This post is the best evidence ever that "Top Posting" is a good Idea. Bill--W4BSG
----- Original Message ----- From: "gw3jxn" <[email protected]> To: <[email protected]> Sent: Sunday, May 06, 2012 3:27 AM Subject: Re: Topband: Topband Digest, Vol 113, Issue 8 > > ----- Original Message ----- > From: <[email protected]> > To: <[email protected]> > Sent: Saturday, May 05, 2012 7:00 PM > Subject: Topband Digest, Vol 113, Issue 8 > > >> Send Topband mailing list submissions to >> [email protected] >> >> To subscribe or unsubscribe via the World Wide Web, visit >> http://lists.contesting.com/mailman/listinfo/topband >> or, via email, send a message with subject or body 'help' to >> [email protected] >> >> You can reach the person managing the list at >> [email protected] >> >> When replying, please edit your Subject line so it is more specific >> than "Re: Contents of Topband digest..." >> >> >> Today's Topics: >> >> 1. Re: Fwd: radals fer 160m vertcal (Jim WA9YSD) >> 2. Re: Fwd: radals fer 160m vertcal (ZR) >> 3. Re: Fwd: radals fer 160m vertcal (Charlie Young) >> 4. Re: Fwd: radals fer 160m vertcal (Richard Fry) >> 5. Re: Fwd: radals fer 160m vertcal (James Rodenkirch) >> 6. Radials on top band (John Harden) >> 7. Re: Fwd: radals fer 160m vertcal (Mike Waters) >> >> >> ---------------------------------------------------------------------- >> >> Message: 1 >> Date: Sat, 5 May 2012 07:00:08 -0700 (PDT) >> From: Jim WA9YSD <[email protected]> >> Subject: Re: Topband: Fwd: radals fer 160m vertcal >> To: Top Band <[email protected]> >> Message-ID: >> <[email protected]> >> Content-Type: text/plain; charset=iso-8859-1 >> >> Keep in mind this Sole purpose of a BC station is to get coverage of >> about >> 60 miles running 5KW day time and 1 KW night time with no fad and quality >> signal not to work DX. >> >> I read in some posts or on some web site that it does not matter if the >> ends are tied to a ground rod or not.??Note then ends not at the base of >> the vertical. >> >> My backyard is only 35 by 36 feet.??You guys only think you have a small >> back yard.??Compare it with this one. >> >> The City water pipe system sure works as the good ground I guess so does >> the neighbors plumbing cause their house in only 8 feet from mine :-) >> >> Jim K9TF >> ? >> Stay on course, fight a good fight, and keep the faith.?Jim K9TF/WA9YSD >> >> ------------------------------ >> >> Message: 2 >> Date: Sat, 5 May 2012 10:34:06 -0400 >> From: "ZR" <[email protected]> >> Subject: Re: Topband: Fwd: radals fer 160m vertcal >> To: "Richard Fry" <[email protected]>, <[email protected]> >> Message-ID: <F637FEFE70F444C692A62D16142B015F@computer1> >> Content-Type: text/plain; format=flowed; charset="iso-8859-1"; >> reply-type=original >> >> There have been several reports of established AM stations that the FCC >> gave >> permission to replace a decayed or destroyed inground radial system with >> elevated radials or an elevated mesh/radial arrangement. >> >> In all the cases I read the FS measurements exceed the original and power >> had to be reduced to the original level. >> >> Carl >> KM1H >> >> >> ----- Original Message ----- >> From: "Richard Fry" <[email protected]> >> To: <[email protected]> >> Sent: Saturday, May 05, 2012 8:07 AM >> Subject: Re: Topband: Fwd: radals fer 160m vertcal >> >> >>> James Rodenkirch wrote: >>>>What about radials above the ground? >>> >>> This link http://www.commtechrf.com/documents/nab1995.pdf leads to a >>> paper >>> by Clarence Beverage with some real-world results for monopoles with >>> elevated wires used as a counterpoise. Here is a quote from it: >>> >>> >>> \ \The antenna system consisted of a lightweight, 15 inch face tower, >>> 120 >>> feet in height, with a base insulator at the 15 foot elevation and six >>> elevated radials, a quarter wave in length, spaced evenly around the >>> tower >>> and elevated 15 feet above the ground. The radials were fully insulated >>> from >>> ground and supported at the ends by wooden tripods. >>> >>> Power was fed to the system through a 200 foot length of coaxial cable >>> with >>> the cable shield connected to the shunt element of the T network and to >>> the >>> elevated radials. A balun or RF choke on the feedline was not employed >>> and >>> the feedline was isolated from the lower section of the tower. The >>> system >>> operated on 1580 kHz at a power of 750 watts. >>> >>> The efficiency of the antenna was determined by radial field intensity >>> measurements along 12 radials extending out to a distance of up to 85 >>> kilometers. The measured RMS efficiency was 287 mV/m for 1 kW, at one >>> kilometer, which is the same measured value as would be expected for a >>> 0.17 >>> wave tower above 120 buried radials. / / >>> >>> >>> So while such "elevated" installations are rare for AM broadcast >>> stations, >>> their performance has been measured to be about the same as when using >>> an >>> r-f ground consisting of 120 buried wires, each 1/4-wave long (free >>> space >>> length). >>> >>> These elevated systems are readily modeled using NEC-2. However the >>> radiation patterns shown by a typical NEC far-field analysis do not >>> accurately show the fields actually "launched" by them, or by any >>> vertical >>> radiator with its base near the earth, because they do not include the >>> surface wave. >>> >>> The fields radiated in and near the horizontal plane by any vertical >>> monopole of 5/8 wavelength height and less are the greatest fields it >>> radiates in the entire elevation plane, regardless of earth >>> conductivity. >>> Those fields from very low elevation angles (say, less then 5 degrees) >>> can >>> reach the ionosphere, and under the right conditions return to the earth >>> as >>> a useful skywave. >>> >>> The link below illustrates this concept. >>> >>> http://i62.photobucket.com/albums/h85/rfry-100/Space_Surface_Wave_Compare.gif >>> >>> >>> _______________________________________________ >>> UR RST IS ... ... ..9 QSB QSB - hw? BK >>> >>> >>> ----- >>> No virus found in this message. >>> Checked by AVG - www.avg.com >>> Version: 10.0.1424 / Virus Database: 2411/4978 - Release Date: 05/04/12 >>> >> >> >> >> ------------------------------ >> >> Message: 3 >> Date: Sat, 5 May 2012 09:50:31 -0500 >> From: Charlie Young <[email protected]> >> Subject: Re: Topband: Fwd: radals fer 160m vertcal >> To: <[email protected]>, <[email protected]> >> Message-ID: <[email protected]> >> Content-Type: text/plain; charset="iso-8859-1" >> >> >> Dick, thanks very much for posting the link for the Beverage elevated >> counterpoise article. Very interesting reading. >> >> Also thanks for the surface wave vs skywave graphic. >> >> >> 73 Chas N8RR >> >> >>> From: [email protected] >>> To: [email protected] >>> Date: Sat, 5 May 2012 07:07:11 -0500 >>> Subject: Re: Topband: Fwd: radals fer 160m vertcal >>> >>> James Rodenkirch wrote: >>> >What about radials above the ground? >>> >>> This link http://www.commtechrf.com/documents/nab1995.pdf leads to a >>> paper >>> by Clarence Beverage with some real-world results for monopoles with >>> elevated wires used as a counterpoise. Here is a quote from it: >>> >>> >>> \ \The antenna system consisted of a lightweight, 15 inch face tower, >>> 120 >>> feet in height, with a base insulator at the 15 foot elevation and six >>> elevated radials, a quarter wave in length, spaced evenly around the >>> tower >>> and elevated 15 feet above the ground. The radials were fully insulated >>> from >>> ground and supported at the ends by wooden tripods. >>> >>> Power was fed to the system through a 200 foot length of coaxial cable >>> with >>> the cable shield connected to the shunt element of the T network and to >>> the >>> elevated radials. A balun or RF choke on the feedline was not employed >>> and >>> the feedline was isolated from the lower section of the tower. The >>> system >>> operated on 1580 kHz at a power of 750 watts. >>> >>> The efficiency of the antenna was determined by radial field intensity >>> measurements along 12 radials extending out to a distance of up to 85 >>> kilometers. The measured RMS efficiency was 287 mV/m for 1 kW, at one >>> kilometer, which is the same measured value as would be expected for a >>> 0.17 >>> wave tower above 120 buried radials. / / >>> >>> >>> So while such "elevated" installations are rare for AM broadcast >>> stations, >>> their performance has been measured to be about the same as when using >>> an >>> r-f ground consisting of 120 buried wires, each 1/4-wave long (free >>> space >>> length). >>> >>> These elevated systems are readily modeled using NEC-2. However the >>> radiation patterns shown by a typical NEC far-field analysis do not >>> accurately show the fields actually "launched" by them, or by any >>> vertical >>> radiator with its base near the earth, because they do not include the >>> surface wave. >>> >>> The fields radiated in and near the horizontal plane by any vertical >>> monopole of 5/8 wavelength height and less are the greatest fields it >>> radiates in the entire elevation plane, regardless of earth >>> conductivity. >>> Those fields from very low elevation angles (say, less then 5 degrees) >>> can >>> reach the ionosphere, and under the right conditions return to the earth >>> as >>> a useful skywave. >>> >>> The link below illustrates this concept. >>> >>> http://i62.photobucket.com/albums/h85/rfry-100/Space_Surface_Wave_Compare.gif >>> >>> >>> _______________________________________________ >>> UR RST IS ... ... ..9 QSB QSB - hw? BK >> >> >> ------------------------------ >> >> Message: 4 >> Date: Sat, 5 May 2012 09:57:53 -0500 >> From: "Richard Fry" <[email protected]> >> Subject: Re: Topband: Fwd: radals fer 160m vertcal >> To: "ZR" <[email protected]>, <[email protected]> >> Message-ID: <48160BBF32D34941B2939C7D44EEC6C4@ToshLaptop> >> Content-Type: text/plain; format=flowed; charset="iso-8859-1"; >> reply-type=response >> >> Carl KM1H wrote: >>> There have been several reports of established AM stations that the FCC >>> gave permission to replace a decayed or destroyed inground radial system >>> with elevated radials or an elevated mesh/radial arrangement. >>> >>> In all the cases I read the FS measurements exceed the original and >>> power >>> had to be reduced to the original level. >> >> The FCC requires minimum "efficiencies" for the radiators of various >> classes >> of licensed AM broadcast stations, expressed as the r.m.s. field >> intensity >> of the ground wave produced at 1 km for 1 kW of power applied to the >> antenna >> system. The FCC doesn't have an upper limit for AM broadcast field >> intensities except when a directional radiation pattern is required. >> >> For an example of the non-directional case, there are stations licensed >> for >> 1 kW on 1400 kHz that use 1/2-wave monopoles instead of 1/4-wave (or >> shorter) monopoles. Such stations using 1/2-wave monopoles still use 1 >> kW >> transmitters, produce higher fields at all distances, and have larger >> useful >> groundwave coverage areas than those using 1/4-wave and shorter >> monopoles. >> This is all perfectly legal. >> >> >> >> ------------------------------ >> >> Message: 5 >> Date: Sat, 5 May 2012 09:12:18 -0600 >> From: James Rodenkirch <[email protected]> >> Subject: Re: Topband: Fwd: radals fer 160m vertcal >> To: <[email protected]>, <[email protected]> >> Message-ID: <[email protected]> >> Content-Type: text/plain; charset="iso-8859-1" >> >> >> Thank you, Richard, fore passing the paper on....looks like I won't >> "suffer" by having elevated radials in the least. Jim R. K9JWV >> >> >> >> > From: [email protected] >>> To: [email protected] >>> Date: Sat, 5 May 2012 07:07:11 -0500 >>> Subject: Re: Topband: Fwd: radals fer 160m vertcal >>> >>> James Rodenkirch wrote: >>> >What about radials above the ground? >>> >>> This link http://www.commtechrf.com/documents/nab1995.pdf leads to a >>> paper >>> by Clarence Beverage with some real-world results for monopoles with >>> elevated wires used as a counterpoise. Here is a quote from it: >>> >>> >>> \ \The antenna system consisted of a lightweight, 15 inch face tower, >>> 120 >>> feet in height, with a base insulator at the 15 foot elevation and six >>> elevated radials, a quarter wave in length, spaced evenly around the >>> tower >>> and elevated 15 feet above the ground. The radials were fully insulated >>> from >>> ground and supported at the ends by wooden tripods. >>> >>> Power was fed to the system through a 200 foot length of coaxial cable >>> with >>> the cable shield connected to the shunt element of the T network and to >>> the >>> elevated radials. A balun or RF choke on the feedline was not employed >>> and >>> the feedline was isolated from the lower section of the tower. The >>> system >>> operated on 1580 kHz at a power of 750 watts. >>> >>> The efficiency of the antenna was determined by radial field intensity >>> measurements along 12 radials extending out to a distance of up to 85 >>> kilometers. The measured RMS efficiency was 287 mV/m for 1 kW, at one >>> kilometer, which is the same measured value as would be expected for a >>> 0.17 >>> wave tower above 120 buried radials. / / >>> >>> >>> So while such "elevated" installations are rare for AM broadcast >>> stations, >>> their performance has been measured to be about the same as when using >>> an >>> r-f ground consisting of 120 buried wires, each 1/4-wave long (free >>> space >>> length). >>> >>> These elevated systems are readily modeled using NEC-2. However the >>> radiation patterns shown by a typical NEC far-field analysis do not >>> accurately show the fields actually "launched" by them, or by any >>> vertical >>> radiator with its base near the earth, because they do not include the >>> surface wave. >>> >>> The fields radiated in and near the horizontal plane by any vertical >>> monopole of 5/8 wavelength height and less are the greatest fields it >>> radiates in the entire elevation plane, regardless of earth >>> conductivity. >>> Those fields from very low elevation angles (say, less then 5 degrees) >>> can >>> reach the ionosphere, and under the right conditions return to the earth >>> as >>> a useful skywave. >>> >>> The link below illustrates this concept. >>> >>> http://i62.photobucket.com/albums/h85/rfry-100/Space_Surface_Wave_Compare.gif >>> >>> >>> _______________________________________________ >>> UR RST IS ... ... ..9 QSB QSB - hw? BK >> >> >> ------------------------------ >> >> Message: 6 >> Date: Sat, 05 May 2012 13:02:26 -0400 >> From: John Harden <[email protected]> >> Subject: Topband: Radials on top band >> To: [email protected] >> Message-ID: <[email protected]> >> Content-Type: text/plain; charset=ISO-8859-1; format=flowed >> >> I can work anything I can hear on 160. That's the whole deal... If I >> can't hear it on the Hi-Z 4-square I can't work it...... >> >> I have a 45G 100 foot tower shunt fed with an Omega match of vacuum >> variables. I am always flat as the variable to ground is motor driven. I >> have 32 radials..... At this point the curve starts to become >> asymptotic. But, I still plan to add 32 more before the next top band >> season.... >> >> I've really enjoyed hearing all of the theory. It is in the books...all >> of it... >> >> I have one book here entitled "Electromagnetics" by the late John Krause >> (W8JK, SK) of the EE department of Ohio State Univ. The book has all of >> the theory (if you can do calculus and differential equations) to >> substantiate the fact that 120 radials is optimal.... He goes way beyond >> opinions and assertions. All of his statements are guided by double >> blind scientific studies.. >> >> I had a quiz question at GA Tech eons ago. The question was "why is the >> sky blue"? You couldn't BS those guys there. It took 5 pages of calculus >> to answer it... It had to do with electrons going from one energy level >> to another.... >> >> Go get 'em on top band.. >> >> 73, >> >> John, W4NU >> K4JAG (1959 to 1998) >> >> >> >> >> ------------------------------ >> >> Message: 7 >> Date: Sat, 5 May 2012 13:33:35 -0500 >> From: Mike Waters <[email protected]> >> Subject: Re: Topband: Fwd: radals fer 160m vertcal >> To: topband <[email protected]> >> Message-ID: >> <ca+fxyxicetxoohvbnlm__5vdkcakeferr74v1542l5ztxkv...@mail.gmail.com> >> Content-Type: text/plain; charset=ISO-8859-1 >> >> Thanks for the wisdom, Rich. :-) >> >> However, I've always wondered about the following statement. My question >> is, on what amateur bands is this common? And on what amateur bands is >> this >> possible? >> >> On Sat, May 5, 2012 at 7:07 AM, Richard Fry <[email protected]> wrote: >> >>> Those fields from very low elevation angles (say, less then 5 degrees) >>> can >>> reach the ionosphere, and under the right conditions return to the earth >>> as >>> a useful skywave. >>> >> >> 73, Mike >> www.w0btu.com >> >> >> ------------------------------ >> >> _______________________________________________ >> Topband mailing list >> [email protected] >> http://lists.contesting.com/mailman/listinfo/topband >> >> >> End of Topband Digest, Vol 113, Issue 8 >> *************************************** > > _______________________________________________ > UR RST IS ... ... ..9 QSB QSB - hw? BK > _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
