Some kind person got permission and put this copyrighted paper online:
https://www.okdxf.eu/files/Ground%20Systems%20-%20Brown,%20Lewis%20and%20Epstein%201937.pdf
Dr. Brown was noted for such things as having assistants erect a dipole,
connect a 50 KW transmitter, and take impedance measurements.
Also:
https://ipo.llnl.gov/sites/default/files/2020-07/NEC5%20Validation%20Manual%20092419.pdf
Has an extensive discussion (near the end) of radial systems.
All free access to read..
JIm/VEZ
On Tue, Dec 29, 2020 at 2:37 PM fmoeves <fmoeves@twc.com> wrote:
> I was under the impression that If you have elevated radials and if you
> take even one to the ground you might as well move all to the
> ground..??Fred KB4QZH
> -------- Original message --------From: donovanf@erols.com Date:
> 12/29/20 12:30 PM (GMT-05:00) To: topband@contesting.com Subject: Re:
> Topband: Elevated Radials - will radials on ground help? Hi Clive, A second
> resonant radial is a good idea, but not because it might cancel
> horizontally polarized radiation. Why? Because -- just like a Beverage -- a
> horizontal wire close to the ground has no significant horizontally
> polarized radiation. Essentially all of the horizontally polarized
> radiation is lost to ground losses. 73 Frank W3LPL ----- Original Message
> -----From: clive@gm3poi.com To: donovanf@erols.com, topband@contesting.com
> Sent: Tuesday, December 29, 2020 5:25:05 PM Subject: RE: Topband: Elevated
> Radials - will radials on ground help? Frank what about adding another
> radial to each vertical to cancel the Horizontal polarisation from the
> single radial. 73 Clive GM3POI -----Original Message----- From: Topband
> <topband-bounces+clive=gm3poi.com@contesting.com> On Behalf Of
> donovanf@erols.com Sent: 29 December 2020 17:01 To: topband@contesting.com
> Subject: Re: Topband: Elevated Radials - will radials on ground help? Hi
> Dan, Your small lot is an ideal candidate for K2AV's folded counterpoise.
> Contact K2AV for guidance, he's helped countless successful users.
> www.k2av.com A few clarifications regarding radials and gain: Radials
> have absolutely nothing to do with gain. They only reduce ground losses
> within a fraction of a wavelength of the antenna. The realistic
> opportunities to further reduce losses are: - install the antenna on salt
> march like K3ZM and W1KM, or - install the antenna closer than one mile to
> sea water in the foreground of the antenna for at least a few miles in the
> most important directions. But you've already done that. Bravo! Good luck!
> 73 Frank W3LPL ----- Original Message ----- From: "Dan Flaig NP2J" <
> dan@np2j.com> To: donovanf@erols.com Sent: Tuesday, December 29, 2020
> 4:41:40 PM Subject: Re: Topband: Elevated Radials - will radials on ground
> help? On 2020-12-29 10:06, donovanf@erols.com wrote: > Hi Dan, > > An
> inverted-L with one elevated radial has lots of room for > improvement, >
> almost anything will improve what you now have. > > How much improvement
> you can achieve is mostly determined by site > limitations, copper wire
> expense, how much work you're able do > yourself or pay someone else to do
> for you. > > Eight radials, 70 feet long is the absolute minimum number of
> radials > if you lay them on the ground. Sixteen 80-foot radials will be
> much > better, > 32 100-radials will be significantly better than that.
> Finally 60 > 125-foot > radials will be within one dB of the best you could
> achieve. > > This is the classic reference: > >
> ncjweb.com/bonus-content/k3lcmaxgainradials.pdf > > If you continue to
> use resonant elevated radials, four is the minimum > number your should
> shoot for, but unfortunately its difficult to get > all > four elevated
> radials to carry similar amounts of current. Eight > elevated > radials is
> much better. > > The K2AV Folded counterpoise is another alternative to
> your > current single elevated radial. > > Good luck! > > 73 > Frank >
> W3LPL > > ------------------------- > > From: dan@np2j.com > To:
> topband@contesting.com > Sent: Tuesday, December 29, 2020 1:58:53 PM >
> Subject: Topband: Elevated Radials - will radials on ground help? > > Hello
> fellow Topbanders! > > Had lots of fun in the Stew, thanks for the contacts
> everyone! > > Looking forward to the CQ160 and as always trying to find a
> way to > improve antenna performance.... so looking for advice > > I am
> currently using a pair of Inverted L's each having a single > elevated
> radial. > The feedpoint's and elevated radials are 10-12 feet above ground.
> > The soil is fairly rocky. > Also quite a bit of "Bush" growing fairly
> high except below elevated > radials where I have trimmed back the bush. >
> > I am wondering if I should lay radials on the ground, particulary near >
> > the feedpoint's? > Any advice?? > > 73 > Dan K8RF/NP2J >
> _________________ > Searchable Archives:
> http://www.contesting.com/_topband - Topband > Reflector Frank, Thanks
> for the reply. My lot is narrow and runs North to South. The elevated
> radials run towards the North, figured might have small amount of gain in
> that direction. I could maybe add one or two additional elevated radials
> but they would be only angled a few degrees plus or minus from the current
> single radial going North. I am on side of ahill at abt 300 feet elevation
> about 3/4 of a mile from the North shoreline. 73 Dan _________________
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>
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