[ADXA] Switching PS / wall warts

[Jon W. Reynolds]

You might get up with the DEA, I've heard (as I'm sure is fairly common knowledge) some home indoor pot farms have noisey led uv lamps. May be some truth to it, maybe more myth and legend! :)

Jon
KI5UCZ

-------- Original Message --------
On Tuesday, 11/18/25 at 09:33 w5znjoel at gmail.com wrote:

> You bring up an interesting point, Jussi, regarding line noise. There have been about a half dozen cases I’m aware of where a radio amateur was adamant a noise being experienced was line noise. The power company evaluated the situation and declared they could not locate any power line issue. Further investigation identified the source as a consumer device. In most cases, power line sparking and arcing will occur over all amateur bands, up into the UHF region where noise from a consumer device most likely will not.
>
> I have a noise to the east only on 160 meters that I originally believed to be power line noise since in that direction my antennas are looking directly perpendicular into the power lines down on the highway. That turned out not to be the case, but some device generating noise from one of the houses along the highway. After almost 7 years it disappeared last year but when I connected all of the receive antennas back up last month, it is back. I’m not exactly sure what it is or the exact house it is originating from (I have two suspects) but its not line noise and it increases my noise floor 20 dB on 160 meters to the east.
>
> Just another example that this is a never-ending battle with noise originating from many different sources. The lesson learned from your note is if a person is experiencing a “noise” issue, our usual first claim is “line noise” but today that’s not necessarily the case. Line noise has a lot of “competition” these days!! 😊
>
> I’ve said on several occasions that many years ago hams were the source of interference to TV’s, land line phones, etc. but today we’re the victim!
>
> 73 Joel W5ZN/ZF2ZN
>
> From: adxa-bounces at mailman.qth.net <adxa-bounces at mailman.qth.net> On Behalf Of Jussi Eloranta
> Sent: Tuesday, November 18, 2025 9:08 AM
> To: adxa at mailman.qth.net
> Subject: Re: [ADXA] Switching PS / wall warts
>
> On 11/18/25 08:13, w5znjoel at gmail.com wrote:
>
>> The topic involves much more than can be covered in an email. Maybe a program during a future meeting is in order.
>
> Yes, please :-)
>
> The noisy PS that I had generated has at 1.8 MHz and 3.5 MHz. Just the right places (not)! You can recognize it by the raspy tone. To the ear power line noise sounds similar.
>
> Jussi (aa6kj)
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