I might... have found the cause of the
signals I've been seeing that were so
symmetrical as originally described and
seen in the photos of the P3 SVGA
monitor.
To cut to the chase, a problem I've had
with getting my K3 to lock onto a good
10MHz source turns out to be because the
new & tighter TCXO in the K3 has failed. I
replaced the newer .1 TXCO with the
original and all of my syncing issues have
resolved. I am also (so far) not seeing
the "grid looking" interference I've been
having. This explains why I have not been
able to track the source, it was in the
radio itself...
Fingers crossed...
73,
Gary
KA1J
> Folks,
>
> Apologies for not replying earlier to the
> helpful suggestions. I meant to reply and
> got sidetracked.
>
> I found my portable SW radio wasn't able
> to pick up signals in the 160M band, it
> leaves a big hole in reception and worse,
> no option for a directional antenna. As
> this interference stops just above the AM
> broadcast band, that radio was mostly
> useless in RFI finding.
>
> However, I just bought an interesting
> portable receiver that might well be what
> I need. It's a County Comm "general
> purpose World Receiver". A handheld
> digital unit that comes with an attachable
> ferrite antenna as well as a built-in
> extendible antenna.
>
> As with all things digital, it's not plug
> & play, I have found time consuming ways
> to get the frequency & mode to select what
> I want but I'll keep reading the manual
> and find the quick easy method.
>
> I'll check out the neighborhood when the
> interference is there & I'll see what I
> find.
>
> If/when I find something I'll keep you
> posted.
>
> 73,
>
> Gary
> KA1J
>
>
> > From the hand drawing of the noises, it looks as if there may be two
> > different noises.
> >
> > Most of the time, noise sources spaced 10 to 100 kHz apart are
> > switching power supplies or similar devices. They exhibit the
> > following characteristics:
> >
> > 1. The noise appears at intervals across a band, typically 10 to 100
> > kHz apart. 2. The noise can be very carrier like, but usually is
> > not, having a strong 6o- or 120-Hz component to it. This is usually
> > best determined by listening to the noise in the AM mode. 3. There
> > is no "digital" sound to the noise, with nothing that sounds like
> > data being transmitted. 4. Switching devices are usually a little
> > drifty, so the frequency one occupies tends to drift up and down as
> > the temperature of the device varies. 5. Switchers are also
> > sensitive to line voltages, so glitches such as power surges or dips
> > will usually cause a brief frequency change from time to time.
> >
> >
> > Ed, W1RFI/0
> > ________________________________________
> > From: RFI [rfi-bounces@contesting.com] on behalf of Cortland
> > Richmond [ka5s@earthlink.net] Sent: Sunday, October 28, 2018 4:34 PM
> > To: rfi@contesting.com Subject: Re: [RFI] Signals on 160
> >
> > Ed will remember the AT&T modems on 80 meters.
> >
> > I had good luck tracking them down in Petaluma and locating each one
> > to specific rooms in a development of single-story duplexes.
> >
> > It was Super Bowl Sunday and when people sharing cable co. services
> > saw someone with antennas on his car and a "sniffer" (AOR 8000 with
> > an untuned loop) they were running behind their houses to remove the
> > illegal taps.
> >
> > A 3-6 inch loop of rigid or even fairly stiff coax can be directive
> > enough to find these harmonics and then at lower frequencies march
> > right up to the source. H-field coupling drops off VERY fast away
> > from a radiating conductor.
> >
> > Cortland
> > KA5S
> >
> >
> > On 10/28/18 3:54 PM, Hare, Ed W1RFI wrote:
> > > "What is it?" is the wrong question. If someone said that it is a
> > > model Z-123 Netstuff modem, that really wouldn't help much. The
> > > real question is: "Where is it?" Finding the house or location
> > > where the noise is originating is what you will get to eventually,
> > > so start with that question.
> > >
> > > Many noisy devices can sound similar, so if someone tells you that
> > > it is a Z-123, and it is really a lighting ballast instead, you
> > > will be on a wild-goose chase.
> > >
> > > Ed, W1RFI
> > >
> > >
> > > ________________________________________
> > > From: RFI [rfi-bounces@contesting.com] on behalf of
> > > donovanf@starpower.net [donovanf@starpower.net] Sent: Sunday,
> > > October 28, 2018 3:04 PM To: rfi@contesting.com Subject: Re: [RFI]
> > > Signals on 160
> > >
> > > Hi Gary,
> > >
> > >
> > > Of course, the first thing you should do is turn off all of the AC
> > > power -- including UPSs -- in your own home to determine if any of
> > > the RFI disappears.
> > >
> > >
> > >
> > > I don't think anyone will be doing you a favor by helping you
> > > guess what these signals might be. By far the best way to
> > > determine what they are is to build -- or if necessary buy -- a
> > > simple small loop antenna. A loop antenna has a deep, narrow
> > > azimuth null off of each side of the antenna that allows to
> > > quickly identify the RFI source.
> > >
> > >
> > > Good luck!
> > >
> > >
> > > 73
> > > Frank
> > > W3LPL
> > >
> > > ----- Original Message -----
> > >
> > > From: "Gary Smith" <Gary@ka1j.com>
> > > To: rfi@contesting.com
> > > Sent: Sunday, October 28, 2018 5:31:51 PM
> > > Subject: [RFI] Signals on 160
> > >
> > > I've been encountering some strong signals
> > > on 160 recently. I made some approximate
> > > guesses at the frequency using the P3
> > > markers to measure them. Here's the
> > > signals at 1:20PM local time with a center
> > > frequency of 1.848.67
> > >
> > > The main signals are about 42 KHz apart.
> > > The lesser spikes in-between appear at
> > > somewhat regular intervals.
> > >
> > > http://doctorgary.net/spikes-on-p3.jpg
> > >
> > > Here's the measured values of the main
> > > signals
> > >
> > > http://doctorgary.net/frequencies.jpg
> > >
> > >
> > > Any idea what might be the source of
> > > signals spaced like this?
> > >
> > > 73,
> > >
> > > Gary
> > > KA1J
> > > _______________________________________________
> > > RFI mailing list
> > > RFI@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/rfi
> > >
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> > >
> >
> > _______________________________________________
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>
>
>
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