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BEST DX ANTENNA: QUARTER WAVE or HALF-WAVE VERTICAL??
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- čas přidán 4. 09. 2024
- Using modelling software, which one comes out on top? The quarter wave or the half wave?
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Good to show the differences Tim. Its really not worth talking about but great to know. The 1/2 wave has a big benefit of no radials but quarter wave is half the height. What this doesn't take into account is surroundings. I was shocked to see the difference between my OCFD and a vertical and my garden is open on side. I will try to make a video on it soon. Good to see you back.
Nice observation about the OCFD Colin and thank you!!
Glad to see you back, Tim. My experimentation multibanding vertical half waves using a 49:1 leads me to believe that any dB benefits are cancelled by the loss introduced by the transformer (which, if my S21 measured losses are accurate, show 1dB down at 20m and 40m).
Good point
Yes they do get hot!
Thank you so much Tim. Good and useful information.
I recently compared in real life 1/2 wave versus 1/4 wave (with elevated radials).. using reverse beacon the 1/4 wave beats the 1/2 wave on long distance. Using the 1/2 wave on 20m the distance is up to 4000 km. However the 1/4 wave consistenly reaches the 10.000 km and even new zealand. It seems the radials really make a huge difference which makes sense.
Interesting points!!
Good video Tim.
I've also been modelling half-wave verticals in MMANA. I've had this slightly mad idea that I want to put an EFHW vertical (for 20m) on an 18m DX Commander pole at my home QTH to get it above the roofline (which will obviously put the feed point at approximately 8m above the ground).
I've been modelling gain vs take off angle at various heights above the ground. Strangely my results were approximately 1db down on yours so I don't know what I entered into MMANA which was different from you..........maybe my ground settings are a little different.
Great to see you back on CZcams again. Keep up the good work.
Ah right - I was using real ground on MMANA. Nothing mad about your idea!! Thanks James 73
Tim ,great to see you back but don’t feel pressurised to keep churning out videos,much as I enjoy them.
Thank you David
Welcome back. Cheers from the across the pond
Thank you Joe! 73
Yep, that matches my (limited) experience between the two -on the radio they sound pretty much the same. So I put my EFHW on its side, and discovered that the difference between horizontally and vertically polarised signals is *very* noticeable, and quite variable. The downside is, it's another knob to switch while trying to tune in a station :)
Thanks mate. I run a 40m-10m EFHW (a coil for 80m, very narrow b/w on 80m) and a homebrew 49:1 designed based on videos from Steve Ellington. Just so that i understand you clearly.....did you see better performance with your EFHW when it was setup horizontally or when it was setup vertically. - VK3TWC
@@coderdojoAN I get *different* performance. When horizontal, it mostly picks up horizontally polarised RF, so if the station I'm trying to work is mostly horizontally polarised, then it's better received on the EFHW. I've also got a 1/4 wave which I keep vertical, and I'll switch between them to get the best receive signal. However, the polarisation is not stable, and can change over the period of a few seconds to minutes. So the best technique would be to use two transceivers, one for each antenna, and then you could listen/transmit on the one with the better signal. However, that's too rich for my money, so I just use a simple antenna switch to see if a station is louder on the other antenna :)
@@Lastaii Thanks mate that was really helpful. I live in a suburban plot (Melbourne, Au) with the usual challenges i.e. space constraints, RFI, etc. The EFHW was the best option for me, i've got it setup as an inverted V with the middle at ~33ft. I also have another 20m half wave vertical which i am thinking of re-tuning for use on 40m as well. I see your point about polarization and the fact that it could change with the station, weather, number of other factors, etc. Some more interesting experimenting to do... lol. Thanks and stay safe. - VK3TWC
Welcome back Tim
Thank you Jes 73
Excellent video. Been experimenting with the 1\4 wave DX commander. Mark , 2E0MSR.
Thanks Mark! 73
The difference for myself in an extremely windy Scotland, is that the 1/4 wave is generally close to unbreakable. The vertical HWEF, is very much more vulnerable.
In practice, my vertical HWEF really wasn’t beating out the 1/4 wave on 20m at all, although I’m running about 32 radials. And, for reasons unknown as yet, the 1/4 wave is slightly better at avoiding RFI.
It’s a snake’s wrestling match comparing antennas, and the modelling never really reflects everything physically there insitu. Build them and see is almost unavoidable in the end.
Very fair point.
Tim could you do a comparison between a halfwave vertical and a vertical dipole for say 10m band obviously the halfwave vertical is more practical as it can change bands if fed with a 49-1. I am interested in the modelling side I don't seem to get my head around it.
I'll add that to the list no problem
Welcome back Tim. 73 Joe
Thank you Joe, 73.
Easy to make assumptions as to what is best but I have a quarter wave vertical , a half wave horizontal (EFHW) and a 20-10 meter magnetic loop and no matter how much I try I can't get them to be predictable enough to claim one is best ! What I have found is the depending on conditions one will work better than the others and it is a bit pot luck as to which is best. Hope this helps (confuse the issue lol) M7BLC
Yes - there are so many variables!
Hey Tim have a request wondering if you might do a video on the use and application of a 75 ohm matching stub. Discuss how to use it when to use it how to make it how to measure it and basically what it's designed to do and what would be the benefit of using one. Thanks in advance
I will add it for consideration!
@@timg5tm941 thanks! What length of twin lead (450 or 300 ohm ladder line) do you recommend to feed a linear loaded doublet which is made from 450 ohm ladder line and also has an additional center wire attached for shortening the length, it's legs are about 33' or 10m long each side
Very interesting, coincdentially I'm just about to (finally) setup my transceviers to switch between a 6BTV with radials and an 80m multiband end fed, it will be interesting to see the differences between the two in real life. Another excellent video Tim - always clear and easy to understand.
Thank you Al! Hope you are going to make a video on that comparison yourself? 73
I was only saying earlier today that you had disappeared from the scene!👍☘️
Ah … well I’m still about, sort of! 73
I do very well with a 5/8th wave verticle.
They work very well Eric
@@timg5tm941 You have a fantastic channel, thanks for sharing your knowlege with us 🇺🇸✌,
@@ericdee6802 you are too kind Eric. ☺️ 73
welcome back!
Thank you!
👍👏👏
What about a Slim-Jim antenna for the band in question
Hi David it’s a half wave I’m sure, so should be close to the modelling here.
How would a 49:1 efhw fair say a foot off the ground ran up a 10m pole so you could work 20m with no radials and would be a halfway vertical??
Are you asking if that vertical would be a half wave Andy (just for me to clarify)?
@@timg5tm941 it's OK Tim,I've just got the updated clamps for my classic so gonna use that as working alot better than my efhw :)