I should add something here.
The LED bulbs that insert into Edison sockets are the easiest to tame
because the only source of RFI is the AC line. They're otherwise too small
to be effective radiators. But the 4' shop lights feature a long physical
string of usually electrically series connected LEDs that are fed with a
common constant current via a built-in SMPS. The SMPS does not have to
drive the LED's with low ripple current in order for the LED's to deliver
good illumination to the eye. A manufacturer can save money on L's and C's
by allowing the driving current waveform to be rather ugly, resulting in
direct radiation from the fixture itself. I verified this behavior with
the FEIT work lights in my garage.
Dennis AE6C
On Fri, Dec 20, 2019 at 1:45 PM Dennis Monticelli <
dennis.monticelli@gmail.com> wrote:
> The FEIT shop light fixture came with a 4' two-wire cord and the extension
> was also two wire. I did a quick experiment with a ferrite choke about a
> year ago and it helped, but much more choking was obviously needed to shut
> down the BCB problem.
>
> FYI. We have a bad HF noise problem at the California Historical Radio
> Society that stems from numerous high-mounted LED fixtures (not FEIT) in
> which there is a third wire from fixture all the way to the sub-panel. The
> problem with third wires is that by the time they thread their way through
> the building and find earth ground, they do not represent an RF ground.
>
> Dennis AE6C
>
> On Fri, Dec 20, 2019 at 1:25 PM Dale Johnson <dj2001x@comcast.net> wrote:
>
>> Does the nine ft extention cable have a third connection, saftey ground
>> to the box? Some extensions do not just two wires.
>>
>> Dale j
>>
>>
>>
>> On 20, Dec 2019, at 13:48, Dennis Monticelli <dennis.monticelli@gmail.com>
>> wrote:
>>
>> Doug,
>>
>> Good question. It was and remains an individual outlet connected via a 9'
>> extension cord. The latter may have increased the radiation.
>>
>> Dennis AE6C
>>
>> On Fri, Dec 20, 2019 at 10:53 AM Dale Johnson <dj2001x@comcast.net>
>> wrote:
>>
>> > Did you chain them, plug one into the next or did you plug each fixture
>> > into an outlet?
>> >
>> > I found chaining them creates noise, individual outlets doesn’t.
>> >
>> > Dale k9vuj
>> >
>> >
>> >
>> >
>> > On 20, Dec 2019, at 11:48, Dennis Monticelli <
>> dennis.monticelli@gmail.com>
>> > wrote:
>> >
>> > I bought some FEIT 4' shop lights for the garage. They work well but
>> are
>> > noisy in BCB and lower HF. My antennas are right above the roof.
>> Because
>> > I turn off the shop lights when I'm not in the garage they don't
>> present a
>> > problem with hamming or the kitchen AM radio that is at the opposite
>> end of
>> > the house. Otherwise, I would have to do something about it such as
>> > explore filters.
>> >
>> > While some brands seem better than others, in general I have found that
>> you
>> > can't simply count on a brand. You have to buy the lamp and test it.
>> >
>> > Dennis AE6C
>> >
>> > On Fri, Dec 20, 2019 at 9:00 AM <rfi-request@contesting.com> wrote:
>> >
>> >> Send RFI mailing list submissions to
>> >> rfi@contesting.com
>> >>
>> >> To subscribe or unsubscribe via the World Wide Web, visit
>> >> http://lists.contesting.com/mailman/listinfo/rfi
>> >> or, via email, send a message with subject or body 'help' to
>> >> rfi-request@contesting.com
>> >>
>> >> You can reach the person managing the list at
>> >> rfi-owner@contesting.com
>> >>
>> >> When replying, please edit your Subject line so it is more specific
>> >> than "Re: Contents of RFI digest..."
>> >>
>> >>
>> >> Today's Topics:
>> >>
>> >> 1. Re: LED Lights (Gary Johnson)
>> >> 2. led lights (Leonard Keepers)
>> >> 3. Re: LED Lights (Dale Johnson)
>> >>
>> >>
>> >> ----------------------------------------------------------------------
>> >>
>> >> Message: 1
>> >> Date: Fri, 20 Dec 2019 07:26:49 -0800
>> >> From: Gary Johnson <gwj@wb9jps.com>
>> >> To: Dale Johnson <dj2001x@comcast.net>
>> >> Cc: Leonard.Keepers@comcast.net, rfi@contesting.com
>> >> Subject: Re: [RFI] LED Lights
>> >> Message-ID: <506298B6-713A-4F5E-810E-CC5CCF50CFBD@wb9jps.com>
>> >> Content-Type: text/plain; charset=utf-8
>> >>
>> >> 1. What make and model? exactly.
>> >>
>> >> 2. How far are your antennas from those lights?
>> >>
>> >> I can also say with 100% confidence that a NOISY fixture will cause a
>> >> proximal RFI problem even if only one is installed.
>> >>
>> >> -Gary NA6O
>> >>
>> >>> On Dec 20, 2019, at 12:51 AM, Dale Johnson <dj2001x@comcast.net>
>> wrote:
>> >>>
>> >>> I have them in the shack for my desk lamp, no noise. Also have them
>> in
>> >> the basement on 24/7 no noise. My shop lights both garage and basement
>> >> shop are LED and no noise except don?t daisy chain them.
>> >>>
>> >>> Good luck
>> >>> Dale, k9vuj
>> >>>
>> >>>
>> >>>
>> >>> On 19, Dec 2019, at 22:04, Gary Johnson <gwj@wb9jps.com> wrote:
>> >>>
>> >>> Simple. Avoid fixtures. I have yet to find one that is acceptably
>> quiet.
>> >> Use medium-base screw-in bulbs, per the list at the bottom of my RFI
>> > page.
>> >>> http://wb9jps.com/Gary_Johnson/RFI.html
>> >>>
>> >>> Gary NA6O
>> >>>
>> >>> Hello all could someone suggest where to get LED light that do not
>> >>> generate RFI and a place where these lights can be purchased.Thank You
>> >>>
>> >>> Leoard
>> >>> _______________________________________________
>> >>> RFI mailing list
>> >>> RFI@contesting.com
>> >>> http://lists.contesting.com/mailman/listinfo/rfi
>> >>>
>> >>
>> >>
>> >>
>> >>
>> >> ------------------------------
>> >>
>> >> Message: 2
>> >> Date: Fri, 20 Dec 2019 10:39:49 -0500
>> >> From: Leonard Keepers <Leonard.Keepers@comcast.net>
>> >> To: RFI@contesting.com
>> >> Subject: [RFI] led lights
>> >> Message-ID: <194ce92c-52e3-9654-b9f9-d32b1629ab35@comcast.net>
>> >> Content-Type: text/plain; charset=utf-8; format=flowed
>> >>
>> >> hello i thank everyone that replied to me on led lights greatly
>> > appreciated
>> >>
>> >> Leonard
>> >>
>> >>
>> >>
>> >> ------------------------------
>> >>
>> >> Message: 3
>> >> Date: Fri, 20 Dec 2019 10:31:49 -0600
>> >> From: Dale Johnson <dj2001x@comcast.net>
>> >> To: Gary Johnson <gwj@wb9jps.com>
>> >> Cc: rfi@contesting.com
>> >> Subject: Re: [RFI] LED Lights
>> >> Message-ID: <6028E845-5071-4499-9631-00F8BA170E71@comcast.net>
>> >> Content-Type: text/plain; charset=utf-8
>> >>
>> >> Feit Electric at the LED?s that I have in the shack lamp and other
>> places
>> >> in the house. There are two in the basement that I never shut off.
>> The
>> >> shop lights are also Feit Electric. My doublet goes over the house at
>> >> about 30 feet, it?s 140 feet long with open feeders. The yagi is a
>> > SteppIR
>> >> at about 40 feet now and the tower base is about 35 feet from my shack
>> >> window. When I turn on the lights I don?t hear any increase in the
>> noise
>> >> floor here which is pretty quiet here for being in a city. Noise
>> floor
>> >> right now on 20 meters is about S-2 to S-3 on my K3 with no
>> attenuation,
>> >> preamp off. If I turn the yagi South the noise floor increases, I
>> > believe
>> >> it?s from my neighbors next door (200 ft) or beyond, but not from my
>> own
>> >> house.
>> >>
>> >> Dale, K9VUJ
>> >>
>> >>
>> >>
>> >> On 20, Dec 2019, at 9:26, Gary Johnson <gwj@wb9jps.com> wrote:
>> >>
>> >> 1. What make and model? exactly.
>> >>
>> >> 2. How far are your antennas from those lights?
>> >>
>> >> I can also say with 100% confidence that a NOISY fixture will cause a
>> >> proximal RFI problem even if only one is installed.
>> >>
>> >> -Gary NA6O
>> >>
>> >>> On Dec 20, 2019, at 12:51 AM, Dale Johnson <dj2001x@comcast.net>
>> wrote:
>> >>>
>> >>> I have them in the shack for my desk lamp, no noise. Also have them
>> in
>> >> the basement on 24/7 no noise. My shop lights both garage and basement
>> >> shop are LED and no noise except don?t daisy chain them.
>> >>>
>> >>> Good luck
>> >>> Dale, k9vuj
>> >>>
>> >>>
>> >>>
>> >>> On 19, Dec 2019, at 22:04, Gary Johnson <gwj@wb9jps.com> wrote:
>> >>>
>> >>> Simple. Avoid fixtures. I have yet to find one that is acceptably
>> quiet.
>> >> Use medium-base screw-in bulbs, per the list at the bottom of my RFI
>> > page.
>> >>> http://wb9jps.com/Gary_Johnson/RFI.html
>> >>>
>> >>> Gary NA6O
>> >>>
>> >>> Hello all could someone suggest where to get LED light that do not
>> >>> generate RFI and a place where these lights can be purchased.Thank You
>> >>>
>> >>> Leoard
>> >>> _______________________________________________
>> >>> RFI mailing list
>> >>> RFI@contesting.com
>> >>> http://lists.contesting.com/mailman/listinfo/rfi
>> >>>
>> >>
>> >>
>> >> _______________________________________________
>> >> RFI mailing list
>> >> RFI@contesting.com
>> >> http://lists.contesting.com/mailman/listinfo/rfi
>> >>
>> >>
>> >>
>> >> ------------------------------
>> >>
>> >> Subject: Digest Footer
>> >>
>> >> _______________________________________________
>> >> RFI mailing list
>> >> RFI@contesting.com
>> >> http://lists.contesting.com/mailman/listinfo/rfi
>> >>
>> >>
>> >> ------------------------------
>> >>
>> >> End of RFI Digest, Vol 203, Issue 49
>> >> ************************************
>> >>
>> > _______________________________________________
>> > RFI mailing list
>> > RFI@contesting.com
>> > http://lists.contesting.com/mailman/listinfo/rfi
>> >
>> >
>> _______________________________________________
>> RFI mailing list
>> RFI@contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
>>
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