We have measured a number of LED bulbs here in the ARRL Lab. They range from
essentially zero noise to way over the FCC limits. The good news is that all
of the ones we have tested *so far* that are being sold in the big box stores
do meet the FCC emissions limits. The outliers are being sold elsewhere,
including eBay. One just sent to us for testing is 26 dB over the emissions
limits. It is causing bad interference. With an actual interference case and
measurements well above the FCC limits, ARRL is going to file a formal
complaint on this one.
Of note, meeting the FCC limits is not a guarantee at all of no interference.
The limits below 30 MHz are for noise conducted onto the AC mains only. There
are no limits for radiated emissions below 30 MHz or limits on the amount of
noise that can be put on the secondary of devices such as some kitchen lights
that have a power supply and run wires to the actual LED bulbs.
Generally, the rules do prevent a lot of interference, and if there is
interference from a neighbor's device, it is going to be close to you and
easier to find.
To be marketed, several criteria apply.
* For LED bulbs and systems to be marketed to consumers, the design must be
tested by the manufacturer to meet the FCC Part 15 Class B limits. For
fluourescent bulbs, they must meet Part 18 consumer limits. Class A or
non-consumer devices to do exist, bt they are supposed to be marketed only for
use in commercial environments. Lowe's and Home Depot sell "commercial" units
openly, so be wary.
* They must be marketed with the FCC logo and the language described earlier on
a label on the product or, if the product is small, in the documentation.
* These are the responsibility of the manufacturer and marketer. The end user
of the product is responsible under FCC rules for using it in a way that does
not cause harmful interference to licensed radio.
The latter point is really hard to communicate to neighbors, so be prepared to
explain why a device they just bought at Home Depot is in violation of some
federal law that they don't understand.
Ed Hare, W1RFI
ARRL Lab
-----Original Message-----
From: RFI <rfi-bounces+w1rfi=arrl.org@contesting.com> On Behalf Of Michael Tope
Sent: Sunday, January 30, 2022 2:53 PM
To: David Eckhardt <davearea51a@gmail.com>
Cc: RFI <rfi@contesting.com>
Subject: Re: [RFI] IR Illuminator for Security Cameras
Thank you, Dave. Yeah, I understand that this warning is somewhat perfunctory,
but it was so prominently displayed in the manual and a friend was just
complaining about RFI from LED lights. Those two things got me to wondering if
these things (IR LED arrays) are a know problem child, or just one of the many
things that can be a problem, but not always are a problem. This one takes +12V
input, so I suppose the risk is low that the array itself is going to be an
interference source. I assume the RFI problem with LED lights is actually the
switchers that supply them rather the the semiconductors themselves and I can
always use a cleaner external supply if the one that comes with this unit is
junk.
73, Mike W4EF.........................
On 1/30/2022 11:03 AM, David Eckhardt wrote:
> There is a standard FCC paragraph required for all Part 15, Class B
> (Home and Small Office) products. It's required by FCC. No big thing.
>
> Here is the required statement:
>
> 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.
>
>
> Dave - WØLEV
>
> On Sun, Jan 30, 2022 at 6:56 PM Michael Tope <W4EF@dellroy.com> wrote:
>
> I have a couple of south facing security cameras that I have tucked
> under the soffits of my high desert cabin so they don't get baked
> by the
> high desert sun. The tradeoff for this is that I am getting glare off
> the soffit from the camera's built-in IR LED arrays which spoils the
> night vision image quality. I am thinking of purchasing some
> external IR
> LED arrays to solve this problem.
>
> I found a positive review of this illuminator, but I got a little
> worried when I saw the FCC part 15 warning prominently displayed
> in the
> user manual:
>
>
> https://www.amazon.com/CMVision-IRP12-850nm-WideAngle-Power-Illuminator/dp/B00Q156IPE/ref=as_li_ss_tl?ie=UTF8&qid=1503002750&sr=8-1&keywords=irp12-850&linkCode=sl1&tag=stf03-20&linkId=1ea87920d2d4d067e723c3100182acbe
>
> <https://www.amazon.com/CMVision-IRP12-850nm-WideAngle-Power-Illuminat
> or/dp/B00Q156IPE/ref=as_li_ss_tl?ie=UTF8&qid=1503002750&sr=8-1&keyword
> s=irp12-850&linkCode=sl1&tag=stf03-20&linkId=1ea87920d2d4d067e723c3100
> 182acbe>
>
> I am not aware of any interference from the IR LED arrays that are
> built
> into the cameras, but just in case these illuminators are more
> problematic I thought I would run this by the reflector before I
> press
> the "add to cart" button.
>
> Thanks,
>
> Mike W4EF.................
>
> _______________________________________________
> RFI mailing list
> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>
>
>
> --
> *Dave - WØLEV*
> /*Just Let Darwin Work*/
>
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