Oh my word. This guy explains it so well. Im currently studying for my Ham licence and want to start building an inverted V antenna for the 20 band. I have been looking all over the internet for a good exrantion on the inverted V antennad, but this is the best onse so far.
Thanks for that, we have a saying (army signals) 'KISS - Keep It Simple Stupid'.. Being a soldier of course I'm on a budget, so I'm running a Sigma 2011 5/8 CB antenna tuned to 10. A trapped WARC dipole and a Hustler 5BTV.. My sigma is roof height, the WARC dipole is a sloper from the chimney to 10ft above the ground and the Hustler is ground mounted with TWO radials - and I've worked the work (running barefoot too, 100w).. LOVED this video and hope it inspires people who think they can't work DX with modest means, you absolutely can!.
Excellent points about the over-emphasis on low-angle radiation and the reality of multi-hop in signal propagation in DX work. I have an 80-10m EFHW mounted atop a six foot fence and often work stations over 4000 miles from my QTH running 5w. Jim - N7RCS
Thanks, Peter, for another great video and a concise explanation of the inverted vee. I live in the city and originally used a G5RV in an inverted vee. I replaced it with a 65' Windom also in an inverted vee configuration. The apex is about 40' AGL. My angle is close to 90°. I've been happy with my results. I also have a DXcommander Rapide and a Magnetic loop both for 40-10m. I think given the size of my lot that is probably enough antennas. Take care KC8WVG 73
Excellent video! From my 60 plus years of DXing I can confirm that your are spot on! I typically ( in recent years anyway as I have had the big 4 and 6 element full size arrays) use only dipoles, inverted Vs and sloping dipoles. I prefer the dipoles of course but the inverted V and the sloping dipole work fine when I don’t! I have actually worked over 100 countries over the span of one weekend several times with dipoles no higher than 50 feet. On some occasions in was 100 countries on multiple bands in one weekend. Once it was on 4 bands in one weekend including 50 meters. So, yes, definitely you need not worry about having to have a low peak elevation angle! Most people never consider what we call 3dB points in beamwidth also exists in vertical as azimuth directions. Frankly I can’t hardly tell 3 dB difference but 6 dB is detectable. I compare antennas a lot as I use three 20 meter dipoles so I can always have one broadside or almost broadside to the desired direction. QSB and other conditions really can tend to disguise any small difference in antennas! 73 de N4DJ
Another great informative video, I love your full explanations! Thank you. Oh, I'm a VK, so please keep showing the metric conversions for formulas, although I still measure in both metric and feet/inches, as I was born during the conversion in 1966. Cheers Darren VK7daz.....
Well, it 3:42 Am here in the Catskills of NY, 10 degrees Fahrenheit & I can hardly wait for spring. Anyway aside from my 40 - 20 meter mag loop that used 4 inch diameter aluminum tubing I have two Inverted Vs. One is for 40 meters, the other is for 10 meters. Each is very low to the ground with the apex of the 40 meter being 12 feet above dirt. Because of the low-to-the-ground effect of lowering impedance I used the folded dipole method with speaker wire to create both elements of the 40 m V. I like it, its good for reaching as far as Ohio or roughly 600 miles and since DXing is not my interest I don't need a low take off angle. It also does an ok job at listening to 80 meters and I believe also gives me every other harmonic for transmitting provided its in the amateur band. The nice thing about it is, out of it one can always create the fan inverted V by adding pairs of elements which I kind of like over using traped antennas that provide a similar effect. One thing I did notice when using my Nano Vna a week ago for the first time where I did some testing on the 40 m V was while a very deep drop in reflected power occured centered at 7.2 MHz the notch of low reflected power is only 100 KHz to the left or right giving me from 7.1 to 7.3 MHz with a reflected power well below that indicated by a 1.5 reading on an SWR meter. Not exactly sure why the notch is so narrow, but its where I want it. I had other 40 meter inverted Vs & as I remember they had a wider interval of low reflected power. So now to watch the video & see what is offered.
I would take a guess that the narrow bandwidth is not a bad thing. It just indicates you have a relatively high Q and the antenna is efficient on 7.2MHz. I would also take a guess that the higher VSWR at the shack end on 7.1 and 7.3 is due to your feeder acting as an impedance transformer when the impedance at the antenna feedpoint is not 50 Ohms. You might find that adding a few feet of co-ax at the shack end improves VSWR at 7.1 or 7.3 while maintaining low VSWR at 7.2.
The first thing to do is-to insert a line isolator between coax and the VNA. Common mode currents exist even when making measurements and often upset metering.
@@watersstanton thanks for the input, Peter. I'll have to source one. I am looking forward to your experiment using a capacitor part way up the vertical to create a multiband antenna. This project looks really interesting & I'd like to implement the idea my self once the 7 degree Fahrenheit tempertures dissipate.
you can use a reflector lower to the ground to direct the signal a little more and get a little more DB or to make the back a little less sensitive, keep the distance center to center approximately the same as when it hangs behind it at the same height the lower the closer to the base of the mast with director the same principle as tilting a yagi.
A real benefit to me of using an inverted vee is it's omnidirectional, give or take. I use them often when portable and in addition to being much easier to setup than a flat top, I don't have to worry about orientation; I just use whatever is convenient to tie off the ends.
👍Wise words, thanks Peter. EFHW inverted-V is maybe another option if people don't want to run feeder out to and up a mast. It may even allow a lighter mast to be used if not supporting feeder or a choke/BALUN.
That's what I do when I can get up on the mountain and work portable. I use a small diameter cheap and light telescopic pole, and use a thin wire for the EFHW. I have a washer tied in the middle of the EFHW wire and I slip that over the top section of the oole. I can then sit at one end of the antenna. It works very well.
Thanks Peter, I run an inverted V fan dipole on all hf bands except top band (not enough space ) centre height at 30 ft. Sags a lot too due to the weight of the spreaders. Frequently work into SA, NA, NZ, Tasmania and Australia with less than 100W when conditions are good. If you can't hear them you can't work them hi hi, 73 de G4LEN.
I'm planning on an inverted V for an 80 meter INVIS dipole. I found I have the room on the diagonal on my 99x109ft lot with the house ridge in nearly the exact center. I am going to hang the feed point on my dual-band VHF/UHF mast and stay about 2 feet down from the feed point to the J-Pole and still be over 12ft from the ground.
Very interesting discussion about the low angle radiation. I've often wondered what happens to my low angle signal living here in a hollow in Tenessee, USA. I'm basically surrounded by trees, various buildings, and in addition, the entrance to my street is 60 feet higher in elevation than my backyard (garden). So I imagine by the time my signal reaches the end of the street, there's probably not much remaining. In order to get out of my backyard, I suppose an angle of about 30-45 degrees may be the best chance of getting above the trees and clearing the edge of the hollow. And I do know that the trees affect the signal. I work a lot of FT8 and most of my signal reports are -10dB below the signal of the other station in the winter (no leaves on the trees), and almost -20dB in the summer when the trees are fully leafed out, and after a rain. I've tried a lot of different and tennas, and right now my best success has been an Inverted L which in some sense is an Inverted V that has fallen over. :)
Very informative!! Thank you!! But this new guys has a couple of questions... 1. On an inverted dipole where do you measure the above ground dimension? From the peak of the antenna or from one of the bottom legs or possibly half way up a leg? 2. What is considered "ground" when the whole antenna assembly is mounted on the roof of a house with a pitched roof? Say with the peak on a pole at the roof peak and the ends terminating at just about the lower edges of the roof. In essence following the A shape of the roof. Or the the whole assembly on/along the peak of the roof with the center/pole in the center and ends attached near the end peaks.
I've been using an OCFD as an inverted V at about 6m height of the feedpoint. I do pretty well for DX, im going to try a fan dipole in inverted V as the OCFD is very noisy, hopefully it will make some difference.
Peter, I'm a new ham and REALLY appreciate all the information your videos provide in a down to earth way I can understand. Question, you mentioned that a 90 degree apex angle was best for impedance matching on the inverted V, does this apply when using an inverted G5RV Junior antenna? I've seen a couple of articles that state the angle of a G5RV shouldn't be less than 120 degrees to radiate at maximum efficiency. My limited space won't allow for much over 60 degrees. Thanks again,
Excellent. Subscribed. I have a 40m inverted V in a row of trees in my backyard. Feed point is at 18’ and the ends are about 14’. I’m new to ham radio, but I think I’m happy with it. I use WebSDR to hear myself and can routinely get 150 to 1,500 miles out. From the States, I’ve heard myself in Spain and Ireland. And also to New Zealand and Western Australia. All at night, of course. Great information action; much appreciate. One question: would you classify EZNEC as an antenna modeling program that doesn’t effectively model low-angle radiation?
EZNEC is a good program BUT ultra low angle radiation level is largely determined by geographic location and local terrain etc. Something not easily modelled.
ah yes... except not "all": 1885 - Karl Benz invents the first practical motorcar using... metric 1957 - USSR achieves first human space flight using rockets build designed in... metric 1969 - NASA first moon landing using rockets and modules designed and operated in... metric Plus all (or at least most) modern science and medicine uses metric. (maybe you are bating me into this....idk)
@@joelgreaves6728 I stand corrected! But, I should not have said “all” when I meant most. And, to be truthful, what matters is the accuracy of measurement, not the units.
What if you use an EFHW 80M-10M as an inverted V, with the center being a metal mast? How much impact will the metal mast have? How high should the endpoints be?
morning Peter , thanks for posting the video, I recently put up a half size g5rv I made from bits and bobs I had in my workshop, the center point is 32 ft high on a spider pole, its made a big difference on 10.15.20 it wont tune on 40 with the internal atu so i have to use at230, I'm pleased with the results so far, after watched the video I'll see if i can adjust the angle I'm guessing its around the 60deg angle at the mo. I'll try for the elusive 90deg if i can . I'll try it and let you know many thanks..I live in a dip area so losing asl height I would think? many thanks Gw4 mike
I use fiberglass fishing rods to support my elements (14 guage copper thnn/thwn2) with a aluminum mast and tripod 10 meters high. Bluesky mast system Al1
Apologies for the unlinked comment, but would you consider doing a video on shack grounding? It seems a very confusing topic with so many different opinions. Many thanks. Peter M0LMG
Hello, if I want to construct a V Inverted Antenna HF at the rooftop sized 11,5m x 8m, how to construct so that it can have a feed point 90°? My rooftop height from the ground is approximately 12m. I'll wait forward for your reply, thank you.
Another great video Peter. I have often heard it said (and have read on the "wonderful" internet) that it's not good to use a G5RV in an inverted V configuration. I wonder what your thoughts are on that point? I have successfully used inverted V fan diploes so I know that worked for me in practice for sure on those dipoles...
I may try propping mine up at the centre then as it sags quite a lot in the middle, supported at both ends horizontally, as you describe in your video... cheers..
Grate informative video on inverted V’s. I currently have a home brew inverted V fan dipole for 20 and 10m at an approximate height of 20ft with approximately 5 inch separation from the 20m and 10m legs. worked quite a few Dx recently on both bands although I’m picking up a lot of qrm.
Dear sir, thank you for your patient explanations regarding dipoles, radiation, and DX effectiveness. Thank you for speaking to “timing” DX operations - sunset on one side, sunrise on the other side of our (non) flat Earth. In the future, would you please consider addressing the “Delta Loop” antenna(?). From the west side of the Atlantic, 73. KQ4IXD
From someone that has taken HAM thinking - SW Tech thinking - HF Comms thinking and cherry picked. I hate the Inverted V! A true best of both worlds aerial is the Invert L that is 1/4 long in total and bent over at 1/8th wave for the frequency you are on. Obviously in Ham world that isn't one size fits all. But it works WELL for me... I have what is called HF Domestic Licenses here in VK land. The frequencies don't move and I'm allocated on 2325 khz and 4970 khz. Both run 100w. So I'm not interested in pushing it all around the world. But what sort of coverage can I get with my flee power of 100 watts? 2325 khz is going to go further along the ground day and night. It's going to have skywave coverage at night only. 4970 khz is not going to go as far along the ground and will have returning skywave. With the skywave being present at both times, but stonger at night. Everyone here that runs these (on 5 mhz) has started with the Inverted V except me. I watched and waited. They all report a "weird zone" about 80km away where they will totally cancel themselves out of a SDR receiver located in that spot. I laughed.... yep there's your groundwave being cancelled by your "out of phase" skywave returning at night. This is around 8pm local time. They do get reasonable results except for this problem. The next issue is they report poor coverage from 30km away from thier TX site. I tell them all you need to make a decision especially if you only have one frequency. Do you want local or far signal coverage? The two are not mutually exclusive either. If you want local coverage where it stays put day or night (what I call commercial coverage), it's a vertical mounted on the ground over an earth mat. On 5mhz that's not a big pole and it WILL give you the lower take off angle you need for the people far away. IF YOU PUT THE EFFORT INTO THE EARTH MAT! The problem with a vertical is it has a skip zone. Where people just out of the ground wave and not far enough for the first hop get nothing! Now we look at a 1/2 wave dipole.... for 5mhz "the magic height" where 70 ohms gets forced to 50 ohms is 10.2m for 4970 khz.... You don't come any lower than you need for feeding with 50 ohm coax. This "magic height" is just under a 1/4 wave and around this hieght your dipole is working in NVIS like it or not. Lower to the ground it's still in NVIS and your R is dropping and you are wasting power to the ground. Only take what you need here if you want to feed it with coax and a balun (aka Common Mode Choke). IF you are careful with hieghts here, you can get upto 8-9dBi gain straight up! You feed this with open wire feeder you don't need to force 50 ohms & can put it up at the actual freespace hieght. Then deal with the impedance on the ground at the end of the open wire feeder... You get about another 0.5dBi straight up if you do this. NVIS mode.... The tip here is you want as little residual ground wave as possible, so there is nothing to interfere with the 900 km radius that now gets you "to some level". Where as with a vertical the guys in the skip zone missed right out (now they can hear you). The guys local to you will not like this. That's where 2325khz comes in with me. The 50 x 50% Inverted L gives me about 80% performance of a ground mounted 1/4 wave. With respect paid to the skywave at night, I treat these listeners as bonuses. All the time the local guys can leave their radios on day or night and no fuss (unless they are on the fringe of my ground wave). I've seen a little ugliness there. Here the decsion was made a while back to run 50 x 50% Inverted L for 2325 khz as mentioned. With a 1/2 wave Doublet at 10m above the ground & centre fed with open wire feeder. Results came as expected.... Local punters within 120km radius happy.... people in skip zone happy.... people far away actually have the ability to pic which is best and so do the locals if they need to. The important point here is to know I don't change frequencies like International SW services. Nor am I operating across a band like hams are and need the SWR to fit over a band (or 3 etc). This ties in with my first comment about cherry picking from 3 different worlds. The HF comms guy will tell you to run a broadband dipole.... yeah right.... 30% efficent and horizontal when all his cars are vertical whips (i know the ionosphere can invert signal). But really? The key here is I'm on 1 freq - no need for covering all frequencies in how a HF system works. The SW tech will start talking Rhombics and Curtain Arrays and 600 ohm open wire feeders. In actual fact a Rhombic will get you that massive gain in the pointed direction and that low angle you need... But boy do you need real estate! This is all on limited budget and what bang can we get from our 100w? BTW these are licensed for 1kw. But watch out for the power bill! Cheers & 73's from VK2
Good video. I like it when you work in feet
I do too
Oh my word. This guy explains it so well. Im currently studying for my Ham licence and want to start building an inverted V antenna for the 20 band. I have been looking all over the internet for a good exrantion on the inverted V antennad, but this is the best onse so far.
Thanks for that, we have a saying (army signals) 'KISS - Keep It Simple Stupid'.. Being a soldier of course I'm on a budget, so I'm running a Sigma 2011 5/8 CB antenna tuned to 10. A trapped WARC dipole and a Hustler 5BTV.. My sigma is roof height, the WARC dipole is a sloper from the chimney to 10ft above the ground and the Hustler is ground mounted with TWO radials - and I've worked the work (running barefoot too, 100w).. LOVED this video and hope it inspires people who think they can't work DX with modest means, you absolutely can!.
Great to hear. Thanks for sharing.
Excellent points about the over-emphasis on low-angle radiation and the reality of multi-hop in signal propagation in DX work. I have an 80-10m EFHW mounted atop a six foot fence and often work stations over 4000 miles from my QTH running 5w.
Jim - N7RCS
Great to hear from you John. Keep at it. 73 Peter
Awesome Peter! The 40m Invert V was my first antenna back in 1979.
Thanks for sharing.
Thanks, Peter, for another great video and a concise explanation of the inverted vee. I live in the city and originally used a G5RV in an inverted vee. I replaced it with a 65' Windom also in an inverted vee configuration. The apex is about 40' AGL. My angle is close to 90°. I've been happy with my results. I also have a DXcommander Rapide and a Magnetic loop both for 40-10m. I think given the size of my lot that is probably enough antennas. Take care KC8WVG 73
Great to hear from across the pond. 73 Peter.
Excellent video! From my 60 plus years of DXing I can confirm that your are spot on! I typically ( in recent years anyway as I have had the big 4 and 6 element full size arrays) use only dipoles, inverted Vs and sloping dipoles. I prefer the dipoles of course but the inverted V and the sloping dipole work fine when I don’t! I have actually worked over 100 countries over the span of one weekend several times with dipoles no higher than 50 feet. On some occasions in was 100 countries on multiple bands in one weekend. Once it was on 4 bands in one weekend including 50 meters. So, yes, definitely you need not worry about having to have a low peak elevation angle! Most people never consider what we call 3dB points in beamwidth also exists in vertical as azimuth directions. Frankly I can’t hardly tell 3 dB difference but 6 dB is detectable. I compare antennas a lot as I use three 20 meter dipoles so I can always have one broadside or almost broadside to the desired direction. QSB and other conditions really can tend to disguise any small difference in antennas!
73 de N4DJ
Interesting stuff. Great to read and I am sure others will enjoy as well. 73 Peter.
Thank you Peter,
Brilliant run-down on this antenna, this is the first video of yours that I've watched.
73,
Mike ZL3XD.
Thanks Mike, nice to hear from you.
the ionosphere is a leveler of all scores! even a low wire brings some contacts and a lot of fun.
New Ham here. I'm working on my first HF antenna 📡.
Thank you for this very useful information.
73 & cheers.
Have fun!
Another great informative video, I love your full explanations! Thank you.
Oh, I'm a VK, so please keep showing the metric conversions for formulas, although I still measure in both metric and feet/inches, as I was born during the conversion in 1966.
Cheers Darren VK7daz.....
More to come!. Nice to hear from you Darren. 73 Peter
Well, it 3:42 Am here in the Catskills of NY, 10 degrees Fahrenheit & I can hardly wait for spring.
Anyway aside from my 40 - 20 meter mag loop that used 4 inch diameter aluminum tubing I have two Inverted Vs. One is for 40 meters, the other is for 10 meters. Each is very low to the ground with the apex of the 40 meter being 12 feet above dirt.
Because of the low-to-the-ground effect of lowering impedance I used the folded dipole method with speaker wire to create both elements of the 40 m V.
I like it, its good for reaching as far as Ohio or roughly 600 miles and since DXing is not my interest I don't need a low take off angle. It also does an ok job at listening to 80 meters and I believe also gives me every other harmonic for transmitting provided its in the amateur band.
The nice thing about it is, out of it one can always create the fan inverted V by adding pairs of elements which I kind of like over using traped antennas that provide a similar effect.
One thing I did notice when using my Nano Vna a week ago for the first time where I did some testing on the 40 m V was while a very deep drop in reflected power occured centered at 7.2 MHz the notch of low reflected power is only 100 KHz to the left or right giving me from 7.1 to 7.3 MHz with a reflected power well below that indicated by a 1.5 reading on an SWR meter. Not exactly sure why the notch is so narrow, but its where I want it. I had other 40 meter inverted Vs & as I remember they had a wider interval of low reflected power.
So now to watch the video & see what is offered.
I would take a guess that the narrow bandwidth is not a bad thing. It just indicates you have a relatively high Q and the antenna is efficient on 7.2MHz. I would also take a guess that the higher VSWR at the shack end on 7.1 and 7.3 is due to your feeder acting as an impedance transformer when the impedance at the antenna feedpoint is not 50 Ohms. You might find that adding a few feet of co-ax at the shack end improves VSWR at 7.1 or 7.3 while maintaining low VSWR at 7.2.
The first thing to do is-to insert a line isolator between coax and the VNA. Common mode currents exist even when making measurements and often upset metering.
@@Steve-GM0HUU Thanks for the input, Steve.
kc2wvb
@@watersstanton thanks for the input, Peter. I'll have to source one.
I am looking forward to your experiment using a capacitor part way up the vertical to create a multiband antenna. This project looks really interesting & I'd like to implement the idea my self once the 7 degree Fahrenheit tempertures dissipate.
Excellent Peter
thankyou
73
Robert G3RCE
Many thanks. 73 Peter
you can use a reflector lower to the ground to direct the signal a little more and get a little more DB or to make the back a little less sensitive, keep the distance center to center approximately the same as when it hangs behind it at the same height the lower the closer to the base of the mast with director the same principle as tilting a yagi.
A real benefit to me of using an inverted vee is it's omnidirectional, give or take. I use them often when portable and in addition to being much easier to setup than a flat top, I don't have to worry about orientation; I just use whatever is convenient to tie off the ends.
Thanks for sharing.
👍Wise words, thanks Peter. EFHW inverted-V is maybe another option if people don't want to run feeder out to and up a mast. It may even allow a lighter mast to be used if not supporting feeder or a choke/BALUN.
Thanks for sharing.
That's what I do when I can get up on the mountain and work portable. I use a small diameter cheap and light telescopic pole, and use a thin wire for the EFHW. I have a washer tied in the middle of the EFHW wire and I slip that over the top section of the oole. I can then sit at one end of the antenna. It works very well.
Thanks Peter, I run an inverted V fan dipole on all hf bands except top band (not enough space ) centre height at 30 ft. Sags a lot too due to the weight of the spreaders. Frequently work into SA, NA, NZ, Tasmania and Australia with less than 100W when conditions are good. If you can't hear them you can't work them hi hi, 73 de G4LEN.
Great to hear your results. Keep at it. 73 Peter
Big fan of the ‘inverted v’ dipole. Been running a fan dipole for many years.
Thanks for sharing. 73 Peter
Great video... very informative and objective!!
Many thanks.
I'm planning on an inverted V for an 80 meter INVIS dipole. I found I have the room on the diagonal on my 99x109ft lot with the house ridge in nearly the exact center. I am going to hang the feed point on my dual-band VHF/UHF mast and stay about 2 feet down from the feed point to the J-Pole and still be over 12ft from the ground.
Sounds a great plan. Have fun.
Very interesting discussion about the low angle radiation. I've often wondered what happens to my low angle signal living here in a hollow in Tenessee, USA. I'm basically surrounded by trees, various buildings, and in addition, the entrance to my street is 60 feet higher in elevation than my backyard (garden). So I imagine by the time my signal reaches the end of the street, there's probably not much remaining. In order to get out of my backyard, I suppose an angle of about 30-45 degrees may be the best chance of getting above the trees and clearing the edge of the hollow.
And I do know that the trees affect the signal. I work a lot of FT8 and most of my signal reports are -10dB below the signal of the other station in the winter (no leaves on the trees), and almost -20dB in the summer when the trees are fully leafed out, and after a rain.
I've tried a lot of different and tennas, and right now my best success has been an Inverted L which in some sense is an Inverted V that has fallen over. :)
Many thanks for sharing. I have more coming on this sunject.
Very informative!! Thank you!! But this new guys has a couple of questions... 1. On an inverted dipole where do you measure the above ground dimension? From the peak of the antenna or from one of the bottom legs or possibly half way up a leg? 2. What is considered "ground" when the whole antenna assembly is mounted on the roof of a house with a pitched roof? Say with the peak on a pole at the roof peak and the ends terminating at just about the lower edges of the roof. In essence following the A shape of the roof. Or the the whole assembly on/along the peak of the roof with the center/pole in the center and ends attached near the end peaks.
Measure at centre of antenna.
I've been using an OCFD as an inverted V at about 6m height of the feedpoint. I do pretty well for DX, im going to try a fan dipole in inverted V as the OCFD is very noisy, hopefully it will make some difference.
Thanks for sharing.
Peter, I'm a new ham and REALLY appreciate all the information your videos provide in a down to earth way I can understand. Question, you mentioned that a 90 degree apex angle was best for impedance matching on the inverted V, does this apply when using an inverted G5RV Junior antenna? I've seen a couple of articles that state the angle of a G5RV shouldn't be less than 120 degrees to radiate at maximum efficiency. My limited space won't allow for much over 60 degrees. Thanks again,
Excellent. Subscribed. I have a 40m inverted V in a row of trees in my backyard. Feed point is at 18’ and the ends are about 14’. I’m new to ham radio, but I think I’m happy with it. I use WebSDR to hear myself and can routinely get 150 to 1,500 miles out. From the States, I’ve heard myself in Spain and Ireland. And also to New Zealand and Western Australia. All at night, of course.
Great information action; much appreciate. One question: would you classify EZNEC as an antenna modeling program that doesn’t effectively model low-angle radiation?
All modelling software struggles with very low angle radiation because it knows nothing about your location - trees, houses, large buildings etc.
Thank you for all your videos. In this one you mentioned about height above ground - ideal being 1/2. Does the same apply to EFHW?
Thank you for “working in feet.” It’s what the civilized world used to create all the significant technological advances.
EZNEC is a good program BUT ultra low angle radiation level is largely determined by geographic location and local terrain etc. Something not easily modelled.
ah yes... except not "all":
1885 - Karl Benz invents the first practical motorcar using... metric
1957 - USSR achieves first human space flight using rockets build designed in... metric
1969 - NASA first moon landing using rockets and modules designed and operated in... metric
Plus all (or at least most) modern science and medicine uses metric.
(maybe you are bating me into this....idk)
@@joelgreaves6728 I stand corrected!
But, I should not have said “all” when I meant most. And, to be truthful, what matters is the accuracy of measurement, not the units.
What if you use an EFHW 80M-10M as an inverted V, with the center being a metal mast? How much impact will the metal mast have? How high should the endpoints be?
No problem. Ends about 5ft minimum
morning Peter , thanks for posting the video, I recently put up a half size g5rv I made from bits and bobs I had in my workshop, the center point is 32 ft high on a spider pole, its made a big difference on 10.15.20 it wont tune on 40 with the internal atu so i have to use at230, I'm pleased with the results so far, after watched the video I'll see if i can adjust the angle I'm guessing its around the 60deg angle at the mo. I'll try for the elusive 90deg if i can . I'll try it and let you know many thanks..I live in a dip area so losing asl height I would think? many thanks Gw4 mike
Try making the coax lead a bit longer - say add 5m and then check 40m. Let me know if that worjs,
I use fiberglass fishing rods to support my elements (14 guage copper thnn/thwn2) with a aluminum mast and tripod 10 meters high. Bluesky mast system Al1
Great tip!
Apologies for the unlinked comment, but would you consider doing a video on shack grounding? It seems a very confusing topic with so many different opinions. Many thanks. Peter M0LMG
OK will put it on the list
Look forward to this one peter:)
So if im getting this correctly, an inverted V can be resonant and impedance matched. Sounds like a win/win.
It’s a dipole.
Hello, if I want to construct a V Inverted Antenna HF at the rooftop sized 11,5m x 8m, how to construct so that it can have a feed point 90°? My rooftop height from the ground is approximately 12m. I'll wait forward for your reply, thank you.
Don't worry about 90 degrees, just get it up as best you can.The angle is not that important.
Oh I see, by the way my antenna is 70 mega Hertz. So my rooftop is too small to stretch the antenna maximal. Thankyou
Are V or straight dipoles omnidirectional?
Bi-directional, although there is always a certain amount of energy radiated in other directions.
@@watersstanton I live in Calgary Canada. Would you mount the antenna north to south or east to west? I am presently running east to west.
Tnx
Another great video Peter. I have often heard it said (and have read on the "wonderful" internet) that it's not good to use a G5RV in an inverted V configuration. I wonder what your thoughts are on that point? I have successfully used inverted V fan diploes so I know that worked for me in practice for sure on those dipoles...
I can’t think of any reason why a G5RV should not work in inverted configuration. 73 Peter.
I may try propping mine up at the centre then as it sags quite a lot in the middle, supported at both ends horizontally, as you describe in your video... cheers..
Grate informative video on inverted V’s. I currently have a home brew inverted V fan dipole for 20 and 10m at an approximate height of 20ft with approximately 5 inch separation from the 20m and 10m legs. worked quite a few Dx recently on both bands although I’m picking up a lot of qrm.
Dear sir, thank you for your patient explanations regarding dipoles, radiation, and DX effectiveness. Thank you for speaking to “timing” DX operations - sunset on one side, sunrise on the other side of our (non) flat Earth. In the future, would you please consider addressing the “Delta Loop” antenna(?). From the west side of the Atlantic, 73. KQ4IXD
Great to hear from you. Thanks for sharing. 73 Peter
From someone that has taken HAM thinking - SW Tech thinking - HF Comms thinking and cherry picked. I hate the Inverted V!
A true best of both worlds aerial is the Invert L that is 1/4 long in total and bent over at 1/8th wave for the frequency you are on. Obviously in Ham world that isn't one size fits all. But it works WELL for me...
I have what is called HF Domestic Licenses here in VK land. The frequencies don't move and I'm allocated on 2325 khz and 4970 khz. Both run 100w. So I'm not interested in pushing it all around the world. But what sort of coverage can I get with my flee power of 100 watts? 2325 khz is going to go further along the ground day and night. It's going to have skywave coverage at night only. 4970 khz is not going to go as far along the ground and will have returning skywave. With the skywave being present at both times, but stonger at night.
Everyone here that runs these (on 5 mhz) has started with the Inverted V except me. I watched and waited. They all report a "weird zone" about 80km away where they will totally cancel themselves out of a SDR receiver located in that spot. I laughed.... yep there's your groundwave being cancelled by your "out of phase" skywave returning at night. This is around 8pm local time. They do get reasonable results except for this problem. The next issue is they report poor coverage from 30km away from thier TX site.
I tell them all you need to make a decision especially if you only have one frequency. Do you want local or far signal coverage? The two are not mutually exclusive either. If you want local coverage where it stays put day or night (what I call commercial coverage), it's a vertical mounted on the ground over an earth mat. On 5mhz that's not a big pole and it WILL give you the lower take off angle you need for the people far away. IF YOU PUT THE EFFORT INTO THE EARTH MAT! The problem with a vertical is it has a skip zone. Where people just out of the ground wave and not far enough for the first hop get nothing!
Now we look at a 1/2 wave dipole.... for 5mhz "the magic height" where 70 ohms gets forced to 50 ohms is 10.2m for 4970 khz.... You don't come any lower than you need for feeding with 50 ohm coax. This "magic height" is just under a 1/4 wave and around this hieght your dipole is working in NVIS like it or not. Lower to the ground it's still in NVIS and your R is dropping and you are wasting power to the ground. Only take what you need here if you want to feed it with coax and a balun (aka Common Mode Choke). IF you are careful with hieghts here, you can get upto 8-9dBi gain straight up! You feed this with open wire feeder you don't need to force 50 ohms & can put it up at the actual freespace hieght. Then deal with the impedance on the ground at the end of the open wire feeder... You get about another 0.5dBi straight up if you do this.
NVIS mode.... The tip here is you want as little residual ground wave as possible, so there is nothing to interfere with the 900 km radius that now gets you "to some level". Where as with a vertical the guys in the skip zone missed right out (now they can hear you). The guys local to you will not like this. That's where 2325khz comes in with me. The 50 x 50% Inverted L gives me about 80% performance of a ground mounted 1/4 wave. With respect paid to the skywave at night, I treat these listeners as bonuses. All the time the local guys can leave their radios on day or night and no fuss (unless they are on the fringe of my ground wave). I've seen a little ugliness there.
Here the decsion was made a while back to run 50 x 50% Inverted L for 2325 khz as mentioned. With a 1/2 wave Doublet at 10m above the ground & centre fed with open wire feeder. Results came as expected.... Local punters within 120km radius happy.... people in skip zone happy.... people far away actually have the ability to pic which is best and so do the locals if they need to.
The important point here is to know I don't change frequencies like International SW services. Nor am I operating across a band like hams are and need the SWR to fit over a band (or 3 etc). This ties in with my first comment about cherry picking from 3 different worlds. The HF comms guy will tell you to run a broadband dipole.... yeah right.... 30% efficent and horizontal when all his cars are vertical whips (i know the ionosphere can invert signal). But really? The key here is I'm on 1 freq - no need for covering all frequencies in how a HF system works. The SW tech will start talking Rhombics and Curtain Arrays and 600 ohm open wire feeders. In actual fact a Rhombic will get you that massive gain in the pointed direction and that low angle you need... But boy do you need real estate! This is all on limited budget and what bang can we get from our 100w? BTW these are licensed for 1kw. But watch out for the power bill!
Cheers & 73's from VK2
Inverted V dipole is what happens when you don't have enough tall supports. Like mine.
468 mhz is uhf freq. not hf. for hf freq is 300 / the freq.
Whoever told you that!
Coax windings cost far too much, and are heavy as heck.
Is that gold plated coax!
First
W3BEW. Thx for breaking down the workings of this antenna.😊
No problem 👍