KB6NU's Ham Radio Blog

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FCCs OET clarifies emissions compliance testing for RF LED lighting devices

Posted: 04 Jul 2016 05:47 PM PDT
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Have any of you had RFI problems with your LED lights? I havent here.Dan

QST de W1AW

ARRL Bulletin 22 Â*ARLB022

From ARRL Headquarters

Newington CT Â*June 30, 2016

To all radio amateurs

SB QST ARL ARLB022

ARLB022 FCCs OET Clarifies Emissions Compliance Testing for RF LED Lighting
Devices

The FCCs Office of Engineering and Technology (OET) has clarified that all
RF LED lighting devices falling under Part 15 rules as unintentional
radiators must meet conducted and radiated emissions limits set forth in
those rules.

Operation of Part 15 unintentional radiators is subject to the condition
that no harmful interference is caused, the OET reminded, in a knowledge
database paper released on June 17. Manufacturers and users should
therefore note that lighting devices are required to cease operation, if
harmful interference occurs.

The OET said radiated emissions measurements must be performed at least
from 30 MHz to 1000 MHz to adequately demonstrate compliance with Part 15
(15.109). Its guidance, the OET continued, applies to RF LED lighting
devices that, in the past, have been considered to operate on frequencies
below 1.705 MHz. Previously, devices operating between 9 kHz and 1705 kHz
had to be tested only for radiated emissions up to 30 MHz, where no
specified radiated emissions limits exist, and were exempt from testing
from 30 MHz to 1000 MHz. The OET said it recognizes that routine radiated
emissions measurements are needed under Part 15, based on the highest
frequency generated or used in the device.

[W]e have found that emissions from RF LED lighting devices are
non-periodic, broadband in nature, and are produced as a byproduct of the
internal driver circuitry within the RF LED lighting device, the OET
knowledge database paper said. These types of emissions have adequate
energy and potential to generate radiated emissions well above 30 MHz.

The ARRL Labs Electromagnetic Compatibility Engineer Mike Gruber, W1MG,
said he was pleased to see the FCCs OET clarify the test measurement
requirements. He said ARRL is generally hearing more RFI complaints
stemming from RF LED bulbs.

Not only are the emissions limits higher for Part 15 LED bulbs as opposed
to Part 18 fluorescent and CFL bulbs, they seem to be winning out in terms
of consumer popularity, Gruber said. Higher limits and more bulbs probably
make for more complaints. Gruber said the Lab has seen LED lighting devices
causing problems in the 2 meter band. Since conducted emissions limits do
not apply above 30 MHz, radiated emissions limits can be the first line of
defense against RFI at these higher frequencies.

Gruber pointed out that noise generated by street and traffic lighting can
be widespread. In such instances, he suggested that Part 15b limits for
residential areas should apply. These limits are lower than Part 15a
limits, which are intended only for commercial and industrial environments,
he explained. This is especially critical in cases where a pole transformer
connected to the lighting device also feeds a home or residence. The 240 V
split-phase secondary system can conduct RF into a residence through the
service entrance panel. He suggested that the lower limits may benefit
mobile users.

The OET noted that the ANSI Accredited Standards Committee C63-EMC is
drafting measurement procedures for lighting devices. When complete, we
expect it will address in greater detail the measurement procedures and
configurations to be used in determining compliance, the OET said.

NNNN

/EX



The post FCCs OET clarifies emissions compliance testing for RF LED
lighting devices appeared first on KB6NUs Ham Radio Blog.


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Operating Notes: A special (event) July 4th weekend

Posted: 04 Jul 2016 11:37 AM PDT
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This weekend was a specialÂ*(event) weekend here at KB6NU. It all started
out byÂ*working K2I (NJ) and K2A (NY) Friday evening as part of the 13
Colonies Special Event. I had participated in this event before, but never
worked very hard at it, and as a result, always failed to work all 13
colonies.

This year was different, though. This year, I was determined to work all of
them, and by Saturday afternoon, using a combination of phone and CW
contacts, I had.

I kept going, though. I had already worked several of the stations on both
phoneÂ*and CW, so I figured that if I kept at it, I probably could work all
of them on both phone and CW. When I called it quits on Saturday evening, I
needed only seven contacts—four on phone and three on CW—to complete the
dual clean sweep.

I picked up a couple more Sunday morning, then went to visit my in-laws.
When I returned later in the evening, I settled in to finish off the clean
sweeps. An hour and a half later, at 0318Z, I worked K2D (CT) on 75m phone,
completing the job.

Overall, Id guess that I spent about six hours accomplishing this task, and
it was great fun. Thanks to all the operators that worked the K2* stations.

Here are a few observations:

The event has become very popular. Some of the stations generated huge
pileups, especially when they first came on the air. Generally, I joined
the pileups, but if I failed to make contact after a couple of calls, I
tuned around for other stations that I needed, then came back after a half
hour or so. That strategy worked a couple of times—when I returned, the
pileup was a lot smaller and it was easier to get through. Sometimes,
though, there was still a huge pileup.
Some of the K2* operators were really good. Some werent. This isnt a big
complaint, but the phone operators should be advised to callÂ*by call areas
when there is a big pileup. Several of the guys did this when they were
innundated with stations calling, and it madeÂ*a lot easier for them and for
the guys trying to make contact with them.
None of the CW stations that I contacted worked split, even when there was
a big pileup. I know that split operation might not be a skill that many
ops are familiar with, but many W1AW/p operators, including me, used it and
it really is the way to go to efficiently work CW pileups.
I discovered a new DXSummit.fi feature that really helped me. I dont know
why I didnt know about this until just now, but you can search the spots on
DXSummit by callsign. This was especially useful as I was getting down to
the last few K2* stations. I guess that you can also include mode in the
search, but I didnt take the time to figure out how to do that.



But, wait! Theres more!

Saturday afternoon, while searching for the 13 Colonies stations, I ran
across three otherÂ*special event stations, including two NPOTA stations:

K4RC operating from TR23,Â*Washington-Rochambeau Revolutionary Route
National Historic Trail.
W3GKN, operating from theÂ*Gettysburg National Military Park.
W1G, also operating from Gettysburg. This appears to be a labor of love by
Bob, WO4L, and an attractive certificate that includes the text of Lincolns
Gettysburg Address is available. Bob will be operating until July 10, so
theres still plenty of time to work W1G.


Special events are just that. Thanks to all the operators who made my
weekend special.

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on KB6NUs Ham Radio Blog.