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[ 14 posts ] |
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Choosing a HF Vertical multi band antenna.
M1MPW
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Joined: Sun Nov 04, 2007 7:02 pm Posts: 561 Location: Cambridgeshire
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 Choosing a HF Vertical multi band antenna.
I have a smallish garden, which I have had shortened dipoles strung up before now which worked OK. Since I now have a 12m mast stuck in the middle which is not always up and have expanded my motorcycle parking and other things around it, the placing of a dipole has become a bit of an arse as I've managed several times to get a wire in the face when traversing from one side to the other.
I did try a diy 40m 1/4 wave vertical using a 3m Ali tube and a 7m fishing pole, which was fairly successful, but as it mainly held up with bits of string and clamps, it wasn't too safe.
What I am thinking of doing is just buying a multi band vertical and putting it up in one corner of the garden out of the turning circle of the beams on the mast.
Mainly use 80,40 and 10m , other bands would be nice.
Are there any recommendations, tips or what to avoid?
It would be a permanent installation and any radials would need to be on the ground. ( I can dig them into the soil)
What may be relevant is that my radio room is upstairs and about five or six meters from the possible location of the antenna. (Thinking about near field radiation into the shack.)
Edit: I have looked at the dx commander thing , but it does appear to be for the more temporary setup. I also know to avoid anything with '250' in the model. Mark
_________________ Icom coffee mug. 8 ele TV Ariel. Bluetooth speaker. Technics Amp.
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Sat Jun 04, 2022 8:10 pm |
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Choosing a HF Vertical multi band antenna.
G0JUR
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Joined: Fri Apr 13, 2012 9:20 pm Posts: 3184 Location: Spalding Lincolnshire IO92WT
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 Re: Choosing a HF Vertical multi band antenna.
shunt feeding that mast would get you on some bands
_________________ Neill Its not the class of licence the amateur holds thats important but the class of bias the prat applies to his amplifier
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Sat Jun 04, 2022 9:40 pm |
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Choosing a HF Vertical multi band antenna.
G0KZZ
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Joined: Mon Nov 11, 2013 10:41 pm Posts: 1850 Location: Walsall IO82XN
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 Re: Choosing a HF Vertical multi band antenna.
The higher bands are easily done with vertical antennas, but the lower bands can be a bit more difficult with short (with respect to wavelength) antennas. The efficiency suffers greatly, and the bandwidths can be quite narrow too. Maybe OK for CW only sections, but the phone portions being 150-250kHz wide can be a struggle to cover without retuning the antenna.
If you like the lower bands that much (I do myself!), maybe an inverted-L with an auto-tuner at the feedpoint would be more useful?
If you did want to go down the commercial vertical route then perhaps the Cushcraft or Butternut verticals might be worth a look.They generally have wider bandwidths than some of the smaller verticals. The Diamond CP-6 for example has only about 15kHz BW on 80m! Some of the verticals available may mention 80m coverage, but in reality they can only be tuned over a limited range, and may require additional optional radials to make them work across the full band (again, the Diamond CP-6 does that, with an option radial to allow coverage of the phone section of the 80m band). Examples, Diamond R1 or R2 radials.
Many op's on here will say, "Ah yes, but with my rigs auto ATU I can get full band coverage!". Nope. You can fudge the matching with an auto ATU (actually a variable coupler, it does NOT tune the antenna), but you will find you are losing 80-90% or more of your available transmit power due to large mis-matches on the feeder/antenna. Yes, you will get some power radiated, but far more will simply be lost as heat!
As I used to tell folks that came to the emporium where I worked, sit down with a piece of paper and write down what bands you want the antenna to cover, and what you want to do on those bands, i.e. CW, phone, local/inter-G or DX and so on.
Also, verticals are tuned/fed against ground and/or counterpoise radials. If the ground/counterpoise system is poor then the 'ground' currents will use the feeder outer as a path with the result that the feeder will be radiating pretty well as much RF as the antenna itself, and on receive the outer of the feeder will be acting as part of the antenna system again. Depending upon where the feeder has been run you may end up with really high noise levels on receive.
Hope that ramble makes sense!
73, Mark...
_________________ G-QRP * LIDS * FISTS * SKCC * RSGB
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Sat Jun 04, 2022 9:51 pm |
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Choosing a HF Vertical multi band antenna.
bonehead
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Joined: Mon Jul 28, 2008 12:00 pm Posts: 3051 Location: Warrington-ish......... IO83ql
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 Re: Choosing a HF Vertical multi band antenna.
the Hustler 5 and 6 band verticals are very well built, and will get you on 80, 40, 20, 15 and 10m, with 30m being the bonus on the 6 band version. I use a Butternut HF9V, not as robust as the Hustler, but from 6m to 80m coverage.
both really need radials, the more the better.
_________________ Heil - Icom - Expert - Mosley
from here, to the world.
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Sat Jun 04, 2022 11:11 pm |
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Choosing a HF Vertical multi band antenna.
Sangoma
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Joined: Tue Oct 09, 2012 1:09 pm Posts: 14805 Location: West Midlands
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 Re: Choosing a HF Vertical multi band antenna.
As said, you will need an excellent radial system, especially on 80, and on 40. 20-10 you might get reasonable results. On 12 and 10 (and maybe 15) a CB antenna will outperform multiband verticals unless mounted very high. The CP6 must be the most expensive disappointment I have ever had in radio. I have 2 of them (or the remains of 2 as I have probably taken bits from them over the years) in the garage, and never had any desire to put them up again. Don't think any one ever heard me on 80, and on every band an endfed inverted L worked many times better. These (like a CB antenna with an unun at the bottom) https://www.ebay.co.uk/itm/221688097046 ... XQJ3xRc9cD outperformed the CP6. The CP6 also had mechanical problems requiring the rebuild of one inductor. I bought the CP6 as it does not theoretically need radials, as there is a tuned radial for each band. It was easy to tune for all bands, and looks good Nearly all multiband verticals have the highest frequency part at the bottom, so if the base is 6' off the ground, that is how high your antennas are. Only the lowest frequency uses the top part. I also tried a Sandpiper multiband vertical, worked less well than the CP6, but was less expensive, and much harder to tune. Did work a little better than a 60W lamp on the end of 6' of twin flex, but not by much. A point that may need considering, you say in the corner of your garden, that means there could be 3 other gardens on that corner, is it possible for people in those other gardens to get within about 10' of the antenna? I can see why you want a vertical, but I think you will be disappointed with anything you pay a lot for. If I had a mast, and just wanted something to use while it was down, and it had to be vertical, I would go for a 10-12m fishing rod, with a wire up the middle, fed by an unun at the bottom, couple of short counterpoise wires (length by experiment, as they don't have to be very long or very many) and ferrites that can be positioned along the coax, again by experiment. Simple, cheap and all parts reusable for other projects. If I could then extend the wire out the top to even drape over the roof of the house, it would perform better, when it reaches around 66' it would make a very useable antenna. Another alternative could be a Tarheel or Atas 120 on a pole with a couple of radials First vertical I had was an 18AVQ in about 1983, which worked OK but had quite a few radials, but a long wire or dipoles worked better most of the time on most bands, I've never found any vertical that worked better than that, mostly disappointments.
_________________ Gee Three Eee Jay Ess - RSGB, SARL, EPC
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Sun Jun 05, 2022 4:30 am |
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Choosing a HF Vertical multi band antenna.
g3rfh
Advanced Member
Joined: Thu Jul 23, 2009 3:09 pm Posts: 220 Location: Cleveleys, Blackpool, Lancashire. LOC IO83LV
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 Re: Choosing a HF Vertical multi band antenna.
I have used a GAP Titan DX for many years and found it worked very well on all bands. The base of mine is about 12feet above ground and I guy it about one third from the yop due to the high winds I get being so close to the sea. de Ken G3RFH
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Sun Jun 05, 2022 9:14 am |
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Choosing a HF Vertical multi band antenna.
MI0OIM
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Joined: Wed Oct 03, 2012 9:05 pm Posts: 668 Location: IO74bq South Antrim
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 Re: Choosing a HF Vertical multi band antenna.
I have a Sigma SE X80 with the additional 40/80 expansion kit.
its..... all right.
30 and up I've had plenty of QSOs, but nothing on 60 or 80.
the end fed helical I built with 3 slinkies, a 9:1 unun and a 12m fibreglass fishing pole is MUCH better.....
_________________ http://mi0oim.blogspot.co.uk/
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Sun Jun 05, 2022 9:22 am |
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Choosing a HF Vertical multi band antenna.
M1MPW
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Joined: Sun Nov 04, 2007 7:02 pm Posts: 561 Location: Cambridgeshire
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 Re: Choosing a HF Vertical multi band antenna.
Thanks for the views on verticals etc. My first impulse was for a vertical how ever inefficient it was and so I could just leave it up and have instant access to hf.
The 'corner' of the garden isn't quite the physical corner, so the antenna would still be 3-4m from any public or neighbouring land. Coupling the mast unfortunately isn't going to be great as a) it only goes up when operating 70mhz and above. And b) the sections are not electrically connected. ( it is a 12m SCAM pump up with eight insulated sections.)
A end fed sounds like a good idea, it is an antenna I haven't tried yet. It would mean that the 40m of wire would have to go round the perimeter of the property on the ends of fishing pokes to get the height and it would also have to turn back on itself to cover the distance as the perimeter is only about 30m. The start or end of the halfwave would also have to pass within a meter of my operating desk as it is upstairs.
Anyway, so , maybe I will start by making one. Need to order a few toroids and some new wire.
But, if a cheap vertical comes along I will probably buy it and be disappointed.
Mark
_________________ Icom coffee mug. 8 ele TV Ariel. Bluetooth speaker. Technics Amp.
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Sun Jun 05, 2022 4:39 pm |
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Choosing a HF Vertical multi band antenna.
M0RDI
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Joined: Tue Nov 19, 2013 10:05 am Posts: 2975 Location: Banbury Oxfordshire
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 Re: Choosing a HF Vertical multi band antenna.
Being as though unlike me you have some garden my thoughts are these
Use fiberglass reinforced antenna mounting poles to mount either a 10 metre moxon rectangle or a cobweb in the corner of the garden then use the same mounting pole to support an inverted L using a 9:1 unun at the feedpoint the wire running back towards your roof for the other HF bands If you can bury some counterpoise, this will help
Perhaps if you have a gable end or a chimney that could accommodate another antenna e.g 6/2/70cms ?
you could then use that mounting pole to tie off the end of your inverted L
I hope that helps in some way ,I do not profess to being any kind of expert but it is just a point of view .
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Sun Jun 05, 2022 8:42 pm |
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Choosing a HF Vertical multi band antenna.
ei2glb
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Joined: Thu Jul 26, 2007 3:39 pm Posts: 3006 Location: Kildare IO63MD
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 Re: Choosing a HF Vertical multi band antenna.
Look into a DX Commander vertical, he does a couple of different types, as long as you can get a few radials down you should be good to go
_________________ Trevor EI2GLB QRZ+LOG WX
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Sun Jun 05, 2022 10:20 pm |
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Choosing a HF Vertical multi band antenna.
bonehead
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Joined: Mon Jul 28, 2008 12:00 pm Posts: 3051 Location: Warrington-ish......... IO83ql
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 Re: Choosing a HF Vertical multi band antenna.
M1MPW wrote: I have looked at the dx commander thing , but it does appear to be for the more temporary setup.
Mark
_________________ Heil - Icom - Expert - Mosley
from here, to the world.
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Sun Jun 05, 2022 10:58 pm |
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Choosing a HF Vertical multi band antenna.
G0KZZ
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Joined: Mon Nov 11, 2013 10:41 pm Posts: 1850 Location: Walsall IO82XN
Feedback: 5 (100%)
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 Re: Choosing a HF Vertical multi band antenna.
g3rfh wrote: I have used a GAP Titan DX for many years and found it worked very well on all bands. The base of mine is about 12feet above ground and I guy it about one third from the yop due to the high winds I get being so close to the sea. de Ken G3RFH I've always liked the look of those antennas. I would have purchased one years ago, but my XYL would no doubt have ideas as to where I could install it! 73, Mark...
_________________ G-QRP * LIDS * FISTS * SKCC * RSGB
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Mon Jun 06, 2022 6:30 am |
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Choosing a HF Vertical multi band antenna.
ei2glb
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Joined: Thu Jul 26, 2007 3:39 pm Posts: 3006 Location: Kildare IO63MD
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 Re: Choosing a HF Vertical multi band antenna.
Missed that and mine is up a year and no issues, apart from breaking it with the lawn mower last week but that was my fault bonehead wrote: M1MPW wrote: I have looked at the dx commander thing , but it does appear to be for the more temporary setup.
Mark
_________________ Trevor EI2GLB QRZ+LOG WX
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Mon Jun 06, 2022 10:53 am |
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Choosing a HF Vertical multi band antenna.
G0HVQ
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Joined: Sat Jul 21, 2007 9:30 am Posts: 827 Location: Nr Gloucester / Tewkesbury
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 Re: Choosing a HF Vertical multi band antenna.
M1MPW wrote: But, if a cheap vertical comes along I will probably buy it and be disappointed. Mark Don't write off verticals, some of us have great success with them: I've got a battered old Hustler BTV that I bought second-hand that's been up 17 years, 259 DXCCs worked on both 40m and 80m. As you say, one of the big bonuses is that you have instant access to HF and can just forget about it. As it's a trapped vertical you can tune it to each band to get a low SWR so no need for a tuner. Many commercial verticals cover 40-10m, 80m is the hardest to get. A quarter wave vertical is huge but works well, I've got a top-laded Cushcraft MA8040V which covers 80m and 40m but the usable bandwidth on 80m is only 100kHz due to the loading coli. You can move this segment, so put it either at the CW end or the SSB end of the band, but you can't do it when it's up. Other verticals that have 80m are often a compromise e.g. I think the Hustler 80m add-on is just a loaded whip at the top of the aerial, that doesn't even use the rest of the aerial to radiate. And regarding radials, people can get fixated by the theory - yes verticals should have them, but in my experience I've found they still work without, or with just a few. The more the better if you're looking for DX, but for general use don't worry too much. I'm part of a contest group and we take great trouble to lay out radials on our verts, which gives us the results, but at home I rarely use them. My MA8040V only goes up in winter when there's more darkness for 80m DXing and has never had radials, and I've worked the world with it including many Pacific islands.
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Sat Jun 11, 2022 6:51 am |
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