Good point Frank,
We had similar problems at a Caribbean Island ham station and used a
pennant aimed at Europe with the back end pointed at the TX antenna about
100 meters away. Worked well that way. Their Beverage did not!
George, K8GG
> Hi Joel,
>
>
> In my opinion your elevated radials are a show stopper for an adjacent
> receiving antennas unless you can disconnect all of them when you're
> receiving.
>
>
> 73
> Frank
> W3LPL
>
> ----- Original Message -----
>
> From: "Joel" <k4wm@comcast.net>
> To: "Herbert Schoenbohm" <herbert.schoenbohm@gmail.com>
> Cc: "TopBand List" <topband@contesting.com>, "kd9sv" <kd9sv@comcast.net>
> Sent: Wednesday, March 7, 2018 12:48:57 AM
> Subject: Re: Topband: FW: Excessive noise on beverages
>
> Hi Gary
> Would you send the info you have re. tower detuning that you designed for
> K3UR. (Am using 1/4 wl tower with elevated radials)
> Thank you
> Joel
> k4wm
>
> Sent from my iPhone
>
>> On Mar 6, 2018, at 13:42, Herbert Schoenbohm
>> <herbert.schoenbohm@gmail.com> wrote:
>>
>> Great work Gary! This is probably a way that is much less expensive than
>> the commercial version of doing this.
>>
>> https://www.lbagroup.com/products/detunipole-detuning-skirt-kit
>>
>> Herb, KV4FZ
>>
>>> On Tue, Mar 6, 2018 at 2:28 PM, kd9sv <kd9sv@comcast.net> wrote:
>>>
>>> Herb, FYI...gary, kd9sv
>>>
>>> -----Original Message-----
>>> From: kd9sv [mailto:kd9sv@comcast.net]
>>> Sent: Tuesday, March 06, 2018 12:59 PM
>>> To: 'David Olean'
>>> Subject: RE: Topband: Excessive noise on beverages
>>>
>>> Dave, I have recently developed a simple "tower de-tuning system" that
>>> is
>>> in
>>> the "Beta Testing" phase. It will soon be available thru DXE as a
>>> system
>>> to
>>> de-tune a tower but I have no plans to use it on towers being used for
>>> transmitting, however; I did design a system for doing that which only
>>> requires adding one RJ1A or Kilovac HC1 type vacuum relay. I built one
>>> of
>>> those for K3UL which he has not yet installed. I will send you the
>>> drawing
>>> if I can find it on my computer. How are you feeding your tower? Gamma
>>> or
>>> what?
>>>
>>> 73, de gary, kd9sv
>>>
>>> -----Original Message-----
>>> From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of
>>> David
>>> Olean
>>> Sent: Tuesday, March 06, 2018 12:30 PM
>>> To: Topband Reflector
>>> Subject: Topband: Excessive noise on beverages
>>>
>>> I have been putzing around trying to improve my 160 meter setup, and
>>> have run into a real problem. Most of the USA is covered by two
>>> directions from here in Maine. SW and W. My problem is that I have an
>>> excessively high noise level on both of the beverages that run in these
>>> directions. In the last six months it has gotten worse, and so bad that
>>> I cannot use either beverage. The wires terminate at the side of my
>>> barn where I have ground rods and the RG-6 goes through PVC conduit up
>>> to the shack on the second floor of the barn. During the day I see
>>> noise levels at -133 or -132 on the two wires, but at night the noise
>>> had climbed to levels around -100 or to -110 on a good night. I
>>> suspected that I was getting noise coupled in from my vertical which is
>>> rather close and on the other side of my barn all of 55 ft away.
>>>
>>> Yesterday, I modified the west beverage and shortened it so that it
>>> terminated about 150 feet away from the barn and I ran new coax back
>>> across the field. I kept the SW beverage as is to compare noise levels
>>> at night. Lo and behold, but the noise went to -110 on the SW beverage,
>>> but only about -120 dBm on the modified beverage. This is a 10 dB
>>> improvement. Other directions at night run at about -130, so I am now
>>> seeing a 10 dB extra hit in noise to the west.
>>>
>>> The vertical is a shunt fed Rohn 25 with a total height just over 90 ft
>>> with top loading from a 5 element long boom 10 Meter yagi. I am not
>>> sure
>>> if it is possible to simply un resonate this tower. Does anyone have
>>> experience with simple ways to decouple a shunt fed tower from the rx
>>> antennas?
>>>
>>> The extra 10 dB of noise that I get to the west and SW is mostly due to
>>> the location of a town about 7 or 8 miles away in NH. It is ripe with
>>> all sorts of power line noise. I still can't rule out re radiation from
>>> the vertical though! I spent many years fighting with the electric
>>> utility to quell the noise. I involved Riley Hollingsworth and later
>>> on,
>>> Laura Smith, his replacement. The effort was futile and I lost heart as
>>> the problem was just too big for one person to fight. I was hoping that
>>> the noise would not affect 160 meters as it had messed up my VHF
>>> exploits, and so far I only have this ten dB swath of noise that
>>> bothers
>>> me in two directions.
>>>
>>> Any help with un resonating a shunt fed tower would be appreciated.
>>>
>>> Dave K1WHS
>>>
>>>
>>> _________________
>>> Topband Reflector Archives - http://www.contesting.com/_topband
>>>
>>>
>>> ---
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>>>
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