[RFI] A Bizzare EMI Story

[Les Cockram]

Front page article in today’s WSJ concerning am radio rfi in EV vehicles.
Find an easy cure and you will a rich person.

Sent from LTC


> On Nov 7, 2018, at 11:29, David Eckhardt <davearea51a at gmail.com> wrote:
> 
> Electronic 'mosquitoes' (RFI producers) make wonderful objects for target
> practice....
> 
> Dave - WØLEV
> 
>> On Wed, Nov 7, 2018 at 4:41 AM Mike NA6MB <na6mb.mike at gmail.com> wrote:
>> 
>> I vote hammer !
>> 
>> NA6MB
>> 
>> 
>> 
>>> On 11/6/2018 7:30 PM, donovanf at starpower.net wrote:
>>> From: "Sam Josuweit" <samjos at epix.net>
>>> To: topband at contesting.com
>>> Sent: Wednesday, November 7, 2018 2:15:35 AM
>>> Subject: Topband: Bizzare EMI Story
>>> 
>>> So after taking a few years off from radio, over the summer I decided to
>>> rebuild my station and antennas and get back on the air. Was doing fine
>>> until a few weeks ago, my noise level was S9 on 80 meters. Using a
>> beverage
>>> it was ok but on my TX antenna it was 120hz hash. I tried everything to
>>> locate the source, unplugged computers, Directv, DSL modem, freezer you
>> name
>>> it, checked my entire ground system, it still was there. To make matters
>>> worse after listening to it on AM I noticed I could hear the local NOAA
>>> Weather radio station, which is on 162.55 MHZ FM! Now the local
>> transmitter
>>> for NOAA is on the next mountain over and line of site with my remote
>> QTH,
>>> but 162MHZ to 3.7MHZ?? This really had me stumped, and I was just about
>> to
>>> give up. I have an old farm house and don't have too many power outlets,
>> but
>>> I realized I missed checking the one in our bedroom, and there sits my
>> NOAA
>>> weather alert radio. Unplugged it and the hash was gone. Since these
>> radios
>>> monitor constantly for alerts, they must just mute the audio when not in
>>> use. Apparently something in the radio power supply failed causing the
>> power
>>> noise, which was then getting modulated by the muted audio. This was
>>> propagating thru my whole electrical system. I'm just glad I found it.
>>> Debating if I should take a look at the weather radio or smash it with a
>>> sledge hammer.
>>> 
>>> Sam (N3XZ)
>>> 
>>> _______________________________________________
>>> RFI mailing list
>>> RFI at contesting.com
>>> http://lists.contesting.com/mailman/listinfo/rfi
>> 
>> --
>> Thanks,
>> Mike
>> NA6MB
>> 
>> _______________________________________________
>> RFI mailing list
>> RFI at contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
>> 
> 
> 
> -- 
> 
> *Dave - WØLEV*
> *Just Let Darwin Work*
> *Just Think*
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