Gary,
Short answer to your question: NO. "Hospital grade" is a SAFETY issue, not an
RFI issue. Those green dots on hospital grade electrical connectors and
equipment means that the items have met certain specifications applicable to
the hospital environment, including AC power leakage current - an important
spec for anything that connects or touches a patient's body.
Other than military specs, such as MIL-STD-461, the Part 15 Class B and A
limits are what there is. Period. We would all be happier hams if all
consumer electronics met the 461 levels of radiated and/or conducted emissions,
which are designed to allow co-located systems on a common platform.
(Translation: multiple electronic systems on the same vehicle, in the same
building, or on a person.) Problem: no one could afford to buy anything. Part
15 limits do reduce interference between Part 15 devices, but have little hope
of reducing RFI to radio operations because of the allowable limits. Note that
Class B-rated devices are for home or office use, Class A-rated devices are for
commercial and industrial use, and those limits are even higher. That is why I
can detect point of sale systems in gas stations, banks, and Walgreens Drug
Stores at a block or more distant with my 2m/70cm mobile FM rig.
As I have posted here before, one significant problem with some of the consumer
grade garbage is the fact that some off-shore (you know who I mean) producers
are prone to submitting an item for FCC approval testing, win approval, then
alter the regular production units by leaving out the EMC components to save
costs. It is precisely those turkeys whose products need to be reported and
confiscated. BTW: Yes, I have personally seen altered equipment. Easy to
spot, but you have to usually cut them open or break their housings to see the
pc boards inside. You will find jumper wires in place of missing inductors and
vacant solder pads where by-pass caps should have been placed. A sickening
sight.
With all of the weeping and wailing going on in this thread, I make one modest
suggestion: before saying that a certain piece of consumer electronics is junk
that needs to be tossed, you need to confirm if it actually does bear an FCC
marking (meaning it passed Class B or A) AND then you need to determine if it
is one of those altered products I described above. Keep in mind that actual
Class B limits are around 30 dB (or worse) above the MIL-STD-461F limits. It
can take a LOT of design technique and hardware implementation (all spelled
"$$$") to get rid of those extra 30 or so dB of noise.
Finally, keep in mind that YOU can not stop emissions from your neighbor's junk
at your end. The solution is to apply fixes at the source, as Jim, K9YC, has
said so many times on this forum. That means winning the cooperation of your
neighbors and (probably) paying for the materials to make the fix. The "good"
news is that the farther you are from the neighbors, the less "fix" required.
-----Original Message-----
>From: Gary Smith <wa6fgi@yahoo.com>
>Sent: Feb 12, 2014 10:52 AM
>To: rfi@contesting.com
>Subject: Re: [RFI] LED Bulbs
>
>Would it be a better idea if we hams suggested that our neighbors look
>for "hospital grade" electronic and electrical devices?
>
>I have done my best to "educate' my neighbors, this has helped over the
>long haul somewhat.
>
>Gary...wa6fgi
>
>
>
>On 2/12/2014 7:43 AM, CR wrote:
>> This may be a good one to complain about anyway given the broad
>> spectrum of interference reported; it will affect broadcast, air to
>> ground communications, police, fire and commercial radio reception as
>> well.
>>
>> FWIW, Part 97 is not where you should look for illumination devices;
>> look in Part 18. Harmful interference *is* unlawful.
>>
>>
>> Cortland Richmond
>>
>> PS: Apologies for mistaking you for the other Dale. He and I have been
>> working in EMC for years.
>>
>> On 2/12/2014 10:25 AM, Dale J. wrote:
>>> Hi Roger,
>>>
>>> Now that statement I'll agree with. I will too.
>>>
>>> Even if I were to call the FCC to complain would I talk to a live
>>> human who knows what I'm talking about or would it be a robot that
>>> directs me to a FAQ on how to deal with RFI.
>>>
>>> 73
>>> Dale, K9vuj
>>>
>>>
>>> On 12, Feb 2014, at 8:12, Roger D Johnson<n1rj@roadrunner.com> wrote:
>>>
>>>> >Unfortunately, interference to amateur radio appears to be VERY low
>>>> >on the FCC priorities list. I'll probably be an SK long before they
>>>> >act on my complaint!
>>>> >
>>>> >73, Roger
>>
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>
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