[amsat-bb] Re: Help with 75 mtr Qrn problem
i8cvs
domenico.i8cvs at tin.it
Sat Aug 3 13:47:35 PDT 2013
Hi Ernie, W8EH
I agree with your diagnosys and this is why I writes to Dave N6CO
the following information.
"To find out from where the noise come out you need a MFJ-852
Meter A/C Line Noise Meter visible in the following internet address:
http://www.mfjenterprises.com/Product.php?productid=MFJ-852
This instrument is currently used by the Electricity Power
Companies in England."
73" de
i8CVS Domenico
----- Original Message -----
From: "Ernie" <w8eh.ernie at gmail.com>
To: "Dave Larsen PhD" <doc at volcano.net>
Cc: <amsat-bb at amsat.org>
Sent: Saturday, August 03, 2013 4:52 PM
Subject: [amsat-bb] Re: Help with 75 mtr Qrn problem
> Dave,
>
> I had a similar problem on 80 meters at my QTH. The power company
> couldn't find it. I finally did. I drove the entire area mobile with my
> 706, trying different bands. Having 2 meter and 70 cm fox hunt antennas,
> equipment and attenuators helped me a lot too.
>
> The QRN signal on 80 was very high here, about 40-50 over s9. I finally
> found it over 6 blocks away. It was a lower 'static' line (neutral)
> touching a back support line, both ran between the two poles and crossed
> each other barely touching. The funny thing was, when I measured it the
> distance between the poles was about a half wave on 80/75. So the 'back
> guy' was a good half wave antenna on 80. And it was aimed my direction.
>
> My noise would go away when wet or damp and would get stronger when the
> sun came up and warmed everything and evaporated the moisture.
>
> Keep in mind, generally the noise won't be heard on the higher bands
> (430 mhz) unless you are less than a couple hundred feet away from the
> source. You can hear 80 meter noise from power lines over a half mile
> away. The closer you get to electrical noise, the higher in frequency
> you can 'usually' hear it.
>
> Once you find it, insist the power company see the before and after on
> your equipment. My contact here didn't believe that I could hear the
> noise that far away.
>
> Ernie W8EH
>
>
> > On 8/2/2013 6:23 PM, Dave Larsen PhD wrote:
> > I have 2 dipoles up at 60+ ft - one set running East-West other North
> > South .. From 2.6 to 5 Megs I have a S-7 Qrn lev at 4 Am .. buy
> > noon I have a 10-20 over QRN Lev .. I live on 10 acres and have
> > turned off main power to house and still have QRN .. so not coming
> > from anything in house .. This one has me stumped .. 6 moths ago
> > my Qrn was a S-2 .. waiting for a G6 radio to try and track this down
> > but does anybody else have any idea's ?
> >
> > Tnx
> >
> > Dave
> > N6CO
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