[ADXA] noise issue - take 2

[w5zn at w5zn.org]

That should have read "and NOT one in an isolated small segement"

73 Joel W5ZN/ZF2ZN

-----Original Message-----
From: adxa-bounces at mailman.qth.net <adxa-bounces at mailman.qth.net> On Behalf
Of Joel Harrison, W5ZN via ADXA
Sent: Monday, March 23, 2026 4:27 PM
To: 'Jussi Eloranta' <eloranta at aa6kj.hopto.org>; 'ADXA'
<adxa at mailman.qth.net>
Subject: Re: [ADXA] noise issue - take 2

Jussi,

That is NOT power line noise. That is a noise being generated from another
source likely from inside your home and could be a number of things but I
can tell you that is NOT power line sparking noise.

You are correct, power line noise will occur over a broad range of
frequencies and one in one isolated small segment. Start turning things off
inside your home and shop and see if it disappears.

73 Joel W5ZN/ZF2ZN

-----Original Message-----
From: adxa-bounces at mailman.qth.net <adxa-bounces at mailman.qth.net> On Behalf
Of Jussi Eloranta via ADXA
Sent: Monday, March 23, 2026 3:45 PM
To: 'ADXA' <adxa at mailman.qth.net>
Subject: [ADXA] noise issue - take 2

Hi,

Just recorded the 160m noise on the panadapter. I was expecting it to be
wide and all over the place. However, see attached. Bog is beverage on
ground (wideband resonant) and invL is my inverted L (narrow resonant; SWR
only OK at the bottom of 160m). You can see that both spectra are
surprisingly narrow. They have center around 1.840 MHz (FT8 160m frequency,
of course!) and extend to the sides by about 100 KHz. I was initially
looking at this with my inv L and thought that, OK, that must be just the
antenna response I am seeing. But now that I see the same thing with the
BOG, I am not so sure what to make of this. If I scan more to the AM band,
it seems that it is clear over there but then going further down in
frequency I find another similar spot that is noisy.

So, is this power pole noise after all? And if not, what on earth could it
be? It has the characteristic raspy tone with multiples of 60 Hz in it. On
AM it sounds like the typical power line hum. All that fit power pole noise
but the spectrum does not - I think. Furthermore, I do not hear this noise
at all on 80m. This is not from my shack as I have turned off power and used
the radio on battery power. I do hear something weak on 6m from far away but
I have no idea if this is the same thing as what I see on 160m.

Jussi (aa6kj)

______________________________________________________________
ADXA mailing list
Home: http://mailman.qth.net/mailman/listinfo/adxa
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:ADXA at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html