Spider beam :-(

Hello Andy, as regards the hexbeam they do work better if higher. But my hexbeam works very well at 2.5m AGL which is often at that height as I use a SCAM12 mast and for safety reasons it is lowered/parked at that height overnight. I have a 40-6m vertical and it works well dx but the downside is that it can collect higher levels of noise levels. Horses for courses I suppose…
Mike

I base the statement on experiences of people who travel around the world putting on DXpeditions etc. I know a lot of HF contesters who have abandoned beams unless they can get them 60ft or higher. For less effort directional vertical arrays will kick the backside out of a beam’s pants unless you can get the beam right up high.

Oh that is interesting.

“I base the statement on experiences of people who travel around the world putting on DXpeditions etc.”

Are you able to give an example[s] ?. The reason I ask is because given the circumstances of such adventures there is a normally a mix of antenna.

Mike

Yes indeed… especially when VERY close to the sea. check out this link:

http://www.k2kw.com/tv.html

I have heard these guys many times both here and when living in the US and they were often LOUD…

Also (even better) a vertical dipole array (next to sea water) will knock the socks off a low horizontal yagi in the same spot. Check out some of the recent DXpediton reports in Radcom. So yes, verticals can work VERY well.

73 Marc G0AZS

by the sea hmmmm :smiley:

3 EL Yagi and Vert A99
We called it Tidal dxing or toe dipping in early CB days
Tide in Dx
Very high tide in BIG DX
Tide out NO DX

Best peaks was 1 hour prior and till 1 hr after high tide the higher the tide the better yes yes sitting by the water has a big reflector effect.

Yet remember one day first worked NZ off the portable was on the vertical but following weekend could only do it on the Hoz beam.

But sitting by waters edge and even taking a long wire connect to car and throw in to the sea helped also. Yep had many a happy hour at Adleburgh beach near the tower in Suffolk on the Orford spit especially when the high tide was so high one day you could not drive off the sea wall cause you were cut off water behind and front of me damn fine DXing that 2 hr period I had :smile:

Going have to find me some local coast spots I thinks and do it all again but this time on the Ham bands

Karl

Here’s a few setups from the last 2 years.

FT4TA Tromelin 2014

160m: Vertical with hat built on 18m Spiderbeam pole
80m: 2x phased verticals built on 18m Spiderbeam poles & DVA-80 by DX Engineering
40m: 4 square array built on Spiderbeam 12m poles
30m: 4 square array built on Spiderbeam 12m poles
20m: 2-elements Vertical Dipole Array built on Spiderbeam 12m poles
17m: 2-elements Vertical Dipole Array built on Spiderbeam 12m poles
15m: 2-elements Vertical Dipole Array built on Spiderbeam 12m poles
12m: 2-elements Vertical Dipole Array built on Spiderbeam 12m poles
10m: 2-elements Vertical Dipole Array built on Spiderbeam 12m poles

VK9ML 2014
160/80/40: Battle Creek Special
E/W Beverage
N/S Beverage

80M: Sigma Vertical
40M: 2-element Sigma
30M: Sigma Vertical
20M: Vertical Dipole
17M: Vertical Dipole
17/12M: Duobander yagi
12M: Vertical Dipole
15M: Verticla Dipole
12M: Vertical Dipole
10M: Vertical Dipole
6M: 5 element Yagi

TX5A Clipperton 2013

40m 4-square
30m 4-square
20m 4 ele vertical dipole array
17m 4 ele vertical dipole array
15m 4 ele vertical dipole array
12m 4 ele vertical dipole array
10m 4 ele vertical dipole array

160m 27m high vertical (Titanex V160E)
80m 4-square
40m 4-square
30m 4 ele vertical dipole array
20m 4 ele vertical dipole array
17m 4 ele vertical dipole array
15m 4 ele vertical dipole array
12m 4 ele vertical dipole array
10m 4 ele vertical dipole array
Beverage antenna 30°/210° for receiving on low bands

Certainly VDAs work fabulously by the sea but they still work as good as a beam when the beam is low.

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Hi Mike, and guess what, my Radcom is late AGAIN. There’s something wrong with the RSGB distribution path to Germany. I’ve had to have the RSGB office send me a copy direct, 3 months out of the last 6 after it hasn’t arrived!

In any case, back to Karls antenna, points as I understand it:

  1. he wants multiband - ideally 40m-10m but at least 20m-10m, so resonant verticals, phased or not will not address this need.
  2. he wants to build it himself, not buy an off-the-shelf model.
  3. he wants directivity to null out some of the QRM
  4. it has to fit in his Garden

From all of the options given I think the only one that meets all requirements is the hex beam, which is what Karl is now planning to build.

By the way, the G5RV he has up now, certainly gets out into Europe very well, he managed to work me despite all the contest QRM on both of my summits this morning.

Ed.

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Hi Andy,
I could also add the specs for the antenna we used on the VK9HR Lord Howe Island DXPedition back in 2011 to your list.
The point is it’s always better to use an antenna built for a specific band if you can rather than a multi-band antenna however that’s not practical unless you own a farm or something like that, certainly a lot of space.

Like most of us, Karl doesn’t have space for single antennas for each HF band.

We can all dream though …

Ed.

The G5 is only 22ft by right centre should be double that but one can’t do that here have to be careful with surrounding peoples.

The G5 is strung on one part east west and at centre almost goes off in 90. north south so its L shaped. And It gets me out on air :slight_smile:

Blind spots
From experienced so far say south of Brazil and Asia say Vietnam to HK koreas etc yet Japan not a problem. Australia not to bad North Americas not really a problem. Yet that could just be seasonal as not worked from here during Spring and early summer months. Time will tell but from this old girl she don,'t do to badly sometimes get nicely surprises on where I can reach was hearing China very loudly other day trouble was Contest and 100’s calling back .

Now to build the Hex will give me more directional and null out QRM from other areas and the spider is just to big for here shame really. But antennas certainly can make difference certainly will experiment with verts one day once get a better understand of them its matter trying to get the height on them in me garden is bit restrictive. Mind you could set up a vertical mast that,s nigh on 30ft but make it a temp one so up in use and down when its not permanently there. Must Admit I do like the antenna building of things from me first ones from the Invert centre fed V and the 4EL beam Yagi on 11m had a lot of fun on.

So end of day many thanks for all your feed back and sites to visit and have a look and learn sort of thing and getting back to the original question I am going to build a 1:1 balun for choking purposes to place on the hex.

Cheers and beers folks

Karl

Well if you can’t get to Germany from SW England very well using 10W SSB on 20m or 40m SSB you should give up radio!

Well he probably does. Just not all at the same time.

Hello Karl,

Well there you go , lots of info’ and Ed has done a good summary and others have given examples of what stations use so you takes your choice.

The notion of blind spots is a bit of a myth unless you have a tower block or mountain on your doorstep.

Good luck :sunglasses: and perhaps an update from you? People I think will be interested in how the hexbeam works out for you I think.

Cheers
Mike

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Many DXers do very well from small gardens but I think you will find most use single band antennas.

I would suggest using fishing pole supports and look at dedicated dipoles in verticals, sloping and horizontal configurations. The antenna will be the cheapest possible. Two easy ways I use to get some directivity is to slope a simple dipole towards the DX or use a second ‘behind the first away from the DX’.

Honestly going to be hopeless trying to put up a horizontal polarization multi band beam and expect brilliant results if you cannot even get a G5RV/dipole above 22ft if you got twitchy neighbours about anything at height. I think you might be very disappointed by the return in effort for a hex beam that low down if you plan on trying 20m or below.

A VDA option might work for you, it has diractivity and it is pretty broad, not seen a multi band version but if you willing to experiment you might stumble on some interesting combinations. A VDA isn’t just for right by the sea. I am sure a 17/12 WARC VDA is an option a few might play with.

72

Dom
M1KTA

I tried that suggestion Dom but was told that Karl wants a beam (not by Karl though!) I don’t think he wants a beam but he does want a better antenna than a low G5RV and he doesn’t have a lot of space.

To show how a low beam is not a DX magnet here are 2 plots of a simple monoband 2 ele beam for 20m.

First, in free space, i.e. the theoretical maximum performance.

And here is the same antenna at 6m (about 20ft) above real ground.

You can see the main gain points skywards at 38degs. A cloud warmer.

But, Andy, if you can get the plot of Karl’s G5RV at the height above the ground it currently is, which I don’t know but it seems it’s not much, you’ll probably see that even the “cloud warmer” low yagi will represent a huge improvement with respect to Karl’s current G5RV. Even with a not very high beam he will copy many DX or weak activators which are absolutely not copied at all by the G5RV.
When I had my station in Aranjuez-Madrid, I had a broadband folded dipole as an inverted V hanging from the TOP of my tower with the center at about 14m above the ground and the ends about 5m above ground. Also my 5 elements tribander yagi was on a mast at the top of the tower, let’s say about 15m above the ground.
By switching between these 2 antennas I could several times pass from copying a Northamerican station S9 with the yagi to NOTHING AT ALL but noise on the broadband folded dipole, even being a not very noisy antenna (because it’s deaf ;-)).
I know a well installed G5RV should perform probably better than the deaf folded dipole, particularly on the lower bands, but I’m sure the difference won’t be too much.
In conclusion: I’d say: go Karl and get your beam installed as soon as you can. Heaven will open for you as soon as you tune the bands.
Best 73 de Guru.

There’s lots of truth in what you write Guru. The point I was trying to make and reinforced by a few others is that IF you do not have too much space AND neighbours who don’t think beams are sexy AND you cannot raise your beam very high THEN for less effort and cost you could try some of the other ideas which can be made simply and cheaply.

15m is probably twice as high as likely in this case and when you run the same simulation the angle drops by 1/2 to 19degs which is starting to be useful.

Karl is a foundation licencee and having been there as well (was M3KTA) you do latch onto the idea that a beam antenna is the only option to give you better directional signals RX and TX… but you have to think how that will work if he cannot get it up high enough and is it the best option?

I will say as I am sure many realise that a G5RV IS NOT a multiband antenna although loads use it as one with a tuner. This is a really bad idea as you will loose much of the rigs power in the tuner. Karl would do far better with mono band dipoles. Which is what a beam is … a hex beam is nested bent dipoles with a bent reflector. However stil far better to use vertical GP or vertical dipoles though if Karl cannot get the beam at height (said he cannot get above 22ft which is only just 7m so 15m would not be possible) BTW I note you are in Saltash… not exactly a million miles from loads of possible decent /P beaches (I know the place as was at school in Plymouth and grew up in Cornwall and I have used them) where a vertical GP or vertical dipole, vertical moxon, VDA on the shore would probably out perform anything you might manage to put up at his QTHr. If you is down near the sea in Saltash not surprised few NA signals you will have a lot of higher land immediately behind him too. Better to operate /P and find a better location with decent take off in that direction…

If you remain at home invest in plenty of radials, some resonant and put up some verticals. Some of the biggest signals you will hear these days are from using verticals not beams as have already been written about. You would think someone spending that much on a trip would investigate what the best antenna would be?

10W SSB is qrp and Karl you need to use the little grey cells and not just throw up an antenna in theory that works but that might not help that much. I’ve run contacts to VK/ZL with less power on SSB using a simple vertical dipole at the shore line, you have to get YOUR antenna right and I would be extremely surprised with a low hex beam.

I’d compare a mono band dipole with your G5RV setup and see the difference BEFORE you mess about building a hex beam.

BTW think how the neighbours will react to a rotary washing line at 30 feet and then think is it worth trying to put up a hex beam as that is what they will look like to a non radio amateur.

72

Dom
M1KTA