Remember in his shack he has a very good radio and a very good antenna which
together increased sensitivity and allow him to hear much further away. when he
goes outside with a portable and a smaller antenna he doesn't have the
sensitivity he had inside there for he may have to travel a lot further before
he's able to receive it.
Be safe,
Mike
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On Mar 22, 2021, 11:37 PM, at 11:37 PM, Gary <gary_mayfield@hotmail.com> wrote:
>Kim,
>
> I hear it on the portable when connected to the vertical antenna, but
>will undertake an antenna substitution experiment this weekend.
>
>Keep the suggestions coming!
>
>73 and Thanks,
>Gary "Joe", kk0sd
>
>
>
>-----Original Message-----
>From: RFI <rfi-bounces+gary_mayfield=hotmail.com@contesting.com> On
>Behalf Of Kim Elmore
>Sent: Monday, March 22, 2021 4:44 PM
>To: Don Kirk <wd8dsb@gmail.com>
>Cc: Rfi List <rfi@contesting.com>
>Subject: Re: [RFI] New Interference at kk0sd
>
>That’s a great idea, too! I once ran into an interference problem that
>was inherent to the antenna, but only under certain conditions. It
>didn’t sound like Gary’s but I pulled a lot of hair out fixing that
>one. I’m simply suspicious that he hears NOTHING with his portable rx
>so I’m after eliminating anything inherent to his station. Standing by
>his vertical with his portable rx is a great idea.
>
>73,
>
>Kim N5OP
>
>"People that make music together cannot be enemies, at least as long as
>the music lasts." -- Paul Hindemith
>
>> On Mar 22, 2021, at 2:24 PM, Don Kirk <wd8dsb@gmail.com> wrote:
>>
>>
>> Hi Dave,
>>
>> I still recommend tuned and untuned loops to folks on an almost daily
>basis but they definitely don’t shed as much light on the situation as
>a unidirectional antenna does. It would be nice to see what your
>shielded untuned loop design is.
>>
>> The beauty of the portable flag which is unidirectional is that you
>typically can walk right to the source (no guessing which direction the
>signal is coming from). I still pack 7 antennas when I go on a RFI
>case, and this includes 3 tuned HF loops, but I have found that I
>typically don’t use bidirectional loops anymore (unless I’m trying to
>be more stealth) as the portable flag saves me an enormous amount of
>time. Also in heavily congested areas (like downtown Indianapolis)
>having the unidirectional HF antenna is priceless as it unmasks noise
>that’s mixing from other sources that are in the opposite direction,
>etc. Yesterday I worked on a case (more of a country setting) where I
>had 2 different bad poles that were only 0.14 miles apart plus a 3rd
>RFI source generating spikes every 1 KHz within the same area and
>having the unidirectional HF antenna helped me locate all 3 sources in
>a matter of minutes (way under an hour).
>>
>> You can never have enough antennas in your direction finding bag of
>tricks but after using a unidirectional HF antenna like the portable
>flag for direction finding I can’t imagine not using one. It typically
>takes me seconds to tell which direction the signal is without the need
>of triangulation, etc. Traditional triangulation has almost become a
>thing of the past for me.
>>
>> I also have been helping a ham that has the MFJ unit (the one with a
>beam and the one with a dipole) and while it has helped him, it has an
>odd characteristic that makes the meter jump which causes confusion to
>him and after looking at the schematic I question how they implemented
>AGC in those units. I’m starting to think AGC in a radio direction
>finding system is typically not desirable. Manual attenuation is
>priceless but I don’t want anything changing gain automatically.
>>
>> Just my opinion from tracking down RFI on an almost continuous basis
>in addition to my day job.
>>
>> Please share details on your shielded untuned loop and thanks.
>>
>> 73,
>> Don wd8dsb
>>
>>
>>
>>> On Mon, Mar 22, 2021 at 1:22 PM David Eckhardt
><davearea51a@gmail.com> wrote:
>>> We recently found a faulty lightning 'arrestor' on a pole by using
>>> both the MFJ device and a small shielded loop (easy home brew
>>> project) into a battery-powered receiver. We had two of us in the
>>> field. One wielded the MFJ and I had the small (0.5-meter) shielded
>
>>> loop fed into the Yaesu VR-500 on 1.830 MHz (160-meters). We both
>>> independently found the same source / pole in the field. The null
>on
>>> the shielded loop is extremely sharp and this piece of hardware
>>> should be in the bag of tricks of anyone sleuthing RFI. It is a
>>> powerful tool when coupled to a battery-powered receiver with its
>>> extremely sharp null (perpendicular to the plane of the loop). One
>doesn't need something as large as the 'Flag" that was recently
>published
>>> in QST and referred to in a previous post in this thread. Another
>plus
>>> for the shielded loop is that in the field, one can tune the
>receiver
>>> to the worst-case frequency of the RFI as I did in the related
>story, above.
>>> The shielded loop is untuned. The MFJ relies only on VHF noise.
>In some
>>> cases, an ultrasonic microphone at the focus of a small parabolic or
>
>>> spherical reflector is good at finding coronal discharges as well as
>
>>> active arcs and discharges. MFJ also makes that at a reasonable
>price.
>>>
>>> Our power provider was out the next day to fix the problem. We even
>
>>> gave them the pole number which is a great help to any power
>provider.
>>>
>>> Dave - WØLEV
>>>
>>> On Mon, Mar 22, 2021 at 2:28 AM Kim Elmore
><cw_de_n5op@sbcglobal.net> wrote:
>>>
>>> > It's odd that you can't hear it on your portable rx. That made me
>>> > curious: What if this is something internal to your '847? Have you
>
>>> > tried pulling your '847 and listening on a different receiver
>using
>>> > the same antenna? If you have, do you still hear the noise? It's a
>long shot, but...
>>> >
>>> > Kim N5OP
>>> >
>>> > On 3/21/2021 7:28 PM, Gary wrote:
>>> > > Mike,
>>> > >
>>> > > Thanks for the info. I understand locating the
>>> > > noise is
>>> > more important than identifying the noise. I am just try to play
>>> > all the angles as I was hoping to work the WPX contest nest
>>> > weekend. I have been walking the neighborhood a good chunk of the
>>> > afternoon, and have not been able to hear the noise on my portable
>
>>> > shortwave and loop antenna. It is as strong as ever on my home
>station.
>>> > >
>>> > > I have an MFJ 852 Noise Finder and it seems to
>>> > > go crazy
>>> > when broadside to any house. The neighbors on each side of me
>drive
>>> > the meter full scale.
>>> > >
>>> > > Yep I only want to knock on one door, as I know
>
>>> > > that
>>> > can get dicey. I would rather place a call to a utility, but can’t
>
>>> > really do either until I know.
>>> > >
>>> > > Keep the suggestions coming!
>>> > >
>>> > > Thanks and 73,
>>> > > Gary “Joe” kk0sd
>>> > >
>>> > > From: Mike Martin <mike@rfiservices.com>
>>> > > Sent: Sunday, March 21, 2021 6:53 PM
>>> > > To: Gary <gary_mayfield@hotmail.com>
>>> > > Cc: rfi@contesting.com
>>> > > Subject: Re: [RFI] New Interference at kk0sd
>>> > >
>>> > > Joe I haven't had time to read all the other input but I can
>tell
>>> > > you it
>>> > is not an arcing source or a sparking source. either one of the
>two
>>> > would be much broader than what you're reporting. if someone were
>>> > to tell you exactly what it is you really wouldn't be any further
>>> > ahead. You would still have to find which residents or business
>>> > it's in. My suggestion would be to either go mobile or on foot,
>>> > preferably on foot listening to the frequency that you know the
>>> > problem affects. once you locate the residents then go through the
>
>>> > breaker scenario and locate what the source is. Be 100% certain of
>
>>> > the structure or home that the problem is in before knocking on
>the
>>> > door. The last thing you want to do is start guessing. Guessing
>we'll ruin the relationship with your neighbors.
>>> > > Be safe,
>>> > > Mike k3RFI
>>> > > www.rfiservices.com<http://www.rfiservices.com>
>>> > > Get BlueMail for Android<http://www.bluemail.me/r?b=16696>
>>> > > On Mar 21, 2021, at 2:01 PM, Gary
><gary_mayfield@hotmail.com<mailto:
>>> > gary_mayfield@hotmail.com>> wrote:
>>> > >
>>> > > My last problem was tracked down to a neon sign in a neighbors
>>> > > garage. I
>>> > had several months of blissful relatively low noise operation, but
>
>>> > now have a new RFI issue.
>>> > >
>>> > > You can see a recording of it here:
>>> > > https://www.youtube.com/watch?v=GKf4P44FXMo
>>> > >
>>> > > I have turned all of the breakers in my home off and run the
>>> > > radio from
>>> > a battery and the noise remains.
>>> > >
>>> > > My neighborhood utilities are all underground.
>>> > >
>>> > > There are no solar installations in my neighborhood, and the
>>> > > noise is
>>> > there at night anyway...
>>> > >
>>> > > The noise is not detectable on the AM broadcast band, but starts
>
>>> > > around
>>> > 2 MHz and runs to at least 6 meters.
>>> > >
>>> > > It is there 7 days a week 24 hours a day.
>>> > >
>>> > > It is not detectable from my pickup when I drive the streets of
>>> > > my
>>> > neighborhood (checking both AM broadcast and Shortwave).
>>> > >
>>> > > If any one has heard something like this, I would love to hear
>>> > > what you
>>> > found.
>>> > >
>>> > > Thank You for your input and help!
>>> > >
>>> > > 73,
>>> > > Gary "Joe", kk0sd
>>> > >
>>> > >
>>> > > ________________________________
>>> > >
>>> > > RFI mailing list
>>> > > RFI@contesting.com<mailto:RFI@contesting.com>
>>> > > http://lists.contesting.com/mailman/listinfo/rfi
>>> > > _______________________________________________
>>> > > RFI mailing list
>>> > > RFI@contesting.com
>>> > > http://lists.contesting.com/mailman/listinfo/rfi
>>> > --
>>> >
>>> > Kim Elmore, Ph.D. (Adj. Assoc. Prof., OU School of Meteorology,
>>> > CCM, PP SEL/MEL/Glider, N5OP, 2nd Class Radiotelegraph, GROL)
>>> >
>>> > /"A great second violinist plays second fiddle to no one." //–
>Robert C.
>>> > Marsh, Chicago Sun-Times./
>>> >
>>> > _______________________________________________
>>> > RFI mailing list
>>> > RFI@contesting.com
>>> > http://lists.contesting.com/mailman/listinfo/rfi
>>> >
>>>
>>>
>>> --
>>> *Dave - WØLEV*
>>> *Just Let Darwin Work*
>>> _______________________________________________
>>> RFI mailing list
>>> RFI@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/rfi
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