ULTIMATE SMALL GARDEN 4-BAND HF ANTENNA ? : HAM RADIO
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- Опубліковано 22 сер 2024
- The Half-Square Antenna offers up to 3dB gain on one band. But, Peter G3OJV explains how you can add three more bands.
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Spider Pole I Used
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The metal Spider Mast I use
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Thank you for the information Peter... I followed this and set my EFHW into a half square although I pushed the centre up to around 30ft... This resulted in some excellent improvements on both receive and transmit instantly... As I need to collapse the antenna when not in use I have used 3 poles and it takes around 2mins to get going...I also have an 80m induction coil Insitu and 80m is good too. Thank you again. 😀😀👍
Glad it helped. The original concept suggested that the antenna top section should not be placed too high above the ground - whatever that means! Sounds lime you have got it about right. Good on 80m as well.
Hello peter still useing my half square my friend with the g90 I bought from you a great pairing on 20m band thank you
This is really interesting. My vertical antenna has so much noise it is unusable. I have the balun and wire, so time to give this a try before the weather changes.
Yes give it a try.
Thanks to your explanation I've understood the Half Square a lot better and how it would be an EFHW on 4 bands and will test this when I also replace my doublet to a higher location. I would not have thought of this so thank you! 3dB is significant to get above noise too!
Definitely intriguing, extremely handy to avoid a feedpoint in the middle of the garden...
Thank you Peter for this video. It is intressting the different about noise between this 2 type of antenna ! Vy73 Michael
Yes it was very interesting.
Great video Peter, another vertical antenna that works well on a lot of bands is a DX COMMANDER, have a look 73's
Grounded quaree waves do nor work as well as Ground Planes. Get then off tge ground and you will improve performance. See my recent video.
Peter… you might like to try trapping a couple of sanding blocks between the mast and the ground post… you can then secure with heavy duty tie wraps.. the sanding blocks are made from foam so this allows you to tighten against them… the rough sandpaper surface stops both post and mast from sliding… i have used this technique for static mobile aerial installations with great success..agreed on the half square… lots of bang per buck as they say….. suggest you try the bobtail curtain next…. Another good aerial
Hi, Peter ,Great suggestion , and works great , thanks ,original plan was to be a 20m 3ele wire bobtail , aimed at Asia , using l/c coupler, as un/unbal , not selective enough to keep local interferance out, used verticals 17ft long instead of 16.5 likely due to them being 0.5mm wire hung on fishing line (low profile almost steath )good match on 3 bands (1.6swr on 28mhz) after adding exsisting earth buried radials
which had previously supported a 7mhz ex army vertical in the past(council would go ape ,already have 2masts on site.
Interesting. Thanks for sharing.
Voltage-fed as you used it, the behaviour on the higher frequency bands is interesting. On 15 m the two vertical sections are about 3/4 wave apart and are each about 3/8 wave long but they're fed out of phase on this band so instead of being a broadside array it's end-fire. However on 10 m the vertical sections, each a half-wave long, are about a full wavelength apart and once more are fed in phase so it becomes broadside again. This means you have a "steerable" array but to steer it you change bands!
David VE7EZM and AF7BZ
Try modelling it.
Thank you, perfect! As I have one part of the world I'd like to aim for on 20m and at right angles another part of the world I want to reach on 15m so this is ideal!
Peter... noticed you decoupled the coax with a choke, probably for common mode, but if your gonna use it as a EFHW on the other bands methinks you need a counterpoise...no? A half square is two 1/4 wave verticals fed in phase. As a half square the top phasing line line does not radiate.(much). As the MyAntennas guys have proven, the coax works just fine for a counterpoise.
If you feed a half square at the classic current point, best with a 1:1 balun, it is not a ground mounted 1/4 wave and the feed point may be up in the air 20 or 30'. The radiation pattern angle is more interesting than you might think. Your essentially feeding two phased verticals upside down. Look at a picture of the radiation pattern of a classic 1/4 wave vertical with proper ground radials and then turn it upside down. You may have just bought yourself some more gain for DX because the angle of radiation tends to be a bit lower to the horizon, maybe a db or so but every little bit counts... that's on top of the 3db gain the phased verticals give you. So that's why as you mentioned, some guys claim more than 3 db. The dimensions may be larger or smaller depending on if you use insulated wire or not... Your using insulated wire which has a velocity factor of .95. The lower noise figure...that common mode choke may be the reason.. take it out and see what happens?
Back in the 90's I used a half square on 20; current fed at the top corner, the coax came away opposite or at RIGHT ANGLES, this is really important, at least 15 or 20' and I was always surprised at the good signal reports I got. Note.. believe it or not, you could leave a 49:1 balun hanging in the rain if you had to, I have.. there really isn't much there to break. Look forward to your next video Peter, Big thank YOU.... Richard VA7AA/XE1
It’s a myth. Check out End Fed Zepp.
Very interesting this type of antenna. I am thinking to build a similar one at my Homebase..
HI PETER WOW 30K VIEWS OUR LITTLE HALF SQUARE LOL IT IS SUCH A GREAT ANTENNA G90 STILL DOING YOU PROUD PETER THANKS m7rfs qrp lol great video mate
Hi Mark, yes many thanks. Looking at adding 80m when I get the time. w care. Peter.
yes me to you made the coil look so easy to make thanks vids are great peter
@@watersstanton peter hi feed in the top corner the g90 tunes to 40 15 10 too
Key words to search for that stake holding the mast? I can’t seem to find anything like it on Amazon?
Peter, enjoyed the video as always. You're a wellspring of great ideas! I took your advice from a previous video you posted and built a low profile elevated triband vertical quarter wave antenna for 20, 17 and 15m. Great DX with it and HOA doesn't have a clue! Unfortunately I can't find a way to attach a picture in the comments section.
Fantastic! Great to hear.
Very good video yet again .I will be out putting one up tomorrow I already have an endfed with a 49.1 attached in everyday use I also have a spare 49.1 and will put it up and compare the 2 ..keep em coming Peter 73 john
Many thanks.
What is your comparison results?
@@yurishbox I never got round to doing it I put up a cushcraft 3 element triband instead just keeping my wire antenna for 40 and 80mtr bands 👍
Hey Peter... great video. Could you please share about if you fed this at the voltage point or the "current" point shown on the diagram? Also, if you fed it at the latter point, did your coax feed run down parallel to that vertical element or out perpendicular? Thank you. 73//KK0DJ
I use a Half Square for 20m voltage fed first with 9:1 UnUn which worked well using internal rig autotuner on most bands. Now I use voltage fed with Icom AH4 remote autotuner and extremely please with performance DX on 14mhz and great Australia wide and some DX on 40m. My vertical sections are aluminium tubing base height around 3.9m and using my 9m x 9m I found the same with noise it is the least noise antenna I have installed at this time and an excellent performer on hf bands especially 20m DX and 40m
Very interesting and thanks for sharing. 73 Peter
Your welcome peter thanks again
Great videos Peter, especially your explanation of the Half Square, though I was surprised by your focus on the lower current feed point, with its need for a 49:1 UNUN, whereas the top corner feed point is a direct match for the 50 Ohm Co-ax and when the small connecting box is hung directly from the pole then all the antenna wires are simultaneously supported. Isn't that the connection point of preference?
The bottom point is a voltage point hence the 49:1. The advantage is that it not only works on the design band but also on 40m 15m and 10m.
I am going to put your name up for an Oscar Peter.
Well it would be a great boost for the Hobby!
Nice tip, for siting a spiderpole.👍
Yes, thanks
U have the same problem as i do,my vertical is in a peak of noise but early hours of the mornin i have no noise but i went for a drive with a bloke and usin a radio theres about 20-25m between the noise peaks so it follows the sinewave shape,i added 8 more radials and the noise went down slightly aswell
Interesting.
how long is the radial?
This is interesting. I’m using an 20 metre long EFHW with a home brew 49:1 UNUN. It occurs to me that the Half Square is a EFHW with half it length set out as quarter wave verticals at each end or am I missing something? Is the Half Square going to less noisy than the EFHW which is generally regarded as being a noisy antenna?
There is only one way to find out!
i have the same question?what is your finding?
@@chillychurchil5972 have to admit Ive not had time to change the antenna layout. I think much of the noise I experience is mains born so I have been getting the bits together to build a shack mains filter as designed by GM3SEK. Just need a spare afternoon to build it now.
I can't figure out why the noise is lower just because the noise source is in the lower gain portion of the pattern.
But it is from my findings as well a very quiet excellent performance hf antenna
The signal to noise ratio looks really good on the half square vs the vertical ground plane in end fed configuration. Did you try the current feed point option? I would be Interested to know if it is still lower.
No I sen direct for voltage feed as I wanted the extra bands.
Any of youz used a reflector with this antenna I have more gain east as I have a electric train line to my west ??
Cheers Peter 👍
You are welcome. 73 Peter
This sounds quite interesting. In my situation I think I can get the antenna up about 60 feet above the ground but I'm wondering if that may negatively affect 10 meter. I suppose that since I'm climbing trees I could just hang two antennas if I have to. Any advice on this? Thanks.
Great vic peter thanks m8 👍
No problem 👍
I see you have mounted the balun on an amidon toroid simply wrapping the coax around the ferrite (amidon ft240-43, I guess). Please, does this method provide the same results of a similar balun mounted into a waterproof box? Thanks a lot in advance
Yes it does, maybe even better!
@@watersstanton thanks a lot for you quick reply
Confused. In the video are you at any time demonstrating it as a half square, fed at the upper point or always just as an Efhw in this configuration?
I explained in the video that the antenna can be fed either as a current fed or voltage fed antenna. Either way it functions as a 14MHz half square. The other bands act more like an EFHW.
hi i use it fed top corner 50 ohm its brill
Peter, your diagram shows a ground at your feed point. Did you have a ground spice or was this just showing the screen of the coax?
No I made no ground connection.
Tnx for yet another nice video. 73, Kuba, SP5NZF
Many thanks
Hello peter, always watch your video's really interesting . But, this one I am struggling with the audio. It sounds low and muffled .
I checked it and found no problem..
@@watersstanton Ok Peter Thanks maybe I am just used to the better quality of your other videos. Oh, volume on my computer tv was 39. usually 17
no counterpoise needed? i planned to try these design as i have 4-5m pole at the backyard...
i have 20.04 m of wire for EFHW with 49:1 unun....should i shortened it to 15.3m?
Is the top secret radio Yaesu? fingers crossed for a competitor to the icom 9700
How would it work if fed with twinlead or ladderline?
It would not be mu choice of feeding.
How about showing us a weak dx station and compare signals?
Higher noise on vertical, does it hear better?
Personally I would be more interested in the receive side of things, as opposed to extra 3db on tx..
There were weak signals in the video, any weaker and they would have fallen below the noise.
Thanks Peter, I am definately going to give this a try. If I need to move the resonance up or down, would I adjust the end of one leg and then have to adjust the other leg & the horizontal?. Cheers. Phil M1XCQ
To adjust you should trim both legs equally.
@@watersstanton Thanks Peter!
In current-fed mode, how does it compare to an off centre-fed dipole with the long end turned down? The feed-point is at 25% of total length, so at 20m it serves as a phased 1/4 wave broadside array. (Please correct me if I'm a bit wrong! 🤔)
In theory itis better than a dipole which hs no gain.
So if fed in the upper corner with coax the vertical sections is what radiates not the horizontal? Reason I’m asking is because I have made one in that configuration(mono band) and it is quieter than my end fed.
In a word, yes you are correct.
Some near field cancellation between the two vertical sections?
No they are in-phase
hope your still useing it
Yes I am.
The way you support the fibre-glass mast is "interesting" all right - it's the usual radio-ham-good-at-electronics-but-rubbish-at-engineering botch job, making no account of the bending, crushing or twisting forces on the fibre-glass pole material as it contacts the metal stake. You don't even bother to place some soft material between the metal stake and the f-g pole, and you somehow imagine that the whole setup is a good mechanical solution??? Shakes head and walks away...
Soft material is an absolute no no for antenna masts!
.
@@watersstanton I think the usual response to that kind of statement is "whoosh!" Look it up, if you're interested...
Great video, I'm going to give that a go. I like the support with the fence post driller. 73 de GØUSL
Many thanks