Carolina windom vs. 135' dipole w/ladder line?
K7jy
designed for 80-10mtrs. operation versus a 135' dipole fed with ladder line (a
la ARRL Handbook)? Any differences in dx performance? How about tvi, rfi, etc.?
Thanks for relaying your experiences. 73, de John, K7JY, Seattle.
Karl Klingman
(probably better) with the 135' ladder line fed dipole. In my opinion, the great
looking radiation patterns displayed in their advertising probably better
illustrate deficiencies in antenna modeling software than the virtues of the
antenna.
73's
Karl AF4IX
Joseph A Rodgers
K7jy wrote in message <19990314101510...@ng115.aol.com>...
>Anyone have any ideas on the comparison between a 132' long Carolina Windom
>designed for 80-10mtrs. operation versus a 135' dipole fed with ladder line
(a
>la ARRL Handbook)? Any differences in dx performance? How about tvi, rfi,
etc.?
>Thanks for relaying your experiences. 73, de John, K7JY, Seattle.
I put up a 135' dipole with ladder line segment about 30' long (a la G5RV) a
few months ago. Have been running barefoot with the antenna strung across
the top of a 50' foot building in downtown Dallas and have had excellent
results so far. The antenna is actually up about 65' above ground now. I
would like to get it farther off the top of the building but have not yet
designed a new support system for it. Have worked much of Europe, Pacific,
and South America so far on 40-10m.
I am getting better sig reports that I was with very old and corroded T33
Tribander at same elevation on the same building.
Give it a try. Band condx are good enough now that it wont take much to get
a pretty good signal out.
Joe N5WY
Dan Richardson
<ka...@mindspring.com> wrote:
>I have used the Carolina Windom and found no magic there. You'd do just as well
>(probably better) with the 135' ladder line fed dipole. In my opinion, the great
>looking radiation patterns displayed in their advertising probably better
>illustrate deficiencies in antenna modeling software than the virtues of the
>antenna.
>
>73's
>Karl AF4IX
Karl,
Do agree with you on the operation of the antennas, however, modeling
software is a tool and as such can be used correctly or improperly. In
the hands of a skilled modeler much information can be obtained. Yes,
software has its limitations, but again, a skilled molder is aware of
that.
73
Danny, K6MHE
Mark Keith
>
> Anyone have any ideas on the comparison between a 132' long Carolina Windom
> designed for 80-10mtrs. operation versus a 135' dipole fed with ladder line (a
> la ARRL Handbook)? Any differences in dx performance? How about tvi, rfi, etc.?
> Thanks for relaying your experiences. 73, de John, K7JY, Seattle.
get as high off the house as you can and use a good quality coax. :IE
213 etc. Or if using LL, make sure the length is correct to minimize rf
on the line. Also could use a choke, but I don't attach chokes to LL
only. Thats why I prefer coax. Easy to decouple and with a good braid,
usually little tvi problems. Dx performance will depend on the height.
But if both were the same height, I'd still rather be on the dipole. I
don't like off center fed antennas at all. MK
Karl Klingman
Dan Richardson wrote:
>
> Do agree with you on the operation of the antennas, however, modeling
> software is a tool and as such can be used correctly or improperly. In
> the hands of a skilled modeler much information can be obtained. Yes,
> software has its limitations, but again, a skilled molder is aware of
> that.
>
> 73
> Danny, K6MHE
Right you are Dan. But in this case it appears to be used as a marketing tool rather
than an engineering tool. A particularly effective one since it would seem that their
claims are supported by scientific data. But, then so might the fractal antenna if
one were to make a judgment based on the claims its proponents rather than actual
field trials.
While antenna modeling certainly has its place in antenna design, most commonly
available (read affordable) antenna modeling software only describes radiation
patterns in a more or less idealized environment since they cannot adequately factor
in terrain, obstructions and other real world factors that greatly effect actual
radiation patterns.
Further, this antenna is an off-center fed doublet with 20 something feet of radiating
vertical coax and I'm not sure how accurately current modeling software predicts the
actual radiation patterns of this particular beastie. While their web site shows some
very impressive patterns, it does not perform (in my particular installation) any
better than my G5RV and on several bands not as well. Which is not to say that the
antenna is bad -- its just that doesn't seem to be any better than any other 100 and
something feet of copper wire slung up in a tree.
But, I wasn't trying to knock modeling software, nor the antenna engineers that use
it. I just think it is wise that the layman view the accuracy of the output of
modeling software as an idealized approximation when presented by engineers and
completely disregarded when presented by sales people.
73's
Karl AF4IX
CJ
is really any practical difference in performance. At least, this seems
to be so on 75 meters. I have hardly ever used my Carolina Windom on any
other band.
I currently use the Carolina Windom at a camp ground. The off-center
feed just happens to fit into the limited space that I have available,
but if my RV space had happened to be centered between the trees that
support the antenna, I would have used center feed and ladder line. And
it would have been cheaper too.
73, CJ K0CJ
Mark Keith
> I currently use the Carolina Windom at a camp ground. The off-center
> feed just happens to fit into the limited space that I have available,
> but if my RV space had happened to be centered between the trees that
> support the antenna, I would have used center feed and ladder line. And
> it would have been cheaper too.
I compared the two at a field day about 3 years ago. I compared an
Carolina windom, 80m size compared to a 80 m dipole that I built on site
and fed with coax. On just a general receieving performance check
between the two using an antenna switch, the windom lost by appx 2 s
units. Same on xmit. Needless to say, the windom went unused the rest of
the night. It was quite a surprise to the owner of the windom. He would
have never noticed otherwise. MK
--
http://web.wt.net/~nm5k
Bill Clarke
most to use and that is what feeds the Carolina Windom and other OCF
antennas similar to it.
--
Bill Clarke W2BLC
W2...@bigfoot.com
Reg Edwards
between the extreme ends, longer than 3/8ths-wave at the
lowest frequency of use, there will be nothing to choose
between them.
Of course, from one day to the next, from one contest to
another, between day and night, from one ionospheric MUF to
another, between summer and winter, there may be
differences. But taking one 12 months of operating with
another, there's no difference whatsoever.
Erect a horizontal wire, as high as you can manage, feed it
roughly in the centre with an open wire line of any old
impedance, and you will have a radiating system second to
none.
--
******************************
Reg, G4FGQ For free software go to:-
http://www.btinternet.com/~g4fgq.regp
******************************
K7jy <k7...@aol.com> wrote in article
<19990314101510...@ng115.aol.com>...
Mark Keith
>
> Since both antennas are horizontal wires, fed somewhere
> between the extreme ends, longer than 3/8ths-wave at the
> lowest frequency of use, there will be nothing to choose
> between them.
But I think the windom we tried was less than 120 ft. It wasn't normally
resonant on 80m with the length of the antenna. If I remember right , he
had to use a tuner. The dipole I put up was full sized and resonant.
Sure , if all the power makes it to the antenna and both wires are equal
length they will usually perform about the same. But, the windom we
tried was a little short. And I think performance suffers against a full
size antenna. I found this to mighty true on 160m. I used big fat
loading coils and still couldn't match the performance I got when I
dumped the coils and went full size.
>
> Of course, from one day to the next, from one contest to
> another, between day and night, from one ionospheric MUF to
> another, between summer and winter, there may be
> differences. But taking one 12 months of operating with
> another, there's no difference whatsoever.
This is true, but when you can get on 80m in the heat of field day and
have one antenna 2 S units over another at any certain time at that
night it's pretty much a given which works best. They had another guy at
another radio that had a G5RV fed in some strange way. I had guys coming
back over to my trailer wanting to use my rig because they complained
the other was an effective dummy load. But my confidence comes in being
as I live on 75m at night and have tried every antenna under the sun
that I can squeeze on this lot.And have tested over the long term. A
good old regular dipole fed with coax is very hard to beat for average
range 80m at night. I prefer the coax so no tuner losses and the other
benefits. MK
--
http://web.wt.net/~nm5k
Karl Klingman
it with coax or a ladder line/coax combo ala the G5RV. I don't run ladder
line either because I have metal storm windows. But, I wish I could. The
points I was really trying to make were:
1) Generally speaking, a wire antenna is a wire antenna and you can make one
as good or better than the commercial ones for a lot less money.
2) There's nothing magic about any of the commercial wire antennas despite
what their advertising says.
73
Karl AF4IX
Reg Edwards
for which there is no explanation. We cannot help but
associate it for ever more with, say, the antenna set up we
happened to have at the time.
It is the hobby's unpredictablity which makes it so
fascinating.
az...@aol.com
k7...@aol.com (K7jy) wrote:
> Anyone have any ideas on the comparison between a 132' long Carolina Windom
> designed for 80-10mtrs. operation versus a 135' dipole fed with ladder line (a
> la ARRL Handbook)? Any differences in dx performance? How about tvi, rfi,
etc.?
> Thanks for relaying your experiences. 73, de John, K7JY, Seattle.
>
For many years I used a dipole fed with open wire line as an all band
antenna. The performance was satisfactory. Just for a change I replaced this
antenna with a Carolina Windom cut for 160 meters. In my experiece, the
windom is much quieter with respect to locally generated noise and is at
least as good a performer on 160 thru 30 meters. I doubt that I will return
to the older configuration.
Alan Zaur (K1MZM)
-----------== Posted via Deja News, The Discussion Network ==----------
http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
Dwight W9YQ
found that a dipole at the same length and height as the
Carolina Windom and fed with ladder line, will consistently
outperform it on all the bands.
... just my experience ... Dwight de W9YQ
Bill Clarke wrote in message
<7cjus3$gce$1...@paxfeed.eni.net>...
K4SQR
I agree the 135' dipole fed via ladder line and a tuner is more efficient
antenna.
73,
Jim, K4SQR
Reg Edwards
how much more efficient is the 135' dipole ?
0.1, 0.5, 1 or 2 S-units ?
By the way, I am not in the least surprised that it is.
--
******************************
Reg, G4FGQ For free software go to:-
http://www.btinternet.com/~g4fgq.regp
******************************
K4SQR <k4...@aol.com> wrote in article
<19990316090638...@ng109.aol.com>...
Dwight W9YQ
occasionally more. This is measured by the S-meter on the
rig Reg.
Dwight W9YQ
Reg Edwards wrote in message
<01be7023$b91b6860$LocalHost@default>...
W6RCecilA
>
> Most the time no less then .5 but typically 1 to 2 S-units,
> occasionally more. This is measured by the S-meter on the
> rig Reg.
The two antennas have somewhat different radiation patterns (both
on transmit and receive) because the Carolina Windom is *designed*
to have vertically-polarized feedline radiation. If the station of
interest is in the middle of a dipole lobe, the dipole will work
considerably better. If the station of interest is in the null of
the dipole, the Carolina Windom will, no doubt, outperform the dipole.
The Carolina Windom is a compromise between a horizontal dipole and a
vertical monopole with the advantages/disadvantages of both.
--
73, Cecil, W6RCA http://www.bigfoot.com/~w6rca
Mark Keith
>
> At the resonant point on 80m, the G5RV has only about a 5:1 SWR on the
> coax. That's not enough of a loss to put it in the pathetic range IMO.
> However, it's resonant at the low frequency end of the band.
Yea, but I don't know what all he had attached to his in the way of
feedline etc. He had a combo of a tuner , ladder line, and coax. I don't
know the SWR , but the performance WAS pathetic. This was the whole
reason I had brought the goodies to make my own dipole. This same guy
had stuck us all on this same pathetic antenna the year earlier. That
previous summer I swore I would never,ever use his G5RV again. Well, the
next year I came back, and sure enough,it was his same old tired out
G5RV and the new windom that another guy had brought.
The first words out of my mouth was , I ain't talking on that crap! And
proceded to build the dipole. I sure was glad I did too. It turned out
to be the only antenna that worked on 80m. The windom made that
particular g5rv look like a dummy load. The dipole made the windom look
like a dummy load. MK
--
http://web.wt.net/~nm5k
Karl Klingman
That's not been my experience. I have a G5RV and a Carolina Windom both
at roughly the same height at 90 degree angles with the Windom running in
the favored direction (broadside east-west). I have them on an A/B switch
so that I can flip back and forth. The G5RV is almost always as good as
the Windom and usually 1 or 2 S units better. So, I would venture that
the 135' dipole with ladder line will also be better -- unless I have a
magic G5RV. But, of course your mileage may vary.
I haven't pulled them apart to see how well they are constructed, but
since the Carolina Windom has both a balun at the point where the antenna
is attached to the radiating coax and a "line isolator" where the
radiating coax connects to the feedline, it might be possible that the
performance difference lies therein.
Karl AF4IX
Mark Keith
> The first words out of my mouth was , I ain't talking on that crap! And
> proceded to build the dipole. I sure was glad I did too. It turned out
> to be the only antenna that worked on 80m. The windom made that
> particular g5rv look like a dummy load. The dipole made the windom look
> like a dummy load.
P.S. Another note, just to clarify my stubbornness to use my own antenna
that year. Not that I wanted to be a smartass, but the guy that kept
insisting on the G5RV didn't even have to suffer with it after midnight!
He'd hit the rack in his motorhome while me and a very few others ate
the bugs trying to get out on a dummy load. Gave me a migrane as I don't
really care for contest type operating anyway, and to do it on a
non-antenna is the pits for me. I'd rather go for a root canal. MK
N2EY
>Subject: Re: Carolina windom vs. 135' dipole w/ladder line?
>From: Mark Keith <nm...@wt.net>
>Date: Mon, 15 Mar 1999 15:07:02 -0600
Mark,
I had a similar experience on FD several years ago. I put up a homebrew trap
inverted V for 80 and 40 - apex at 40 feet, while the other operating position
put up a manufactured Carolina Windom between two trees at 50 feet. With
virtually identical rigs, the inverted V was getting stations on the first or
second call, while the Carolina Windom was getting them on the fourth, fifth or
sixth - if at all. On 80 and 40, anyway. I don't know why it was so inferior,
but the owner was sure disappointed. The windom was brand new, right out of the
box, and cost dozens of times what my homebrew inverted V did.
Both antennas were used without tuners, and had low SWR (well under 2:1) at the
shack end of the coax.
In FD 1995, that inverted V made 469 QSOs on 80 and 40 CW from NNJ in about 14
hours, with the apex at 40 feet and the ends at about 25 feet. Rig used was a
homebrew CW transceiver with 100 watts output. (The rest of the time was spent
on 20 meters with a different antenna). Anybody beat that with a Carolina
Windom?
73 de Jim, N2EY
Jesse Touhey
wrote:
>Anyone have any ideas on the comparison between a 132' long Carolina Windom
>designed for 80-10mtrs. operation versus a 135' dipole fed with ladder line (a
>la ARRL Handbook)? Any differences in dx performance? How about tvi, rfi, etc.?
>Thanks for relaying your experiences. 73, de John, K7JY, Seattle.
John, when operated from the same height, the
Carolina will radiate less efficiently, and
produce more rf in the shack than the ladder line
fed dipole. When used with a good impedance
transforming device, the ladder line fed dipole is
a very good multi band antenna system.
73, Jesse, W7OKI
Alurk50
interested in 75 and 40....works great on 40!
Al Urkawich K B 1 L I
W6RCecilA
>
> I also use a 130 ft dipole fed with 75 ohm twin lead....works great!! Mostly
> interested in 75 and 40....works great on 40!
What is the matched line loss on 7MHz?
Wes N7WS
wrote:
>I also use a 130 ft dipole fed with 75 ohm twin lead....works great!! Mostly
>interested in 75 and 40....works great on 40!
>
>Al Urkawich K B 1 L I
I would like to know the dimensions of "75-ohm" twinlead.
Can you tell me what the conductor diameter and wire spacing
are?
Thanks,
Wes N7WS
Jesse Touhey
(Alurk50) wrote:
>I also use a 130 ft dipole fed with 75 ohm twin lead....works great!! Mostly
>interested in 75 and 40....works great on 40!
>
>Al Urkawich K B 1 L I
Al, on 40 and the higher bands you would have a
less loss system if you switched to 450 ohm ladder
line or open wire (open wire best). When operated
on 40m your feed line is operating with very high
VSWR (>26:1).
73, Jesse, W7OKI
Wes N7WS
Al replied to me via email and indicated that this "75 ohm"
line was constructed of two 18AWG wires spaced 1.5".
He didn't say what held the wires apart, but it almost
doesn't matter as long as the dielectric loss tangent is
small. He also didn't say how long the line was.
The line Z0 is about 500 ohm, not 75 ohm. At 7 MHz, the
loss in 100 ft of this stuff would be about .12 dB/100'.
EZNEC says that the feedpoint impedance of Al's dipole on 7
MHz @ 40' high is about 4900 + j510. The SWR is about 10:1
at the load end and a bit under 9:1 at the input end
(assuming 100' of line)
With this load and 100' of line, the total loss due to the
elevated SWR is about 0.6 dB. Interestingly, if the line is
100 ft long and the dielectric constant is around 1.15 or
so, the input impedance of this arrangement is pretty good.
Fifty ohmish and not too reactive.
Alurk50
I meant 450 ohm ladder line!
Al KB1LI
Alurk50
I meant 450 ohm ladder line!!!
Al
KB1LI