Topband: RF ground radials
KB8NTY
kb8nty at wowway.com
Fri Feb 14 13:18:43 EST 2014
In reference to all the ground radial postings;
A link to a source of RF ground radial links, all in one place without
having to search the web, links are always updated.
-73-
http://www.rossradio.net/
+++++++++++++++++++++++++++++++++++++++++++++++++++++
> Today's Topics:
>
> 1. Re: TO7CC (Ray Benny)
> 2. Ice (Tom W8JI)
> 3. Re: Ice (Mike Waters)
> 4. Re: Ice (Charlie Cunningham)
> 5. Re: Power stayed on! (Gary Smith)
> 6. Re: NQ4I (Mike Waters)
> 7. Re: Power stayed on! (ZR)
> 8. Question - optimum number of radials (DALE LONG)
> 9. Re: Question - optimum number of radials (Mike Waters)
> 10. Re: Question - optimum number of radials (Joe Subich, W4TV)
> 11. Re: Ice (n0tt1 at juno.com)
> 12. Re: Ice (Gary and Kathleen Pearse)
> 13. Re: Question - optimum number of radials (Tom W8JI)
> 14. Re: Question - optimum number of radials (Brad Rehm)
> 15. Re: Question - optimum number of radials (Tom W8JI)
> 16. Re: Question - optimum number of radials (Dan Maguire)
> 17. Palomar R-X Noise Bridge (mapa50 at windstream.net)
> 18. Re: Question - optimum number of radials (Richard Fry)
> 19. Re: Question - optimum number of radials (Charlie Cunningham)
> 20. Re: Question - optimum number of radials (Bill Cromwell)
> 21. Question - optimum number of radials (James Rodenkirch)
> 22. Re: Question - optimum number of radials (Carl)
> 23. Re: Palomar R-X Noise Bridge (Carl)
> 24. Re: Question - optimum number of radials (Charlie Cunningham)
> 25. Re: Question - optimum number of radials (Charlie Cunningham)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Thu, 13 Feb 2014 12:35:12 -0700
> From: Ray Benny <rayn6vr at cableone.net>
> Cc: "topband at contesting.com" <topband at contesting.com>, f6ira at sfr.fr
> Subject: Re: Topband: TO7CC
> Message-ID:
> <CAC716YZb4xTKXcygPJcz2afMom=Dt-B-2BPLzkpHO-pe7V_4Uw at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Heard TO7CC at our SS yesterday on 80m CW - 0100z, until about 0130z. You
> worked K6XT, but I was there too.
>
> Will be looking for you on 80m CW at or Sunset this evening, about 0100z
> and later.
>
> 73, & tnx,
>
> Ray,
> N6VR
>
>
> On Thu, Feb 13, 2014 at 7:35 AM, Doug Renwick <ve5ra at sasktel.net> wrote:
>
>> I haven't heard them or seen spots on 160 or 80 for the west coast around
>> 1400 UTC give or take.
>> Doug
>>
>> -----Original Message-----
>>
>> Try to focuse our work on top band each time as possible. Every nights
>> ops
>> are there. At the end of FT5ZM QRG back quiet but dont Forget that
>> another
>> guys still on fr?quences for you. Finaly team stay on the Island untill
>> sunday morning. D?pending cndx Est coast stations Can be ear half and
>> more
>> after SR. In FR time around 2H30 AM. Last night have strong noise even
>> on
>> 80 didn't log much qso in lows bands.
>>
>> TO7CC team
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
>>
>> ---
>> This email is free from viruses and malware because avast! Antivirus
>> protection is active.
>> http://www.avast.com
>>
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
>
>
> ------------------------------
>
> Message: 2
> Date: Thu, 13 Feb 2014 15:32:53 -0500
> From: "Tom W8JI" <w8ji at w8ji.com>
> To: <topband at contesting.com>
> Subject: Topband: Ice
> Message-ID: <EE168A8969984EEAB34FD00755CF9ABD at MAIN>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
> The ice that fell off my Yagi's typically measures about 1" thick off the
> largest pieces, and 1/2" thick on the smaller thicknesses. I'm going to
> assume the thick pieces are from the bottoms, so that's probably like 3/4
> inch radial ice.
>
> We lost power just before sunset last night.The power lines are a mess on
> my
> road, I'd guess they use maybe 400 ft spans, so they broke in multiple
> places. I expect days before we have commercial power.
>
> All of my Yagis sprung back except the 40 meter antenna. The ice dropped
> off
> one side of the top antenna, so it rotated the elements enough to look
> pretty ugly. The bottom 40M Yagi lived just fine until big chunks of ice
> kept banging it, and then one side of one element bent.
>
> Many ropes snapped. The next time I need to remember to go out and release
> tension **before** the ice hits. Once it started icing, none of the ropes
> running through pulleys could be released.
>
> I have not looked at Beverages and in woods and fields, but I have a lot
> of
> tree and building damage so I expect some chain saw and receiving antenna
> work.
>
> All in all not bad for such a large amount of ice.
>
> 73 Tom
>
>
>
> ------------------------------
>
> Message: 3
> Date: Thu, 13 Feb 2014 14:47:50 -0600
> From: Mike Waters <mikewate at gmail.com>
> To: topband <topband at contesting.com>
> Subject: Re: Topband: Ice
> Message-ID:
> <CA+FxYXiHU-Ca4h2vmTPWna0eAEeJEe4nZiYigFHs0vHcN6pSxQ at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> The last ice storm surely would have taken down my 160m inverted-L, had it
> not been for the counterweight at the end. (It's made from #16 THHN, not
> very strong.) The pulley did not completely ice up, apparently because it
> moved every so often as ice made the antenna heavier.
>
> At one point, the ice on the antenna raised the counterweight way up in
> the
> air. After the ice melted, it all returned to the way it was before the
> storm.
>
> I lost one wire on one of the Beverages (where there was a kink from other
> damage), but it's a matter of time before a bigger ice storm completely
> takes down both Beverages. I'm toying with the idea of counterweights at
> the ends to help protect them. The pulleys are already there.
>
> 73, Mike
> www.w0btu.com
>
> On Thu, Feb 13, 2014 at 2:32 PM, Tom W8JI <w8ji at w8ji.com> wrote:
>
>> Many ropes snapped. The next time I need to remember to go out and
>> release
>> tension **before** the ice hits. Once it started icing, none of the ropes
>> running through pulleys could be released.
>>
>
>
> ------------------------------
>
> Message: 4
> Date: Thu, 13 Feb 2014 15:56:23 -0500
> From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
> To: "'Tom W8JI'" <w8ji at w8ji.com>
> Cc: topband at contesting.com
> Subject: Re: Topband: Ice
> Message-ID:
> <!&!AAAAAAAAAAAYAAAAAAAAAF0xXac1rOhFkn7GlcEWNIjCgAAAEAAAABcLdiBM4ctDvrhTb4MHLlgBAAAAAA==@nc.rr.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> Yikes!!
>
> BTW - that lower 40m yagi with the bent element probably works just fine!
> I
> don't know if you've ever modeled yagis with bent or missing elements,
> but
> the results are pretty interesting! Yagis just "want to work"! :-)
>
> GL!
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Tom
> W8JI
> Sent: Thursday, February 13, 2014 3:33 PM
> To: topband at contesting.com
> Subject: Topband: Ice
>
> The ice that fell off my Yagi's typically measures about 1" thick off the
> largest pieces, and 1/2" thick on the smaller thicknesses. I'm going to
> assume the thick pieces are from the bottoms, so that's probably like 3/4
> inch radial ice.
>
> We lost power just before sunset last night.The power lines are a mess on
> my
> road, I'd guess they use maybe 400 ft spans, so they broke in multiple
> places. I expect days before we have commercial power.
>
> All of my Yagis sprung back except the 40 meter antenna. The ice dropped
> off
> one side of the top antenna, so it rotated the elements enough to look
> pretty ugly. The bottom 40M Yagi lived just fine until big chunks of ice
> kept banging it, and then one side of one element bent.
>
> Many ropes snapped. The next time I need to remember to go out and release
> tension **before** the ice hits. Once it started icing, none of the ropes
> running through pulleys could be released.
>
> I have not looked at Beverages and in woods and fields, but I have a lot
> of
> tree and building damage so I expect some chain saw and receiving antenna
> work.
>
> All in all not bad for such a large amount of ice.
>
> 73 Tom
>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 5
> Date: Thu, 13 Feb 2014 17:31:12 -0500
> From: "Gary Smith" <Gary at ka1j.com>
> To: Topband at contesting.com
> Subject: Re: Topband: Power stayed on!
> Message-ID: <52FD47B0.21094.1E33A4C5 at Gary.ka1j.com>
> Content-Type: text/plain; charset=US-ASCII
>
>
> Genuinely sorry to hear of the unfortunate damage this storm has done
> to some of us. It takes so much effort to put things together in a
> way that we're happy with and mother nature can undo it in a
> heartbeat. Sandy did my damage with salt water submerging all my
> external antenna switching systems as well as the loss of my wire
> antennas which snapped from falling branches. This time I escaped
> damage, I hope those affected get their equipment back to shape as
> fast as possible.
>
> 73,
>
> Gary
> KA1J
>
>
> ---
> This email is free from viruses and malware because avast! Antivirus
> protection is active.
> http://www.avast.com
>
>
>
> ------------------------------
>
> Message: 6
> Date: Thu, 13 Feb 2014 16:38:38 -0600
> From: Mike Waters <mikewate at gmail.com>
> To: "John Harden, D.M.D." <jhdmd at bellsouth.net>, topband
> <topband at contesting.com>
> Subject: Re: Topband: NQ4I
> Message-ID:
> <CA+FxYXgC=ApjFEDmbqztKQpELGgGtsGQg8dw2tjSa9Mcx2TkAw at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Need heaters inside the elements, at least towards the ends, that can be
> turned on to melt the ice.
>
> Where there's a will, there's a way to do that.
>
> 73, Mike
> www.w0btu.com
>
>
> On Thu, Feb 13, 2014 at 2:51 PM, John Harden, D.M.D.
> <jhdmd at bellsouth.net>wrote:
>
>> Hi all...well the antennas are starting to give up...so far I have
>>> lost the top 40m KLM 4 el at 155 ft that is used for the MULT
>>> station...it is dangling from the top of the tower..next to go will be
>>> the 3 el Telrex 40m RUN top antenna...also ready to fold up is the
>>> monster 8 el homebrew 8 el 20m on 89 ft boom...not looking good either
>>> is the top 8 el 15m RUN antenna at 155 ft...I might very well lose the
>>> rest of the antennas tonight...it is raining and ice pellets and the
>>> loads keep increasing on the antennas...we had planed to operate in
>>> the ARRL CW this coming weekend...not sure if there will be any
>>> antennas left...tomorrow morning will end the storm around 11
>>> am..temps are forecast to rise to 34 degrees F and maybe some melting
>>> will tke place.
>>>
>>> de Rick NQ4I
>>>
>>
>
>
> ------------------------------
>
> Message: 7
> Date: Thu, 13 Feb 2014 17:48:33 -0500
> From: "ZR" <zr at jeremy.mv.com>
> To: <Gary at ka1j.com>, <Topband at contesting.com>
> Subject: Re: Topband: Power stayed on!
> Message-ID: <225E5B1916F14A4FA76F76D75928864A at computer1>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
> Looks like we dodged the bullet here also. Storms are unpredictable and go
> anywhere from right up the Hudson River valley to out to sea
>
> Watching the storm track it took a sharp right turn over LI, NY and then a
> NE tack past Boston and out to sea.
>
> About 8" of fluff which stopped about 4PM and likely some rain later
> tonight
> from the back side as the temps get into the 40's. We are still getting a
> few 25-30 mph gusts but not like earlier when it was pretty steady for
> several hours.
>
> I took one pass with the plowtruck at 430 so we can get in/out as needed
> and
> will do the cleanup tomorrow.
>
> Carl
> KM1H
>
>
> Subject: Re: Topband: Power stayed on!
>
>
>>
>> Genuinely sorry to hear of the unfortunate damage this storm has done
>> to some of us. It takes so much effort to put things together in a
>> way that we're happy with and mother nature can undo it in a
>> heartbeat. Sandy did my damage with salt water submerging all my
>> external antenna switching systems as well as the loss of my wire
>> antennas which snapped from falling branches. This time I escaped
>> damage, I hope those affected get their equipment back to shape as
>> fast as possible.
>>
>> 73,
>>
>> Gary
>> KA1J
>>
>>
>> ---
>> This email is free from viruses and malware because avast! Antivirus
>> protection is active.
>> http://www.avast.com
>>
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 8
> Date: Thu, 13 Feb 2014 15:12:42 -0800 (PST)
> From: DALE LONG <dale.long at prodigy.net>
> To: "topband at contesting.com" <topband at contesting.com>
> Subject: Topband: Question - optimum number of radials
> Message-ID:
> <1392333162.70654.YahooMailNeo at web184303.mail.ne1.yahoo.com>
> Content-Type: text/plain; charset=iso-8859-1
>
> I understand that 120 radials is the golden standard. ?At what point is
> there no significant improvement?
>
> How much worse is 60 radials? ?How much worse is 24 radials (4 of 1/4
> lambda and 20 or 1/10 lambda)?
>
> This may have been discussed in the past, but if there is any engineering
> reference or field testing that has been done, I would like to know the
> results.
>
> Thanks
>
> Dale - N3BNA
>
> ------------------------------
>
> Message: 9
> Date: Thu, 13 Feb 2014 17:18:14 -0600
> From: Mike Waters <mikewate at gmail.com>
> To: topband <topband at contesting.com>
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID:
> <CA+FxYXjgwWkbCmwTmpdR_K3q9Baw1Azdq08E7SmyO2zTv+QcGw at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> w0btu.com/Optimum_number_of_ground_radials_vs_radial_length.html
>
> Check the links on that page to N6LF, Rudy Severns' pages. His work has
> been called the gold standard of radial science.
>
> 73, Mike
> www.w0btu.com
>
>
> On Thu, Feb 13, 2014 at 5:12 PM, DALE LONG <dale.long at prodigy.net> wrote:
>
>> I understand that 120 radials is the golden standard. At what point is
>> there no significant improvement?
>>
>> How much worse is 60 radials? How much worse is 24 radials (4 of 1/4
>> lambda and 20 or 1/10 lambda)?
>>
>
>
> ------------------------------
>
> Message: 10
> Date: Thu, 13 Feb 2014 18:26:14 -0500
> From: "Joe Subich, W4TV" <lists at subich.com>
> To: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID: <52FD5496.7050700 at subich.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>
> N6LF has done quite a bit of actual testing of various in ground and
> elevated radial systems. See: http://www.antennasbyn6lf.com/
>
> K3LC has done extensive modeling of both in ground and elevated
> radial systems: http://www2.gcc.edu/dept/elee/Faculty/Christman.htm
>
> However, if the majority of your on/in ground radials are only 0.1 wave
> you won't need many before the point of diminishing returns.
>
>
> 73,
>
> ... Joe, W4TV
>
>
> On 2/13/2014 6:12 PM, DALE LONG wrote:
>> I understand that 120 radials is the golden standard. At what point is
>> there no significant improvement?
>>
>> How much worse is 60 radials? How much worse is 24 radials (4 of 1/4
>> lambda and 20 or 1/10 lambda)?
>>
>> This may have been discussed in the past, but if there is any engineering
>> reference or field testing that has been done, I would like to know the
>> results.
>>
>> Thanks
>>
>> Dale - N3BNA
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
>
>
> ------------------------------
>
> Message: 11
> Date: Thu, 13 Feb 2014 23:54:38 +0000
> From: <n0tt1 at juno.com>
> To: mikewate at gmail.com,topband at contesting.com
> Subject: Re: Topband: Ice
> Message-ID: <AABKR4ZYRAXE9PR2 at smtpout01.vgs.untd.com>
> Content-Type: text/plain; charset=us-ascii
>
>> I lost one wire on one of the Beverages (where there was a kink from
>> other
>> damage), but it's a matter of time before a bigger ice storm
>> completely
>> takes down both Beverages. I'm toying with the idea of
>> counterweights at
>> the ends to help protect them. The pulleys are already there.
>>
>> 73, Mike
>> www.w0btu.com
>
> FWIW, I rigged all my PVC Beverage poles so they are
> simply zip-tied to metal T-posts. When an ice storm
> is predicted, all that needs to be done is to clip the
> ties and let the poles/wire fall to the ground. It takes
> about 1/2 hour (if even that) to set them upright after the storm.
>
> 73,
> Charlie, N0TT
>
>
>
> ------------------------------
>
> Message: 12
> Date: Thu, 13 Feb 2014 16:47:32 -0900
> From: Gary and Kathleen Pearse <pearse at gci.net>
> To: topband List <topband at contesting.com>
> Subject: Re: Topband: Ice
> Message-ID: <2E02DF8A-4B32-4F29-B746-330687DA16B6 at gci.net>
> Content-Type: text/plain; charset=windows-1252
>
> I believe OH8X had one or more ?hammers? mounted to their 160 Yagi to help
> remove the ice buildup. Sadly their extraordinary effort recently fell
> victim to winds and reportedly torque:
> http://dx-world.net/2013/oh8x-tower-collapse/
>
> Not sure what the answer is. My Puny 3-el SteppIR with fiberglass elements
> and retracted innards survived a November ice storm, gusts 60-70 reported
> locally, and a direct hit to the director by a falling tree and the 160
> Inv-L wire. One bracket is bent some, the boom is bent some, but it still
> works. Repairs when it?s warmer.
>
> Take care, there?s more on the way as far as Lower 48?s stormy WX:
>
> http://www.weatherstreet.com/states/gfsx-sfc-temperature-and-wind-forecast.htm
> http://www.weatherstreet.com/states/gfsx-slp-forecast.htm
>
> 73, Gary NL7Y
>
>
>
>
> ------------------------------
>
> Message: 13
> Date: Thu, 13 Feb 2014 20:49:47 -0500
> From: "Tom W8JI" <w8ji at w8ji.com>
> To: "DALE LONG" <dale.long at prodigy.net>, <topband at contesting.com>
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID: <84F3D7BE677E47A2B53E9FCB1780E6F2 at MAIN>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
>
>
> I understand that 120 radials is the golden standard. At what point is
> there
> no significant improvement?>>>
>
> 120 radials never was a gold standard.
>
> The FCC said if a AM BC station uses something like 110 radials, I forget
> the exact number, they can avoid doing a radial system proof of
> performance.
> I think Hams assumed that somehow meant 110 radials or whatever the exact
> number was were somehow "perfect".
>
> There is no improvement here on 40M at about 20-30 radials. YMMV.
>
> This will be different on different bands at the same location, and
> different on the same bands at different locations, and even different
> with
> different antennas. So what happens in one cause is probably not true in
> others.
>
> Read carefully, and you will see even Rudy Severns says that, so his gold
> standard isn't gold.
>
> 73 Tom
>
>
>
> ------------------------------
>
> Message: 14
> Date: Thu, 13 Feb 2014 20:11:26 -0600
> From: Brad Rehm <bradrehm at gmail.com>
> To: Tom W8JI <w8ji at w8ji.com>
> Cc: DALE LONG <dale.long at prodigy.net>, "topband at contesting.com"
> <topband at contesting.com>
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID:
> <CABBfdyTt1es+L42hZ8FtBAunqd7Aiu-Lz3xK0z_nJP6cJ9E3Aw at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Jerry Sevick, W2FMI, has an interesting comment about the "120" number in
> his book, "The Short Vertical Antenna and Ground Radial." At the end of
> the first chapter he notes:
>
> "...it should be mentioned that the world standard for the number of
> radials to be used with verticals in the AM broadcast band is 120. This
> number was based on the classic paper published in 1937 by Brown, Lewis,
> and Epstein. During the course of a business meeting with Dr. Brown, I
> asked him how he and his colleagues arrived at the 120 radial
> figure--because I was quite sure 100 would work as well. His answer was
> interesting.
>
> "He said that he and the others had been thinking in terms of 100 radials,
> but the farmer who plowed in 100 radials had wire left over because copper
> is soft and stretches easily. When he asked what to do with the extra
> wire, the farmer was told to plow it in. The result was a world standard
> of 120 radials."
>
> Hmmmm!
>
> Brad, KV5V
>
>
> On Thu, Feb 13, 2014 at 7:49 PM, Tom W8JI <w8ji at w8ji.com> wrote:
>
>>
>>
>> I understand that 120 radials is the golden standard. At what point is
>> there no significant improvement?>>>
>>
>> 120 radials never was a gold standard.
>>
>> The FCC said if a AM BC station uses something like 110 radials, I forget
>> the exact number, they can avoid doing a radial system proof of
>> performance. I think Hams assumed that somehow meant 110 radials or
>> whatever the exact number was were somehow "perfect".
>>
>> There is no improvement here on 40M at about 20-30 radials. YMMV.
>>
>> This will be different on different bands at the same location, and
>> different on the same bands at different locations, and even different
>> with
>> different antennas. So what happens in one cause is probably not true in
>> others.
>>
>> Read carefully, and you will see even Rudy Severns says that, so his gold
>> standard isn't gold.
>>
>> 73 Tom
>>
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
>
>
> ------------------------------
>
> Message: 15
> Date: Thu, 13 Feb 2014 22:39:11 -0500
> From: "Tom W8JI" <w8ji at w8ji.com>
> To: "Brad Rehm" <bradrehm at gmail.com>
> Cc: DALE LONG <dale.long at prodigy.net>, topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID: <DF7DD3536C7E4377BD095F7CFCBEE760 at MAIN>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
>> Jerry Sevick, W2FMI, has an interesting comment about the "120" number in
>> his book, "The Short Vertical Antenna and Ground Radial." At the end of
>> the first chapter he notes:
>>
>> "...it should be mentioned that the world standard for the number of
>> radials to be used with verticals in the AM broadcast band is 120. This
>> number was based on the classic paper published in 1937 by Brown, Lewis,
>> and Epstein. During the course of a business meeting with Dr. Brown, I
>> asked him how he and his colleagues arrived at the 120 radial
>> figure--because I was quite sure 100 would work as well. His answer was
>> interesting.
>>
>> "He said that he and the others had been thinking in terms of 100
>> radials,
>> but the farmer who plowed in 100 radials had wire left over because
>> copper
>> is soft and stretches easily. When he asked what to do with the extra
>> wire, the farmer was told to plow it in. The result was a world standard
>> of 120 radials."
>
> That's an interesting story, but the story-teller must never have looked
> at
> the papers.
> BL and E used 113 radials maxium, not 120.
>
> Brown, Lewis, and Epstein's papers are all over the web, if you search for
> them.
>
> The FCC says:
>
> "At the present development of the art, it is considered that where a
> vertical radiator is employed with its base on the ground, the ground
> system
> should consist of buried radial wires at least one-fourth wave length
> long.
> There should be as many of these radials evenly spaced as practicable and
> in
> no event less than 90. (120 radials of 0.35 to 0.4 of a wave length in
> length and spaced 3? is considered an excellent ground system and in case
> of
> high base voltage, a base screen of suitable dimensions should be
> employed.)"
>
> So you see, the FCC requires 90 radials unless you prove you can make
> efficiency with fewer. They do not say 120 quarter wave radials, they
> require 90 1/4 wave or longer, and say 120 radials .35 to .4 wl is
> "considered excellent".
>
>
>
>
>
>
> ------------------------------
>
> Message: 16
> Date: Thu, 13 Feb 2014 20:18:13 -0800 (PST)
> From: Dan Maguire <djm2150 at yahoo.com>
> To: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID:
> <1392351493.14884.YahooMailBasic at web122606.mail.ne1.yahoo.com>
> Content-Type: text/plain; charset=us-ascii
>
> For anyone interested in modeling a vertical with a variable number of
> radials you might refer back to this post:
>
> http://lists.contesting.com/archives//html/Topband/2013-04/msg00017.html
>
> Near the bottom you'll find a link to download a ".weq" format model for
> use with AutoEZ. AutoEZ requires Microsoft Excel and EZNEC v5.
>
> (Shooting myself in the foot here.) Even using the free demo version of
> AutoEZ you can still take advantage of the "multi-config" aspect of the
> model. Manually set the variables to any desired values (such as variable
> "N" for number of radials) then use the "View Ant" button. That will
> build a temporary .ez format model and send it to EZNEC. Then switch over
> to the EZNEC main window and click the EZNEC "FF Plot" button or other
> buttons as desired. In effect you are using AutoEZ to build the model and
> EZNEC to process it.
>
> If you don't have the Pro/4 (NEC-4) version of EZNEC you can simulate
> buried radials by putting them ~0.001 wavelengths above ground. For info
> on that subject see the EZNEC Help Index > Elevated Radial Systems.
>
> Dan, AC6LA
> http://ac6la.com
>
>
> ------------------------------
>
> Message: 17
> Date: Thu, 13 Feb 2014 23:18:07 -0600
> From: <mapa50 at windstream.net>
> To: topband at contesting.com
> Subject: Topband: Palomar R-X Noise Bridge
> Message-ID: <20140214001807.3QQMJ.853.root at pamxwww05-z01>
> Content-Type: text/plain; charset=utf-8
>
> I have a question about using the noise bridge. I have used it cut stubs
> to 1/4 wavelength using 52 ohm cable with no problems. I now need some
> stubs using 75 ohm cable which I have on hand.
>
> Will the same procedure work for 75 ohm that works for 52 ohm cable, or
> will the different impedance need to be accounted for. I started to cut
> cable and this question came to me. My first thought is that it will work
> fine, but I am not sure. I did some searches on the web but found nothing
> about it. Any help would be appreciated.
>
> Thanks, Pat Armstrong
> KF5YZ
>
>
> ------------------------------
>
> Message: 18
> Date: Fri, 14 Feb 2014 06:00:00 -0600
> From: "Richard Fry" <rfry at adams.net>
> To: <topband at contesting.com>
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID: <6FA17FB496BE4653A5A92F3BDC833C43 at ToshLaptop>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
> The r-f loss at the operating frequency in a set of buried radials varies
> with the conductivity and permittivity of the earth in which they are
> buried.
>
> The NEC4.2 study below shows that for poor earth conditions (within about
> 1/2WL from the base of the monopole), the number and length of buried
> radials needed to maintain an r-f loss of a few ohms in the ground return
> rises from that needed for more conductive earth.
>
> In the case of AM broadcast stations, the use of 120 buried radials each
> 1/4-wavelength (in free space) produces a ground system loss of 2 ohms or
> less. This is true no matter what are the characteristics of the the
> earth
> in which those 120 radials are buried.
>
> For a 1/4-wave, unloaded monopole with 35 ohms of radiation resistance and
> 2
> ohms of ground system loss, antenna system radiation efficiency is 35/37 =
> 95% of the applied power (approx).
>
> The FCC requires that a minimum inverse distance groundwave field of 241
> mV/m is produced by an applied power of 1 kW at at a distance of 1 km by
> even the lowest class of AM station (Class C). A perfect 1/4-wave
> monopole
> driven against a perfect ground plane produces about 313 mV/m for those
> conditions.
>
> A typical installation using an unloaded 1/4-wave monopole driven against
> 120 x 1/4-wave buried radials produces about 306 mV/m for those
> conditions -- which field is consistent with a monopole system with a
> radiation efficiency of 95%.
>
> The 241 mV/m minimum field required for Class C AM stations could be
> produced by a 1/4-wave monopole+ground system with about 59% efficiency.
>
> Class A AM stations such as WLW, WJR, WGN etc are required to generate an
> inverse distance groundwave field of 362 mV/m at 1 km for 1 kW of applied
> power. This cannot be done with a 1/4-wave monopole. Most of the Class A
> stations use monopole heights ranging from 180 to 195 degrees.
>
> WJR, Detroit uses a 195-deg monopole system that produces about 403 mV/m
> at
> 1 km for 1 kW of applied power. At their licensed transmitter power of 50
> kW, that field becomes 403 x SQRT(50) = 2.85 V/m, approx.
>
> http://i62.photobucket.com/albums/h85/rfry-100/10m_Vert32Buried_Radials.jpg
>
> RF
>
>
>
> ------------------------------
>
> Message: 19
> Date: Fri, 14 Feb 2014 09:15:59 -0500
> From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
> To: "'Richard Fry'" <rfry at adams.net>, <topband at contesting.com>
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID:
> <!&!AAAAAAAAAAAYAAAAAAAAAF0xXac1rOhFkn7GlcEWNIjCgAAAEAAAAAMEJ5A3lqBAovrQH1mUupABAAAAAA==@nc.rr.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> That's a lot of good information, Richard! Thanks for sharing!
>
> 73,
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Richard
> Fry
> Sent: Friday, February 14, 2014 7:00 AM
> To: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
>
> The r-f loss at the operating frequency in a set of buried radials varies
> with the conductivity and permittivity of the earth in which they are
> buried.
>
> The NEC4.2 study below shows that for poor earth conditions (within about
> 1/2WL from the base of the monopole), the number and length of buried
> radials needed to maintain an r-f loss of a few ohms in the ground return
> rises from that needed for more conductive earth.
>
> In the case of AM broadcast stations, the use of 120 buried radials each
> 1/4-wavelength (in free space) produces a ground system loss of 2 ohms or
> less. This is true no matter what are the characteristics of the the
> earth
> in which those 120 radials are buried.
>
> For a 1/4-wave, unloaded monopole with 35 ohms of radiation resistance and
> 2
>
> ohms of ground system loss, antenna system radiation efficiency is 35/37 =
> 95% of the applied power (approx).
>
> The FCC requires that a minimum inverse distance groundwave field of 241
> mV/m is produced by an applied power of 1 kW at at a distance of 1 km by
> even the lowest class of AM station (Class C). A perfect 1/4-wave
> monopole
> driven against a perfect ground plane produces about 313 mV/m for those
> conditions.
>
> A typical installation using an unloaded 1/4-wave monopole driven against
> 120 x 1/4-wave buried radials produces about 306 mV/m for those
> conditions -- which field is consistent with a monopole system with a
> radiation efficiency of 95%.
>
> The 241 mV/m minimum field required for Class C AM stations could be
> produced by a 1/4-wave monopole+ground system with about 59% efficiency.
>
> Class A AM stations such as WLW, WJR, WGN etc are required to generate an
> inverse distance groundwave field of 362 mV/m at 1 km for 1 kW of applied
> power. This cannot be done with a 1/4-wave monopole. Most of the Class A
> stations use monopole heights ranging from 180 to 195 degrees.
>
> WJR, Detroit uses a 195-deg monopole system that produces about 403 mV/m
> at
> 1 km for 1 kW of applied power. At their licensed transmitter power of 50
> kW, that field becomes 403 x SQRT(50) = 2.85 V/m, approx.
>
> http://i62.photobucket.com/albums/h85/rfry-100/10m_Vert32Buried_Radials.jpg
>
> RF
>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 20
> Date: Fri, 14 Feb 2014 10:02:08 -0500
> From: Bill Cromwell <wrcromwell at gmail.com>
> To: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID: <52FE2FF0.9020005 at gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> On 02/14/2014 09:15 AM, Charlie Cunningham wrote:
>> That's a lot of good information, Richard! Thanks for sharing!
>>
>> 73,
>> Charlie, K4OTV
>>
>>
> The whole topic of radials as it applies to me on my small lot is "put
> in as many as you can". The same probably applies to others on small
> lots. On top band I do not have room in *any* direction for a quarter
> wavelength radial..not even one. In some directions a quarter wavelength
> radial wire might be bent to fit but that begins the many compromises.
> Obviously that setup would have the antenna in one corner of the lot so
> there would be no radials at all in one or two directions. So.. no
> quarter wave radials at all. I have been buying small spools of wire and
> will be adding them to whatever puny little radial field I DO have.
>
> As soon as the ice and snow is gone (maybe in June?) I will be elevating
> my wire antenna the rest of the way to the treetops and adding in the
> radial wires. In the process of elevating the antenna I will learn to be
> ace with a rod n reel <grin>. The whole point of that exercise is to
> *miss* the tree and go over the top. So far I've only ever tried to
> *hit* a spot out on the water. It's not hard to hit the water <wink>. I
> didn't do too badly finding a particular spot on the water with the
> bait. But the tree top is not "over" there. It's "up" there.
>
> 73,
>
> Bill KU8H
>
>
> ------------------------------
>
> Message: 21
> Date: Fri, 14 Feb 2014 08:41:35 -0700
> From: James Rodenkirch <rodenkirch_llc at msn.com>
> To: Top Band Contesting <topband at contesting.com>
> Subject: Topband: Question - optimum number of radials
> Message-ID: <SNT148-W487C0FC2C2747602FAEBC2F09C0 at phx.gbl>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Besides "optimim number(s)," I wonder if there is supporting analysis for
> the connection of the radial ends??
> I have around 80 elevated radials that range from 50 foot lengths, running
> east and west, and 25 foot lengths running north and south (all of that a
> function of being geographically challenged). I have not tied the bitter
> ends together....never really thought about it when I put the radial field
> together but seem to recall reading something about tieing the ends
> together and having a well bounded complete "grid" underthe antenna.
> Thoughts? I tend to think it wouldn't hurt... 72, Jim Rodenkirch K9JWV
>
> ------------------------------
>
> Message: 22
> Date: Fri, 14 Feb 2014 10:45:58 -0500
> From: "Carl" <km1h at jeremy.mv.com>
> To: "Tom W8JI" <w8ji at w8ji.com>
> Cc: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID: <366EBBA2AB1E427787B844AE3CB1479C at computer1>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=response
>
> While Tom touched on the subject yesterday the subject of an individuals
> ground conductivity has to be stressed, continuously it seems. The FCC
> maps
> arent perfect and hams usually dont have the options of perfect siting for
> their verticals as do many of the BC stations.
>
> Home developers often remove all of the good topsoil and sell it. They
> back
> fill with rocky sand and whatever else is cheap or worthless and finish
> with
> a skimcoat of real topsoil just thick enough to grow grass.
>
> My own attempt with 60-65 quarter wave radials 30 years ago at another
> home
> were dismal since the "ground" was pure sand left behind by the glaciers
> with a fresh water table about 4' down. Great for mixing concrete and
> drainage only.
> After I installed a 2X4" fence mesh around the base and out 50' could I
> reliably work DX.
>
> Going to elevated radials here on a granite hill in the same town saved a
> lot of work and works very well.
>
> Carl
> KM1H
>
>
>
> ------------------------------
>
> Message: 23
> Date: Fri, 14 Feb 2014 10:54:14 -0500
> From: "Carl" <km1h at jeremy.mv.com>
> To: <mapa50 at windstream.net>, <topband at contesting.com>
> Subject: Re: Topband: Palomar R-X Noise Bridge
> Message-ID: <183FA4B484E9475C839DD295602A937D at computer1>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
> I used a noise bridge to cut all the RG-11 stacked yagi and phased
> verticals
> phasing lines as well as harmonic stubs here when running a 2 station
> single
> op contest, before SO2R.
>
> Using the station receiver also works well as the backround noise null is
> easily heard. I did that several times when a 9V battery was dead and
> compared results later, they were right on.
>
> Carl
> KM1H
> ----- Original Message -----
> From: <mapa50 at windstream.net>
> To: <topband at contesting.com>
> Sent: Friday, February 14, 2014 12:18 AM
> Subject: Topband: Palomar R-X Noise Bridge
>
>
>>I have a question about using the noise bridge. I have used it cut stubs
>>to
>>1/4 wavelength using 52 ohm cable with no problems. I now need some stubs
>>using 75 ohm cable which I have on hand.
>>
>> Will the same procedure work for 75 ohm that works for 52 ohm cable, or
>> will the different impedance need to be accounted for. I started to cut
>> cable and this question came to me. My first thought is that it will work
>> fine, but I am not sure. I did some searches on the web but found nothing
>> about it. Any help would be appreciated.
>>
>> Thanks, Pat Armstrong
>> KF5YZ
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 24
> Date: Fri, 14 Feb 2014 10:54:41 -0500
> From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
> To: "'Bill Cromwell'" <wrcromwell at gmail.com>, <topband at contesting.com>
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID:
> <!&!AAAAAAAAAAAYAAAAAAAAAF0xXac1rOhFkn7GlcEWNIjCgAAAEAAAAD4cUOc0kI9IhtNMmVa64cABAAAAAA==@nc.rr.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> Hi, Bill
>
> Well, like you, I also live on a fairly small city lot with way too much
> bedrock coming up to the surface and a long concrete driveway, so buried
> radials just aren't feasible for me! So I hung my inverted L in a tall
> tulip
> poplar in one corner of the lot and I ran two elevated resonant radials
> down
> the fence lines - elevated about 5-6 feet. I worked good stuff all over
> the
> world including JA and Indian Ocean, and VK6. If I could hear 'em, I could
> work 'em! BEST thing I EVER did for myself was to build a KAZ terminated
> receiving loop for the low-bands 160-30m, so I could HEAR more! Worked
> great!! And no, I didn't have 100 buried radials, but just a few elevated
> resonant radials will produce very effective results for the transmit
> antenna!
>
> 73
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Bill
> Cromwell
> Sent: Friday, February 14, 2014 10:02 AM
> To: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
>
> On 02/14/2014 09:15 AM, Charlie Cunningham wrote:
>> That's a lot of good information, Richard! Thanks for sharing!
>>
>> 73,
>> Charlie, K4OTV
>>
>>
> The whole topic of radials as it applies to me on my small lot is "put in
> as
> many as you can". The same probably applies to others on small lots. On
> top
> band I do not have room in *any* direction for a quarter wavelength
> radial..not even one. In some directions a quarter wavelength radial wire
> might be bent to fit but that begins the many compromises.
> Obviously that setup would have the antenna in one corner of the lot so
> there would be no radials at all in one or two directions. So.. no quarter
> wave radials at all. I have been buying small spools of wire and will be
> adding them to whatever puny little radial field I DO have.
>
> As soon as the ice and snow is gone (maybe in June?) I will be elevating
> my
> wire antenna the rest of the way to the treetops and adding in the radial
> wires. In the process of elevating the antenna I will learn to be ace with
> a
> rod n reel <grin>. The whole point of that exercise is to
> *miss* the tree and go over the top. So far I've only ever tried to
> *hit* a spot out on the water. It's not hard to hit the water <wink>. I
> didn't do too badly finding a particular spot on the water with the bait.
> But the tree top is not "over" there. It's "up" there.
>
> 73,
>
> Bill KU8H
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 25
> Date: Fri, 14 Feb 2014 11:00:36 -0500
> From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
> To: "'Carl'" <km1h at jeremy.mv.com>, "'Tom W8JI'" <w8ji at w8ji.com>
> Cc: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
> Message-ID:
> <!&!AAAAAAAAAAAYAAAAAAAAAF0xXac1rOhFkn7GlcEWNIjCgAAAEAAAAGfz2YpWO5lGhy14Kf5JOeEBAAAAAA==@nc.rr.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> Yeah, just a few elevated resonant radials can work wonders as you have
> discovered, Carl! And rock does get in the way of buried radials!! The
> models teach that elevated resonant radials should work very well!
>
> 73,
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Carl
> Sent: Friday, February 14, 2014 10:46 AM
> To: Tom W8JI
> Cc: topband at contesting.com
> Subject: Re: Topband: Question - optimum number of radials
>
> While Tom touched on the subject yesterday the subject of an individuals
> ground conductivity has to be stressed, continuously it seems. The FCC
> maps
> arent perfect and hams usually dont have the options of perfect siting for
> their verticals as do many of the BC stations.
>
> Home developers often remove all of the good topsoil and sell it. They
> back
> fill with rocky sand and whatever else is cheap or worthless and finish
> with
>
> a skimcoat of real topsoil just thick enough to grow grass.
>
> My own attempt with 60-65 quarter wave radials 30 years ago at another
> home
> were dismal since the "ground" was pure sand left behind by the glaciers
> with a fresh water table about 4' down. Great for mixing concrete and
> drainage only.
> After I installed a 2X4" fence mesh around the base and out 50' could I
> reliably work DX.
>
> Going to elevated radials here on a granite hill in the same town saved a
> lot of work and works very well.
>
> Carl
> KM1H
>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Subject: Digest Footer
>
> _______________________________________________
> Topband mailing list
> Topband at contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
>
> ------------------------------
>
> End of Topband Digest, Vol 134, Issue 17
> ****************************************
>
>
> -----
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