EFHW: You're talking about 270 ft. on 160m.
Be sure to use a good RF-Choke at the feedpoint in addition to however you
match it.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim Allen
Sent: Wednesday, August 20, 2014 3:27 PM
That said, I really wonder why I worry about radials after spending almost
all day yesterday reading about EFHWs. For my situation, that might be a
very amusing choice indeed.
73 de W6OGC Jim Allen
On Wed, Aug 20, 2014 at 7:32 AM, Rick - DJ0IP / NJ0IP <Rick@dj0ip.de> wrote:
> Refference Petlowany Coils:
>
> Jim (A), I thought you said you were a "retired" lawyer.
> With that contraption in back yards, you'll have XYL's lined up for
> miles, wanting you to help them file for a divorce.
> Or was that the idea behind this suggestion? ;-)
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim
> Allen
> Sent: Tuesday, August 19, 2014 11:11 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] 160 Meter Problem
>
> If you have a problem putting out radials for your vertical, why not
> try Petlowany coils?
>
> I have a home brew clone S9v31 with which I use 4 Petlowany coils.
> See the photo at
>
> http://forums.qrz.com/showthread.php?444568-Petlowany-or-Petlowaney-Co
> ils-as -Ground-Radial-Replacements&highlight=Petlowany+coils
>
> 73 de W6OGC Jim Allen
>
>
> On Tue, Aug 19, 2014 at 3:51 PM, Rick - DJ0IP / NJ0IP <Rick@dj0ip.de>
> wrote:
>
> > Hi Jim,
> >
> > It was nearly midnight last night when I read the entire presentation.
> > I sure wish I could have heard the audio that accompanied it.
> >
> > Yes indeed, I overlooked the "vertical rules on 160m". Missed that
> point.
> > That's it in a nutshell! That pretty much nails it!
> >
> > Total waste of time to even fool with horizontal antennas on 160m
> > unless you just want to rag chew with the local yuks. It took me
> > many years to arrive at this conclusion. What a difference it made
> > to my contest scores once I switched to verticals!
> >
> > I haven't gotten any further yet with your material.
> > My XYL had surgery today and I spent the entire day in the clinic.
> > As I wrote earlier, there is so much meat in your paper, it will
> > take a couple of days to go through all of this.
> > While hanging out in the clinic today, I wished I had had the time
> > to print your stuff out and take it with me, but it was just too
> > late last
> night.
> > The reading material in the waiting room wasn't exactly my flavor.
> >
> > Also, as a result of reading your paper, it reminded me that I
> > hadn't uploaded my own folded radial vertical to my web yet, so I
> > did that this evening, including the EZNEC model of the antenna. It
> > is a simple, effective 40 DX antenna requiring very little floor space.
> >
> > Mine had only one bend in the radial (copied from a Moxon design in
> > RadCom).
> > From your link to K2VA I saw it still works good with multiple bends
> > which make 80 and 160m more feasible.
> > Tnx for the tip. Hadn't ever heard of that before. I have lots of
> > reading to do!
> >
> > Here's a link to my vertical with the single folded radial:
> > http://www.dj0ip.de/vertical-antennas/40m-low-space/
> >
> > 73 - Rick, DJ0IP
> > (Nr. Frankfurt am Main)
> >
> >
> > -----Original Message-----
> > From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim
> > Brown
> > Sent: Tuesday, August 19, 2014 7:14 PM
> > To: tentec@contesting.com
> > Subject: Re: [TenTec] 160 Meter Problem
> >
> > On Mon,8/18/2014 10:16 PM, Rick - DJ0IP / NJ0IP wrote:
> > > Jim, I didn't understand the point on slides 4 and 5.
> > > I concur with everything you wrote.
> > > Perhaps you mean where you wrote 130 ft. height for a horizontal
> > > antenna is "low" on 160m.
> >
> > Well, remember that these slides accompany my talk, and also this
> > talk was to the Pacificon Antenna Forum, which draws folks a
> > somewhat above average knowledge of antennas. Ya hadda be there. :)
> >
> > The fundamental principle at work is that a horizontal antenna that
> > is low as a fraction of a wavelength is an inefficient antenna, both
> > because of ground losses and because all the energy goes more or
> > less
> straight up.
> > I'd
> > call any horizontal antenna lower than a quarter wavelength low.
> > Most of us are stuck with low antennas for 40M and below.
> >
> > But what is is about the line "Verticals RULE on 160M" that you
> > don't understand? To me, that says don't even consider a horizontal
antenna.
> > Further, the fact that the rest of the talk covers only vertical
> > antennas (with various forms of counterpoise) should tell you
> > SOMETHING. :)
> >
> > > Well my main point is, we have good dB numbers shown for different
> > > vertical solutions, but there are no dB numbers shown comparing a
> > > low dipole at a typical height one would have in a city - say 50 ft.
> > > max, to anything vertical.
> >
> > You're right -- I almost never see that sort of comparison, which is
> > what I did in the other link I gave. It compares vertical and
> > horizontal antennas at various heights on 80, 40, and 20. The 80M
> > plots are easily scaled for 160M. Simply double the heights shown on
> > the
> horizontal axis.
> > So a resonant horizontal dipole at 80ft on 160 would behave like a
> > resonant 80M dipole at 40 ft on 80M.
> >
> > Also, both of those presentations are 1 hour talks, and especially
> > with the 160M talk, I had to have my roller skates on to get through
> > it in that time.
> > :)
> >
> > > There the difference is larger (in dB) than the difference between
> > > a good vertical and a great vertical.
> >
> > Yes. And the primary difference between a mediocre vertical and a
> > great one is the counterpoise/radial system.
> >
> > Another tutorial you might find interesting is this one.
> > http://k9yc.com/VerticalHeight.pdf It doesn't address 160M, but it
> > clearly shows the effects of the quality of the soil on a vertical
> > antenna, and also the value of mounting vertical antennas higher.
> >
> > 73, Jim K9YC
> >
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> >
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