[TowerTalk] Noise Profiles....

[Ed Sawyer]

Message: 5

Date: Sun, 15 Jan 2017 11:31:43 -0500

From: Paul Plants <w3plp at verizon.net>

To: w5prchuck at gmail.com

Cc: Jim Thomson <jim.thom at telus.net>,       "towertalk at contesting.com"

            <towertalk at contesting.com>

Subject: Re: [TowerTalk] noise profiles...

Message-ID: <E043185A-6C48-4CE2-9EE9-66277B04B340 at verizon.net>

Content-Type: text/plain; charset=utf-8

 

 

Paul, 

 

If you are driving around with an HF rig in your neighborhood, you will have
a hard time finding interference that way.  What I usually assume is that
the noise source is generating signals in the UHF spectrum as well.  I tend
to walk, not drive, around with a 450Mhz Yaesu HT that has AM mode -
connected to a 6 el hand held yagi - and headphones.  As you walk past each
pole, transformer, and house, point the yagi at the items to see if any
noise rises up from the noise floor.  Typically - interference is no more
than 1 mile from your house (air mile) - often closer - if its S7+.  I have
yet to not find the offender using this method.  Once a suspecting source
has been zero'd in on, use the "deep null" feature of a 6 el yagi and see
where the nulls are (better rays than the max gain of the yagi).  Try and
identify the source from at least 3 different sides to be sure its actually
where you keep thinking it is - often its not quite where you thought it
was.

 

73

 

Ed  N1UR

 

 

Paul

W3PLP

Sent from my iPad Air 2

 

> On Jan 15, 2017, at 11:18 AM, <w5prchuck at gmail.com> <w5prchuck at gmail.com>
wrote:

> 

> ?I have a noise, what do you think it could be?? doesn?t give us much to
go on. Can you give us more information?

> 

> Does the signal level vary with frequency?  No

> Does the level vary with direction?  No

> How are you looking for it? With what? Yeasu ssb radio

> Surely it must be somehow localized to some area. How big? So far 2 mile
radius and still looking

> Have you checked close to power lines? Is it louder there?  No

> Have you checked close to cable tv lines? No

> Have you determined it is not in your shack? Not.  Did pull mains three
times

> 

Signal drops off sharp below 18 MHz and above 30 mhz

>