digital devices, the higher less strict limits,
and Class B digital devices, the lower more strict limits.

Manufacturers are encouraged to meet the Class B digital device limits.



So, *the key* seems to be to find devices that meet "Class B" standards ...
*IF* you can find them.
If they are made  someplace in the Far East, that is probably impossible.
Compliance costs are probably too high, and most people probably don't care.
And if you can find them, they are probably expensive.
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