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" <k...@comcast.net> > To: "Herbert Schoenbohm" <herbert.schoenb...@gmail.com> > Cc: "TopBand List" <email@example.com>, "kd9sv" <kd...@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.schoenb...@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 <kd...@comcast.net> wrote: >>> >>> Herb, FYI...gary, kd9sv >>> >>> -----Original Message----- >>> From: kd9sv [mailto:kd...@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-boun...@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 >>> >>> >>> --- >>> This email has been checked for viruses by AVG. >>> http://www.avg.com >>> >> _________________ >> Topband Reflector Archives - http://www.contesting.com/_topband > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > _________________ Topband Reflector Archives - http://www.contesting.com/_topband