Home |
Search |
Today's Posts |
#21
![]() |
|||
|
|||
![]()
"Mark Keith" wrote in message
om... "Thierry" http://www.astrosurf.com/lombry wrote in message ... Ok Mark, for sure for DXing a dipole or a windom is not a beam... I'd rather have the coax fed dipole over the windom any day though...I Hi, No. For a true dipole and get a low impedance etc I prefer by far the ladder line; The coax is easier but is less performing This is not much difference, but measurable. I always prefered the optimum solution. bet many people would think it's a beam , the way it will most likely trounce the average windom. I tried one "windom" at a field day against a coax fed dipole. The dipole won by 2 s units in any direction. Thats about what you would see going from a coax dipole to an average beam...:/ Or by changing from 100w to 500w-1 KW... Ok. I will see but 2 S-unit are much. What is sure is that the radiation pattern of a carolina windom is next over a dipole : http://www.astrosurf.com/lombry/Radi...on-pattern.gif it is much more omnidorectionnal what could explain is overall better performance. My objective is Dxing first as for local QSOs this is not a problem to get S9+. If it's working local, why would it not be working dx ok? Why the change to an antenna which basically will be the same, assuming Local is not DX. High takeoff angle vs. very low. This is a huge difference if you check your receive strength signal. 73 Thierry, ON4SKY element lengths are fairly close for a given band, barring any changes in feedline efficiency? IE: I assume you are going to switch from a G5RV to a windom.... Thinking about either one of those antennas makes me want to take up golf... I don't like either one. It's no secret though.... ![]() The only thing the G5RV has going for it, is it is nearly a EDZ on 20m. But it's a reduced efficiency version compared to one fed in a normal manner... Coax to a choke to ladder line as a feedline is no way to live for a serious dx'er who wants most of his power to actually be radiated by the antenna element...The windom is not much better in this regard....Or at least the ones I've seen. I know very well that DX performances will be more than limited, all the more in SSB, but this is a temporary solution waiting for a small beam 3-or 4 ele. You still don't mention which band/s though... There are fairly simple wire antennas much better for dx than the usual all band compromise wire antenna. IE: extended double zepps, phased parallel dipoles, etc, etc. I would use something along those lines if I wanted to dx say 20m or up...If you want to dx 80/40, you might consider a bobtail curtain or variant, or a good vertical. Trying to increase the dx potential by changing from one semi lame antenna , to another semi lame antenna strikes me as counterproductive. But, it's your yard and $$$.... :/ MK |
#22
![]() |
|||
|
|||
![]()
No, no, no.. I said the vertical element was 20' off the
ground....bottom of the vertical feedline 20' off the ground, means antennas height in the center was about 40-50'. dt On Sat, 18 Sep 2004 11:51:18 +0200, "Thierry" http://www.astrosurf.com/lombry wrote: "dmr" wrote in message .. . I have used 160M Carolina windoms for the past 5 years or so and have found them to be really good performers. The higher you can get the vertical element off the ground the better (I have had good results with it only 20' off the gorund....Radioworks recommends more). I have never modeled it, nor had experience with G5RV, but compared to a half wave dipole at similar height, my "impression" is that it performs at least as well, probably better, plus multiband. Beward you will need to use a tuner with it, and if you are running legal limit, be careful of your SWR's as you can burn out the balun or RF choke (they are not traps). Hi, 160m long 20' high ? That must be interesting and u had to confirm over 100 dx with such a length... I very well know these problems of SWR etc,and many others. I am an OT you know,... Hi! I learnt the lesson in the past in experimenting live a bad SWR... youth errors as one tells... but interesting because I never more forget the lesson, like many others in experimenting myself. With some respect it it far better to be chocke a second and get a little blister due to a SWR over 5:1 using a kW amp that having hours of theory... because you cannot fix your idea on concrete things. For the rest, of course the heigth (and length) are VERY important, all using a dipole or windom all work fine or almost from 8m high and 20m long and up. Below your radiation pattern is seriously affected compared to the ideal solution (say 2-lamba over 12m high). And you feel that very well when trying to call CQ DX and even simple CQ up to 5000 km away. To get an idea simulate these specs in modeling software like multiprop that use a VOACAP engine, or even nec, hfant and others. See my best site for detail. Thanks for the help. 73 Thierry, ON4SKY There has been a lot of debate about this antenna, but I can tell you the 160M version works quite well on all bandsl. GL es 73 Dan (k0dan) On Fri, 17 Sep 2004 15:35:28 +0200, "Thierry" http://www.astrosurf.com/lombry wrote: "Cecil Moore" wrote in message ... Walter Maxwell wrote: If I may put in my two-cents worth, a dipole is a dipole. The G5RV is a dipole and the Caroling Windom is a dipole. Hi Walt, I don't know if you know or not, but the Carolina Windom is designed for the vertical section to radiate so it has a radiation pattern which is a combination of a dipole and a vertical. Indeed, all the interest of the thing..., hence my question. But I wonder also about the QRM pick-up along this vertical segment... I will have the answer in two weeks. Thierry, ON4SKY -- 73, Cecil, W5DXP -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#23
![]() |
|||
|
|||
![]()
Thierry wrote:
But I wonder also about the QRM pick-up along this vertical segment... I will have the answer in two weeks. It is designed to radiate some vertically polarized energy so it is also designed to receiver some vertically polarized energy. That would render the Carolina Windom virtually useless at my QTH. -- 73, Cecil, W5DXP -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#24
![]() |
|||
|
|||
![]()
Thierry wrote:
Without speaking about heigth above ground, QRG and length, how do we explain the more or less omnidirectional pattern against a dipole, see diagram at http://www.astrosurf.com/lombry/Radi...on-pattern.gif if there is no radiation from the coaxial ? The vertical coax section between the impedance matching device at the feedpoint and the RF choke is designed to radiate and it does. The coax between the RF choke and the source is designed not to radiate. -- 73, Cecil, W5DXP -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#25
![]() |
|||
|
|||
![]() "Cecil Moore" wrote in message ... Thierry wrote: Without speaking about heigth above ground, QRG and length, how do we explain the more or less omnidirectional pattern against a dipole, see diagram at http://www.astrosurf.com/lombry/Radi...on-pattern.gif if there is no radiation from the coaxial ? The vertical coax section between the impedance matching device at the feedpoint and the RF choke is designed to radiate and it does. The coax between the RF choke and the source is designed not to radiate. -- Hi Cecil, it is well what i though, but in my case this is a Carolina Windom like on this drawing http://www.astrosurf.com/lombry/Radi...windom-dwg.gif The balun is attached to the wire and there is no segment above it. the coax enter the balun and the otehr side goes to the TX hence my question. And is this design still a Carolina Windom, excepted the segemnts of 1/3 2/3, it looks more to a hybrid between the dipole and the Windom... isn't it ? And on this model, if it uses a choke balun (what is not sure) the coax 'd not radiate RF, othewhise of course if radiate much, like an vertical Thierry, ON4SKY 73, Cecil, W5DXP -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#26
![]() |
|||
|
|||
![]()
it is well what i though, but in my case this is a Carolina Windom like on
this drawing http://www.astrosurf.com/lombry/Radi...windom-dwg.gif The balun is attached to the wire and there is no segment above it. the coax enter the balun and the otehr side goes to the TX hence my question. And is this design still a Carolina Windom, excepted the segemnts of 1/3 2/3, it looks more to a hybrid between the dipole and the Windom... isn't it ? And on this model, if it uses a choke balun (what is not sure) the coax 'd not radiate RF, othewhise of course if radiate much, like an vertical Thierry, ON4SKY What you have is the standard Off Center Fed antenna. A true Windom is fed with a single wire about 1/3 the distance from one end. Many are calling the OCF antenna a Windom which it is not. The OCF antenna is often called a Windom by mistake. The Carolina Windom has about 6 meters of coax that is vertical below the horizontal part and then a common mode choke. The vertical is suspose to radiate some signal for DX and the horizontal is for a higher angle of radiation for the close in stations. I don't know if it actually works this way in practice , but that is their selling point. Here is a URL for the Carolina Windom. http://www.radioworks.com/ccwcover.html |
#27
![]() |
|||
|
|||
![]()
Thierry wrote:
it is well what i though, but in my case this is a Carolina Windom like on this drawing http://www.astrosurf.com/lombry/Radi...windom-dwg.gif The balun is attached to the wire and there is no segment above it. the coax enter the balun and the otehr side goes to the TX hence my question. And is this design still a Carolina Windom, ...? Good Grief! No, that is *NOT* a Carolina Windom, which is an antenna sold by Radio Works. Hopefully, they have it copyrighted and therefore can object to the above BS. See it at http://www.radioworks.com/ccwcover.html The antenna you mention is simply an off-center-fed dipole, not really a Windom at all. (Why are people with 65 IQ's allowed to build web pages?) -- 73, Cecil, W5DXP -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#28
![]() |
|||
|
|||
![]() "Cecil Moore" wrote in message ... Thierry wrote: it is well what i though, but in my case this is a Carolina Windom like on this drawing http://www.astrosurf.com/lombry/Radi...windom-dwg.gif The balun is attached to the wire and there is no segment above it. the coax enter the balun and the otehr side goes to the TX hence my question. And is this design still a Carolina Windom, ...? Good Grief! No, that is *NOT* a Carolina Windom, which is an antenna sold by Radio Works. Hopefully, they have it copyrighted and therefore can object to the above BS. See it at http://www.radioworks.com/ccwcover.html The antenna you mention is simply an off-center-fed dipole, not really a Windom at all. (Why are people with 65 IQ's allowed to build web pages?) the 65 IQ has nothing to do with it. The problem is that the manufacturer sold it as a Windom... and it is as it is off center fed... with a simple balun and coax, but the opposite is not true. Ok it is not a carolina, it 's only me who mixed both designs. 73 Thierry -- 73, Cecil, W5DXP -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
G5RV or 135 foot doublet or Carolina Windom? | Antenna | |||
Carolina Windom Problem...any suggestions | Antenna | |||
OCF Dipole vs. G5RV vs. Carolina Windom ??? | Antenna | |||
Off Center Fed Dipole: the "Windom" experience. | Antenna | |||
Off Center Fed Dipole: Windom HSQ | Antenna |