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Author Topic: Real time Comparison with HEX Beam and Mono Band Mosley Yagi will be interesting  (Read 73056 times)
W9IQ
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Posts: 1655




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« Reply #75 on: June 06, 2017, 04:55:23 AM »

That is generally correct.

- Glenn W9IQ
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- Glenn W9IQ

I never make a mistake. I thought I did once but I was wrong.
KZ4USA
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Posts: 246




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« Reply #76 on: June 09, 2017, 10:05:02 AM »

Its to bad they are strange looking:)
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KE2TR
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« Reply #77 on: June 09, 2017, 11:58:26 AM »

I find this comparison very interesting as to it was a real a/b test not some modeled software prediction. Back around the late 1990ies I had two 4 element  20 meter antennas  on 30' booms up on a crank up tower, top antenna was at 92' bottom at 40', I could also lower the top antenna to 55' by lowering the tower down. I also had a F12 C3E on another tower at 55' so in between contest I would do comparo's between these different antennas either at the same height or different heights. This is some of what I found at the same height above ground the C3E which is like a two element beam for 20 against the 4 element 20 was maybe 3 db down, the advertised DbD gain was 4.5 on the C3 and 6.6 on the 4 element, remember I said maybe 3db . If I compared the C3 against the lower 20 at 40' there was a very slight difference between the two and the 4 element was always slightly stronger, maybe just in the audio. Now if I compared the top 20 at 92' and the C3 at 55' there was always 6-10 db difference between the 4 element beam and the C3. Now for the ice cream if I ran the stack then it was a bigger spread more like 10 to 15db stronger on the two stacked antennas. I get exactly what NN2X is trying to convey, the cost per DB is insane as two what you have to spend on your install plus the time and effort needed for the up keep and maintenance of a big antenna far compared to the Hex on a simple mast and small rotor. After having owned a fairly competitive station for DX contesting and now not, when storms hit I sleep better at night for not having the biggest lightning rod on the block and keeping it simple gives the hobby a little more of the old school fun.
As far as gain the Hex beam has about the same gain as the normal trapped tri band beam about 3.5db, the forward stacked multi element forward stacked tri banders are about 4.5db and the 3 element monoband beams are between 5.5 to 6db and all these figures are DbD over a dipole at the same height  so you really got to go to better than 5 to 6 elements to get that 3db or better gain.
My hat is off to NN2X's comparo, great stuff!
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ZENKI
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« Reply #78 on: June 09, 2017, 06:17:45 PM »

All with un-calibrated S-meters,  It means nothing in the real world.

If you want to appreciate how hard it is to calibrate and make measurements using antennas read this guide

publications.npl.co.uk/npl_web/pdf/mgpg11.pdf

The National Physics Lab in the UK is one of the most respected calibrated labs in the world. When you understand how hard it is characterize HF antennas on a test range you will soon understand why most ham radio measurements  have little value when the very instrument that they are using does not even come close to being able to make a measurement with accuracy.

Nobody would buy or use a multi-meter with 200% inaccuracy to make voltage comparisons, yet we throw Db's and S-units  around like we have 1 db certainty! Even 100,000 dollar spectrum analyzers have uncertainties in their measurement accuracy of 1 to 1.5 db and hams want to use a S-meter and methods with probably 300% errors We are dreaming.

A good SDR like the Perseus and reasonably well calibrated LOOP we could probably measure these antennas accurately if we took care. We need to measure the differents within 1 to 2 wavelengths.

Maybe if we all joined the ARRL we could encourage them to set up a professional calibration test range. If everyone of us gave 100 dollars for building an antenna range we could measure these antennas with 0.5db accuracy. Now this would be an exciting project for ham radio research.

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KE2TR
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« Reply #79 on: June 12, 2017, 10:02:28 AM »

NN2X has a very good point which Zenki fails to be able to read in these posts, a hex beam up around 30-40' costs about $600, even a Yaesu 450 rotor could be had for around $300 plus another 50-65 dollars for lower mast support. Then a slip up Rohn HD mast for under $200 plus maybe another $150 for very good guy rope. Maybe another $200 for rotor cable and good coax so were talking new about $1500 plus installation.
Now lets look at that stack of mono band beams which will run between $1500 to $2000, a HD 2" mast 24' long around $400 and we haven't even considered a tower which in this case lets say Rohn 45 at north of $200 for each 10' section so lets say between $1500 to $2000 for the tower/guys and hardware needed plus between $600 to $800 for a rotor to turn these antennas. Plus cables and if you cannot install it then were talking another $2000 for install so you have to invest anywhere between $8000 to $10K for w few DB in a pile up. Its the laws of diminishing returns and believe me I had my two tower Stacks of mono band beams years ago, was it nice Hell Yes but was it worth $30-$40K, hell no and I did that system for allot less than the fellows doing it these days.
Having a big antenna system means a few things, one is there is more to break down and fix, two lightning damages go up 10 fold along with storm damages,  You have to be committed or insane to do these things cause it's like racing a fuel drag car or a twin engine speed boat and that takes deep pockets. Sure is nice to have experienced it but I will never do what I did back in the 90ies again.
As far as real gain please read N6BT's array of light which sheds some great info into antenna gain, real gain along with efficiency.
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W9IQ
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Posts: 1655




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« Reply #80 on: June 13, 2017, 08:35:17 AM »

Unfortunately, the hex beam will exhibit no gain over a comparable yagi. So all of the infrastructure comparisons are a wash.

- Glenn W9IQ
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- Glenn W9IQ

I never make a mistake. I thought I did once but I was wrong.
KZ4USA
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Posts: 246




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« Reply #81 on: June 13, 2017, 07:55:33 PM »

NN2X has a very good point which Zenki fails to be able to read in these posts, a hex beam up around 30-40' costs about $600, even a Yaesu 450 rotor could be had for around $300 plus another 50-65 dollars for lower mast support. Then a slip up Rohn HD mast for under $200 plus maybe another $150 for very good guy rope. Maybe another $200 for rotor cable and good coax so were talking new about $1500 plus installation.
Now lets look at that stack of mono band beams which will run between $1500 to $2000, a HD 2" mast 24' long around $400 and we haven't even considered a tower which in this case lets say Rohn 45 at north of $200 for each 10' section so lets say between $1500 to $2000 for the tower/guys and hardware needed plus between $600 to $800 for a rotor to turn these antennas. Plus cables and if you cannot install it then were talking another $2000 for install so you have to invest anywhere between $8000 to $10K for w few DB in a pile up. Its the laws of diminishing returns and believe me I had my two tower Stacks of mono band beams years ago, was it nice Hell Yes but was it worth $30-$40K, hell no and I did that system for allot less than the fellows doing it these days.
Having a big antenna system means a few things, one is there is more to break down and fix, two lightning damages go up 10 fold along with storm damages,  You have to be committed or insane to do these things cause it's like racing a fuel drag car or a twin engine speed boat and that takes deep pockets. Sure is nice to have experienced it but I will never do what I did back in the 90ies again.
As far as real gain please read N6BT's array of light which sheds some great info into antenna gain, real gain along with efficiency.

I think you can build a 2El quad cheap and cover the Hexbeam bands  5 bands no problem and more FB and gain.
Just thinking, they have been around and tested for years. Just saying.
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KE2TR
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Posts: 585




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« Reply #82 on: June 13, 2017, 09:58:07 PM »

The current crop of quads sold on the commercial market are  all the same design, the spacing is set for one band but has you go up the spacing is good for 20&17 but way to wide on 15 and above . The only quad I have seen that really had taken care of that was that Qtenna which was like the old spider quad from Canada but I have not seen any add's anymore for this antenna but each band had excellent spacing.  Were the hex does very well is that each band has decent spacing and there is no need for elaborate matching. Were the quad has its short comings is in the spacing were FB ratio goes down as spacing between the two element increases plus its not a 3 dementional design .
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