On 10/22/2020 7:36 AM, Michael Walker wrote:
John
I have to say that 80% of the noise that impacted me on the low bands (and
even 2M) was in my house.
Yes, the stuff in our own homes is often our worst enemy!
I spent a few days going around with a Handheld that had AM on it and
narrowing it down. I replaced about a dozen wall chargers (Garmin and
Apple being the worst).
I have boxes of vintage linear supplies that I use to replace the
switching supplies that come with almost anything we buy.
I added Mix 31 and 43 chokes to both ends of every feedline depending on
the frequency. This also includes DC power cables. I ended up buying
about 100 of each and I have used most of them.
#43 cores are a poor choice for the HF bands.
It was the Yankee Contest Clipper Club document on choking that got me to
dig in further into my own home.
Here's my tutorial on the topic. It shows how to identify noise sources
and kill them. It ran in NCJ several years ago.
http://k9yc.com/KillingReceiveNoise.pdf
73, Jim K9YC
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