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Re: [RFI] The FCC's Class B Standards

To: rfi@contesting.com
Subject: Re: [RFI] The FCC's Class B Standards
From: "Dave Cole (NK7Z)" <dave@nk7z.net>
Date: Tue, 20 Mar 2018 23:54:01 -0700
List-post: <mailto:rfi@contesting.com>
I don't know why, but that bothers me, and it seems like a lessening of the rules, as opposed to what I think should be a tightening of the rules...

73s and thanks,
Dave
NK7Z
https://www.nk7z.net

On 03/20/2018 07:45 PM, David Eckhardt wrote:
Yep.  Correct.  Only in the User's Manual.

On Wed, Mar 21, 2018 at 1:10 AM, Dave Cole (NK7Z) <dave@nk7z.net <mailto:dave@nk7z.net>> wrote:

    Thanks for the info Dave...  I saw, or heard someplace that the FCC
no longer requires a mark on the device, but just in the book... Have you heard anything about this?  I can't remember where I heard it.

    73s and thanks,
    Dave
    NK7Z
    https://www.nk7z.net

    On 03/20/2018 01:25 PM, David Eckhardt wrote:

        Only the FCC logo is REQUIRED to be on the device if it is Class
        B, home
        and small office.  The statement and other regulatory
        information, more
        times than not, is contained in the 'User's Manual'.  Most have a
        regulatory section devoted to this kind of stuff.  If there is
        no FCC logo
        on the product, assume it is either Class A (Industrial) or the
        supplier
        doesn't know much about the regulatory world and required
        markings (no
        attehtion to EMC/RFI).  This is based on some 30 years of doing
        EMC/RFI for
        a living.  What I write is from experience.  When we had a real
        FCC, things
        were very different!!!!

        If it is from China or the PacRim, just assume it has not been
        tested nor
        any attention paid to EMC/RFI.  I have read
        many,.....many,.....bogus
        'reports' on Chinese products, many of which are assembled from
        other
        products and piece mealed from other reports and really don't
        even apply.
        I've also experiencef many, . . . . many, .  . . . .  instances
        of false
        labeling from China.

        Bottom line:  1)  When you shop for something, take a battery
        operated
        radio with you and request a test of the item.
                             2)  It's hard to find otherwise, but don't
        buy if the
        electronics or products are 'Made in China".
                             3)  Don't buy if in the inttruction manual
        or posted on
        the product, "Made of Foreign and Domestic Parts".  That's a
                                  license for Chinese switchers with,
        again, no
        attentioin paid to EMC/RFI.

        However, the biggies like Apple and the like know the game and
        are usually
        to be trusted (except for their wall warts).

        I realize all this reads rather negative, but its reality these
        days!  Just
        believe me ! ! !

        Dave - WØLEV

        On Tue, Mar 20, 2018 at 7:40 PM, Leonard Halvorsen
        <lhalvors@pppl.gov <mailto:lhalvors@pppl.gov>>
        wrote:

            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=
            
<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
            <http://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=
            
<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
            <http://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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--
*Dave - WØLEV
*
*/Just Let Darwin Work/*
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