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 owl 3 element on 4mtrs 
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Post owl 3 element on 4mtrs
Is anyone using one and what do you think ??

http://www.innovantennas.com/antennas-a ... egory_id=2


Tue Nov 12, 2013 11:22 pm
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
£60.The trade price on a general broadcast 3 ele is about a £5 to £10......From what I can see the elements on that aerial only want modding a bit.?? Worth a thought.


Wed Nov 13, 2013 9:36 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
M0RKX uses one for portable work.
He seems to do quite well.

A good place to look at what antennas are in use is the list of UKAC claimed scores.

It seems to be very small, and portable, so should be ideal for that, or just getting started.
Obviously, it would normally be horizontally polarised.

If you want to construct one you are better off starting from scratch as broadcast antenna elements would be too short, and of poor quality.

There are construction details of some antennas here. http://www.g0ksc.co.uk/

Cheers

Tony

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Wed Nov 13, 2013 10:23 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
G0CRB wrote:
£60.The trade price on a general broadcast 3 ele is about a £5 to £10......From what I can see the elements on that aerial only want modding a bit.?? Worth a thought.



I have the materials to make one some nice plastic coated alloy just need size details or am I missing some think when I read zbout them


Wed Nov 13, 2013 7:45 pm
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 owl 3 element on 4mtrs 
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Quote:
I have the materials to make one some nice plastic coated alloy just need size details or am I missing something



the plastic coated alloy will alter the dimensions best follow the instructions to the letter or it may perform well below the specification given and may pose problems getting it to tune

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Wed Nov 13, 2013 8:41 pm
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
'Designed with the very latest modelling software packages costing £10's thousands of pounds'
It's just a bloody 3 element beam...or am I missing something?

Peter.

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Wed Nov 13, 2013 10:07 pm
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
G4WLI wrote:
'Designed with the very latest modelling software packages costing £10's thousands of pounds'
It's just a bloody 3 element beam...or am I missing something?

Peter.

Yes, I suspect you are.
But, is it worth bothering about, with a 3 ele?
Probably not.
It will just be the standard spiel for all antennas.
But, you do want every bit of a dB, don't you?

At least he doesn't quote the gain in dB, and claim a junk vertical has 10 dB (whatever that might mean) of gain. :lol:

Cheers

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Wed Nov 13, 2013 10:27 pm
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
G4WLI wrote:
'Designed with the very latest modelling software packages costing £10's thousands of pounds'
It's just a bloody 3 element beam...or am I missing something?

Peter.



Yes, the free and cheap software does not cope well with some designs.

The open sleeve (close coupled resonator) antennas I have built can't be accurately modeled with them, and even NEC4 doesn't cope properly. It is possible to get near, but unless you have spent hundreds of hours experimenting, it is not possible to translate the results into a practical antenna. The dimensions for optimum results are critical to a mm.

The close spaced single band Yagis are better modeled, but not as well as with the proper software.
They are slightly less critical in dimensions, but much more so than a "conventional" Yagi.

If you want it to work to spec, it has to be built to spec.

Also a comment on the prices. This is roughly what it would cost to build the dual band beam I have just built:-

2 X 5m lengths 1/2" tube 8.26
3 X 4m length 3/8" tube 17.28
1 X 4m length 30mm square tube 14.83
ip65 box for balun 6.50
4 X 1/2" element clamps 7.20
4 X 3/8" element clamps 5.28
N type socket 2.50
Stainless bolts and nuts 6.50
Stainless screws 2.50
16 end caps 2.00

shipping 15.00

87.85

That is about £110 less than it would cost to buy it (I think, not certain of the price)

Building at home, it does take a long time.
You need to be able to cut and build within a mm, and be fairly competent generally (ie if you can't drill a hole through a boom at 90deg, or drill patterns of holes on different parts that line up properly, don't start)

Would I build one for someone for £100? A definite no, unless I had a proper workshop set up.
Having the construction set up as in a business is the only way you could make the time spent worthwhile, and I,m sure that people who do it all the time will do a really good job of it.


I admit I am too mean to pay when I can do it myself, but I have all the tools and equipment, and I'm not in a rush.

There is a big difference between being too mean to buy one, and the antenna not being worth the price!

I don't know how mine works yet, but if it works as I expect, I wouldn't hesitate to suggest someone buys one. (Unless of course they feel the same as me and can build one)

And this is scaled down for the 3el Yagi, if you look at the time and work and materials needed, the price suddenly looks different.

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Thu Nov 14, 2013 8:05 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
G3EJS wrote:
G4WLI wrote:
'Designed with the very latest modelling software packages costing £10's thousands of pounds'
It's just a bloody 3 element beam...or am I missing something?

Peter.



Yes, the free and cheap software does not cope well with some designs.

...........The dimensions for optimum results are critical to a mm.

If you want it to work to spec, it has to be built to spec.
...........
And this is scaled down for the 3el Yagi, if you look at the time and work and materials needed, the price suddenly looks different.



It is that critical that even the choice of end plugs can affect the tuning and pattern of the beam, as for cost it depends on how you value your own time and whether you have the tools and the expertise to use them or just want to learn, that's great build one, but if you are hamfisted and "just an operator" you may choose to buy rather than waste the cost of the raw materials and time.

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Thu Nov 14, 2013 8:59 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
Are we not talking about a 3 ele beam for 4 meters thoe ? And not a duel band beam with more elements which would cost more in time and money to make.But to make a 4 meter 3 ele beam aerial you only need some alloy and metal clamp,For a 4 meter 3 ele aerial , 1 round or half inch square boom just a few feet long.And 3 alloy elements just roughly about 3/4 meters,A clamp.One 6 foot X 1 inch alloy pole £3....... Dipole center about £4 clamp about £4 few meters alloy tube.Like I said if you bought say a 3 or 4 element genral broadcast aerial, About a tenner you would have a boom plus the dipole center and the clamp so then just modify the 3 elements.As they sell these at my wholsaler I will sell you as many as you like LOL.Just a thought.Im not trying to be sarcastic honestly just pointing out an alternitive approch.


Thu Nov 14, 2013 9:14 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
G0CRB wrote:
Are we not talking about a 3 ele beam for 4 meters thoe ? And not a duel band beam with more elements which would cost more in time and money to make.But to make a 4 meter 3 ele beam aerial you only need some alloy and metal clamp,For a 4 meter 3 ele aerial , 1 round or half inch square boom just a few feet long.And 3 alloy elements just roughly about 3/4 meters,A clamp.One 6 foot X 1 inch alloy pole £3....... Dipole center about £4 clamp about £4 few meters alloy tube.Like I said if you bought say a 3 or 4 element genral broadcast aerial, About a tenner you would have a boom plus the dipole center and the clamp so then just modify the 3 elements.As they sell these at my wholsaler I will sell you as many as you like LOL.Just a thought.Im not trying to be sarcastic honestly just pointing out an alternitive approch.




I did say "And this is scaled down for the 3el Yagi" :)

Of course the 3el is cheaper and easier to build, but so is the price lower.

That assumes that you can and want to build.

Are the element clamps on the b/c antenna you mention insulated and raised from the boom?
If not how are you going to calculate the boom correction?
Yes, there are standard tables, but how will it effect the performance? On an ordinary Yagi, not much of course, but on this one where a slight change in dimension has a far greater effect you start introducing unknowns, and may well lose the advantages you were looking for.

I'm all for building things, and doing things on the cheap, but you need to do it with the knowledge of how it might effect the end result, and if that effect is acceptable.

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Thu Nov 14, 2013 9:36 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
You can approach this from several directions.

It's just something in the air, for the odd visit to the band, on a limited budget and no real concern for its performance.

Solution - Cobble something together from bits of scrap, using generic dimensions, throw it up with whatever cable there is to hand and be happy you are on the band.

My first 2M antenna was a 4ele Yagi built out of brazing rods, and a piece of wooden batten.
Mounted on a broom stale as a mast. :D
Got me on the air, as a SWL, but a bit worrying as a TX antenna.
Wood isn't an ideal insulator in the UK. :lol:
As a school kid, with just pocket money to spend, it was the obvious, and only, choice.


The I want something reasonable, but I'm not considering the band as important.

Solution - Buy, or build something compact that is accurate and has definable properties.
Use reasonable feeder.

Build if you have time on your hands, the tools to make it accurately and get enjoyment out of mechanical work.
Buy if one or more of the above don't apply.


The I want something that's as good as it gets, this is a primary band, approach.

Solution - The same as above but bigger with the best cable you can afford. :)
If building from scratch be prepared for a lot maths/calculations and time spent getting it just right.

When it comes to building anything the main consideration is time.
As it's limited I have to make choices.
For example.
Do I spend my time building a 4M Yagi, or, do I spend my time operating on 4M, building some equipment.
For me, not building the antenna is the personal choice.

The other way is the financial view.
If an antenna costs £60, and the bits are worth say £20, that's £40 for construction.
Could you earn £40 doing your proper job, more quickly than building the antenna.
Not forgetting any time required to source the parts?

It becomes more biased to the buying choice, as you go up in frequency, where accuracy, and the number of elements increases dramatically.

Obviously there are a lot more factors but, it's a simplistic approach I take with many tasks I have no particular interest in doing.

Since, relatively speaking, commercially available amateur radio equipment is cheap these days the reasons for constructing equipment have changed somewhat.

In the main it's for the enjoyment but there's also the element of either commercially made equipment isn't available, doesn't perform well or, in the case of specialised equipment, is still very expensive.

Cheers

Tony

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Thu Nov 14, 2013 10:35 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
Your all missing the point if i could find the dimensions of it i would build it they tell you sizes for 2 mtr not 4 mtrs and i have limited space as all my beams are in the extension of my loft so think i can turn the 3 elle owl in my loft as its not much big then my hb9cv and it says more gain than it
i have a 5 elle on 2 and 13 elle on 70cm so would like some think with moor gain on 4 mtrs i can put anything up outside as per planning twats the only other way is a scam mast and i am knot paying 475 for one , so that my problem


Fri Nov 15, 2013 7:13 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
g7igc wrote:
Your all missing the point if i could find the dimensions of it i would build it they tell you sizes for 2 mtr not 4 mtrs and i have limited space as all my beams are in the extension of my loft so think i can turn the 3 elle owl in my loft as its not much big then my hb9cv and it says more gain than it
i have a 5 elle on 2 and 13 elle on 70cm so would like some think with moor gain on 4 mtrs i can put anything up outside as per planning twats the only other way is a scam mast and i am knot paying 475 for one , so that my problem

I don't think we are missing the point.
You didn't mention where you are putting it!

Just give Justin a call.
He's a helpful guy.
Tell him your situation and he might have another suggestion.
After all, stuck in a roof space may make a difference.
Some designs are affected much more by close objects.

Cheers

Tony

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Fri Nov 15, 2013 9:11 am
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 owl 3 element on 4mtrs 
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Post Re: owl 3 element on 4mtrs
g7igc wrote:
Your all missing the point if i could find the dimensions of it i would build it they tell you sizes for 2 mtr not 4 mtrs and i have limited space as all my beams are in the extension of my loft so think i can turn the 3 elle owl in my loft as its not much big then my hb9cv and it says more gain than it
i have a 5 elle on 2 and 13 elle on 70cm so would like some think with moor gain on 4 mtrs i can put anything up outside as per planning twats the only other way is a scam mast and i am knot paying 475 for one , so that my problem


Could you not fit the LFA design in your loft?

http://www.g0ksc.co.uk/3el-70.html
its got slightly more gain and i think its 1.4mtrs long
just an idea
Cheers Mark

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Fri Nov 15, 2013 10:08 am
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