Hi Art,
If its any of your suspected sources you should be able to observe
spectral shape (signal strength variation vs. frequency) on a
panadapter or by simply turning the dial on your receiver.
If its a plasma TV it shouldn't present 24 hours per day, it will follow
some kind of human life pattern. Computer power supplies, wall
warts, and battery chargers are common problems too, but they all
have distinct observable spectral shapes.
I once had intense RFI from an electric fence a mile away with
its fence charger stuck ON (not pulsing). It sounded just like AC
power line RFI except for the peculiar characteristic that it was
extremely intense on 160 meters and couldn't be heard at all on
any other ham band.
Good luck!
73
Frank
W3LPL
----- Original Message -----
From: "Art Snapper" <art@nk8x.net>
To: "Ed Stallman" <ed.n5dg@gmail.com>
Cc: topband@contesting.com
Sent: Saturday, March 12, 2016 8:24:32 PM
Subject: Re: Topband: A 160m Noise problem
I am trying to track down a similar issue. Some of it may be the neighbor's
plasma TV, but I also suspect DSL or Cable TV leakage. I have wandered
around with an FT-817 with a bcb loopstick antenna. No luck so far. My
noise has peaks in the 1823-1829 range. And, yes I hear it on both the 4sq
and the bog in the NE direction. Fortunately it isn't terribly strong.
GL de NK8X
ᐧ
On Sat, Mar 12, 2016 at 3:04 PM, Ed Stallman <ed.n5dg@gmail.com> wrote:
> Hello Topbanders
>
> I would like to explain my noise issue to get opinions on search and
> Destroy
>
> This noise is covering the 160m band only, 80m is good ! I'm using a HI-Z
> receive 4 SQ and the NW direction is as quiet can be . All other directions
> are noisy with the NE being the worst , SE almost as bad and SW is somewhat
> OK. The noise starts at 1780 Khz and rises quickly to its peak at 1820
> Khz ! from there the noise levels off to 1880 Khz and slowly drops to
> nothing at 2070 Khz ! Wish I could post a screen shot of my panadapter for
> y'all to see, I'll be happy to send JPG file off list !
> I was thinking maybe water in the RG6 and with the Bias T the Hi-Z uses,
> this may be my problem but disconnecting and testing all the coax using
> the 20meg scale ... all checks good ! I may replace the RG6 anyway but
> thinking of running a beverage at 165 degrees and see if the noise is still
> there . Was going to run the beverage anyway in hope of hearing Heard Is .
> At first I was thinking power line noise , I checked for noise using a
> 144Mhz AM receiver and 3 el yagi . I did find some noise to my NE but gone
> today after the big rain . 160m noise is still with me!
>
> Now I have parts ordered to build a small 160 loop . With that and my K3
> I'll move to different locations and see how that works out .
>
> Yes I have unplugged everything in the house and no switching supply's
> that we leave plugged in . With computers off and using VFO I can see the S
> meter rise and lower sweeping through the 160 band .
>
> I've ask 2 of my neighbors to disconnect their elec fence with no joy .
>
> I have to give my pasture a couple of days to dry out , then I'll run the
> beverage and replace the RG6 on the RX 4 SQ with new flooded coax .
>
> Oh and I also tried a BCB filter ..
>
> Any Ideas what could cause the 160 only noise ?
>
> Thanks Ed N5DG
>
>
> ---
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