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 MMANA-GAL help needed 
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Post MMANA-GAL help needed
Any guys on here with good experience using MMANA. I have got a 5band quad assembled, the results are good but im curious how the optimize procedure works, at least I cant get it to do what I want.

The geometry is 10 simple loops at 2.5m boom spacing. I want to optimize 2 elements DE & RE for each band whilst looking at the rest.

Anyone got time and able to assist email me 2e0ymt@gmail.com

Cheers, Paul


Thu Aug 03, 2017 9:08 am
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 MMANA-GAL help needed 
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Post Re: MMANA-GAL help needed
I hope anyone who replies, replies on here, there will be others also interested.

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Thu Aug 03, 2017 12:17 pm
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 MMANA-GAL help needed 
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Post Re: MMANA-GAL help needed
im guessing nobody uses mmana :blink:


Thu Aug 10, 2017 10:08 pm
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Post Re: MMANA-GAL help needed
PaulGB wrote:
im guessing nobody uses mmana :blink:


I think you will find they do, but optimising a Yagi, where each element is made up of one wire, is going to be a bit different to a quad where each element is made up of four wires.

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Thu Aug 10, 2017 10:45 pm
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 MMANA-GAL help needed 
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Post Re: MMANA-GAL help needed
Paul I had a go at responding to this when first posted, but found it a wee bit too difficult to explain and gave up in the hope someone else would come along.

In essence, the way to do this is to run several instances of MMANA, one with each pair of elements and another the composite antenna with all elements. Optimise one pair of elements, in its own instance of MMANA and manually import the new measurements to the composite antenna, whereby you will be able to see the difference on the other bands. It's not a straight forward job.

The simplest way to optimise any loop, is to add all elements, then remove those for Int. (spacing) leaving behind the elements you want to optimise.

Optimising everything at once is a major chore on a 5 band Quad, it takes a chunk of time to compute (even on my i7, 4.2GHz, with 32Gb RAM), and it doesn't work too well as you can only have one target frequency at a time.


Fri Aug 11, 2017 9:55 am
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 MMANA-GAL help needed 
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Post Re: MMANA-GAL help needed
Thanks guys for the replies.

My first quad 5band was a traditional boom type planar getup, the plots suggests its a winner and has a very tolerant impedance on all 5 bands (10 being the hardest to get right). I tuned this going back and forth thru the bands until I squeezed what I could but being quad loops it was easy by modifying the perimeter table.

I might add nothing has been built yet but mechanically I have it all designed on cad.

My other issue is feeding it (not one for this thread...right can of worms) so I decided to try bringing the DRV to whats close to being the same point. The plan here is to use a balun with one feeder...I have a feeling my first design will be hard to beat as im struggling somewhat to achieve the same gain & f/b. Having the odd shape driven element means I have to use my cad program in combination with MMANA to tune each loop with any kind of speed...hence my question to try optimize.

I will try optimizing a pair and dragging the data into the composite file...will let you know thank you !!

73


Fri Aug 11, 2017 2:29 pm
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Post Re: MMANA-GAL help needed
I have been using MMANA for years, but I must admit the optimisation is a puzzle, I could never work it out, I thought it was just me.

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Fri Aug 11, 2017 8:45 pm
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Post Re: MMANA-GAL help needed
I've found that the simplest way to get optimise to work, is to ensure that the feed point is on a short element all of its own. For example, modelling a dipole, requires three elements with the feedpoint annotated as w2c. It behaves much more predictably after this.

My biggest bugbear with MMANA is that when you do an optimise, there's no easy way to return to the exisiting dimensions without a reload.


Sat Aug 12, 2017 8:12 pm
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 MMANA-GAL help needed 
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Post Re: MMANA-GAL help needed
Just to conclude I tried your method Jason, it helped but not as much as you would expect. It certainly gets you closer but it's still a major headache with 5 bands.

Thanks for pointers everyone, I hope to have something made and tested in 3-4weeks.

73 Paul


Wed Aug 16, 2017 3:03 pm
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Post Re: MMANA-GAL help needed
Hi Paul,

Happy to try and help out fella. Would be curious if there's other software that can pull off this chore simply. Do let me know if you find something.

Also interested ot hear how you get on with the antenna in the real-world.

73 de GM7VSB


Thu Aug 17, 2017 11:37 pm
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