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what antenna ?

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Steve, G4WCS

Wed Apr 23 2008, 08:53PM
when I first moved here 15 years ago I put a 2 ele quad on the gable end, which worked fine, but lost the shack when the kids were born, so the quad came down.
Im playing radio again, and until I can sort a beam out, want to put up an omni antenna. I knocked a vertical wire dipole up last weekend to give a few points away for the contest, at the top of a 9m fishing pole but it isnt brilliant.

So the choices are between a J pole or a halo, Ive found an all aluminium halo design on the web, and I think it will look neater up than a J pole, any thoughts on performance comparisons between the two designs ?
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Dai, G8FXM
Thu Apr 24 2008, 10:24AM
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Ever thought of an HB9CV. It doest take up much more room (if ant) that a halo and has some gain and a little directivity. I worked 38 countries with mine, great in the Es season.
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Trev, EA5ISZ
Thu Apr 24 2008, 11:36AM
Trev, EA5ISZ

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Joined: Tue Mar 18 2008, 01:43PM

Posts: 143
I would agree with Dave about the HB9CV. I was going to give you a much fuller reply earlier Steve but have been sidetracked by work! I have never been convinced by the halo in any other use than mobile on 2m. In its heyday on 2m, most of the band users were horizontally polarised and most contacts were either direct or some form of tropo where the polarisation stayed pretty much the same. Under these circumstances, it was sensible to be polarised the same way as your contacts.

6m QSOs, especially from home,are largely via some form of ionospheric propagation mode (Es or F2) or via Aurora or MS etc where the polarisation ofthe received signal is largely unpredictable. The only real advantage of the halo is probably relatively short range contacts with a QSO partner who is horizontally polarised himself. (In my Humble Opinion of course : -)

Having said all of this, there is probably not much to choose between a vertical and a halo. The vertical may well be an improvement especially if it is a collinear arrangement with some gain. Having said that I would still recommend an HB9CV if you can get away with it. With its virtually 90 degree beamwidth it can be left fixed on a bearing of, say, 110 degrees and will cover most of theeuropean Es without having to turn it. Whichever way you choose, good luck. How about a short article on your experiences for Six News later in the year Edited to add, a further advantage of the HB9CV is the ability to make use of the nulls off each side to reduce any local and constant interference you may get with both the halo and the vertical.

[ Edited Thu Apr 24 2008, 11:38AM ]
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Steve, G4WCS
Thu Apr 24 2008, 02:30PM
Steve, G4WCS
Registered Member #283
Joined: Fri Apr 18 2008, 11:55AM

Posts: 70
thanksfor the advice guys - have had a day off work today and scouted all over town for tubing- no joy- all the diy stores have empty racks- and the local stockholder wanted 30 for a 4m length .
Ive got a voucher for a tenner off on ebay so am going to admit homebrew defeat and buy an hb9CV from the chalesantenna man- cant buy the bits for what he is charging !!

longer term im going to use my old mount and rotator that I had up for the quad, and make a 3 ele beam for 6, and mount this and a 9 ele tonna for 2 on the mast, then I can use the HB9CV for hilltop portable use

[ Edited Thu Apr 24 2008, 02:50PM ]
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Stu, MM0BSM
Sun May 11 2008, 01:04PM
Stu, MM0BSM
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Joined: Thu Mar 20 2008, 05:46PM

Posts: 20
Steve try sandpiper for tubing


thats where i buy my stuff from
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Steve, G4WCS
Wed May 28 2008, 09:21PM
Steve, G4WCS
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Joined: Fri Apr 18 2008, 11:55AM

Posts: 70
Ive just spent an hour today putting up a 6m ground plane, mounted at 15 feet above the garage.

Id tried dipoles, and had great success in the openign yesterday- but wanted an interim solution until I can get a beam up.

good swr and picking up GB3BUX no problem- just need the next E's opening now.

Ive also built a high pass filter and braid breaker to put on the input of my TV distrinution amp ( 6 TV's in the house running off it) and can now operate without TVI.
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Brendan, G4DYO
Fri May 30 2008, 07:07AM
Brendan, G4DYO
Registered Member #441
Joined: Sat May 24 2008, 06:56PM

Posts: 42
I'm watching this thread with great interest having only fairly recently come on to 6m. I had a large HF quad many years ago and am convinced that quads are the best antenna but I no longer have a rotator, which is a bit of a problem!! I see that there are commercial half-wave verticals available for 6m and wonder how one of these would perform at 50-60ft. Anyone used one please and will it be effective when the bands really opens in a few years?

Meanwhile I'm continuing to achieve amazing (for me!) results with an old wideband discone. I can't recall the make but it's one of these "20-1000mHz" types which transmits on 6, 2 and 70cms. No single element is more than about 1m long but it sure works for me on 6m with just 100 watts from an FT857.

[ Edited Fri May 30 2008, 06:16PM ]
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Trev, EA5ISZ
Fri May 30 2008, 04:28PM
Trev, EA5ISZ

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Joined: Tue Mar 18 2008, 01:43PM

Posts: 143
Hi Brendan. One of the great things about 6m is that from time to time it is possible to work good distances using either low power, low or no gain aerials or indeed both at the same time. Sporadic E is particularly good for this as the area of strongest propagation between two points is fairly small and tends to move fairly quickly allowing 'small' stations to compete effectively with the big guns.

Once the F2 season kicks in in a couple of years or thereabouts it becomes a different story. The F2 footprint tends to be significantly larger than that provided by Sporadic E and consequently the competition for each QSO ramps up tremendously. To answer your question, yes, the vertical will work on the long haul via F2 but it will take pain and perseverance in order to beat the pile-up. Sporadic E on the other hand will be a comparative pleasure as you have found with your discone.

As a matter of interest, a couple of years ago I played around with the highly controversail EH antenna, mainly on 40m, but I also built one for 6m. It stands some 4 inches (10cm) tall and the diameter of my thumb and was hung in my shack window indoors, fed with 1 metre of coax to the transverter running 5 Watts. I had dozens of Es QSOs within Eu mainly at S9 report levels. The power of Sporadic E
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Brendan, G4DYO
Fri May 30 2008, 06:22PM
Brendan, G4DYO
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Joined: Sat May 24 2008, 06:56PM

Posts: 42
OK Trevor. Many thanks for all that. I used to be very QRV on 10m when I first got my ticket and know how good that band is on the various propagation modes. I shall probably be very frustrated with a vertical and will probably look towards a homebrew quad if I can find a rotor!!

I dipped out on CU2AF this afternoon. He hit S9 at times but he couldn't hear me!

All the best de Bren
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Steve, G4WCS
Mon Jun 02 2008, 12:02PM
Steve, G4WCS
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Joined: Fri Apr 18 2008, 11:55AM

Posts: 70
Hi Brendan.
Over the weekend I have had some really good ontacts into europe on the ground plane. For the time being if your discone is working I would continue to use it until you get something better in the air

On the quad front, mine was built from the info in an old ARRL antenna handbook- I didnt make it tuneable but used +5% on the reflector length. it was a two element- dont know what the gain was but seemed to have a good F/B ratio and a low SWR.

for the spreaders I used 8mm solid fibreglass rods from RS components, Ive no doubt you can now get fishing rod tips or similar . I turned the rotator using a cheap tv type rotator, which performed well.

Ive recently been looking at the various yagi designs available- but of course every design has slightly different element lengths and spacing.

The DK7ZB yagi designs are worth a look- Im either going for the 3 or 4 element 28 ohm versions, the matching mechanism looks better from a mechanical viewpoint than messing about with gamma arms or similar



best regards

steve
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