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General Category => General Radio Discussion => Topic started by: trenchcoat on December 11, 2018, 1506 UTC

Title: Resource Advice
Post by: trenchcoat on December 11, 2018, 1506 UTC
Hey y'all,
So I am looking to get into creating my own antenna and I was wondering if anyone had any recommendations for resources that I could use to read up on or look at that would help me learn how to create an antenna. Anything helps, even little pointers from your own experiences.
Thanks In Advanced
Title: Re: Resource Advice
Post by: Sealord on December 11, 2018, 1644 UTC
Look around in the Equipment section on this website under Technical Topics; plenty of good info there.
Title: Re: Resource Advice
Post by: Josh on December 11, 2018, 1954 UTC
http://hamradio.tomsk.ru/wp-content/uploads/ARRL_Basic_Antennas.pdf

http://www.ce5prd.cl/documentos/antenna_handbook/00.pdf
Title: Re: Resource Advice
Post by: Stretchyman on December 11, 2018, 2007 UTC
Stick to using a dipole, a no nonsense easy to construct antenna. Beyond that I'd go for a delta loop or vertical. Really depends on how much room you have?

I'd invest in a cheap analyser and learn how to use it. Really good thing is there's lots of SDRs around to compare your signal if you're Txing.

Beverages are good to if you have the room.

Dipole, did I say that already!?

You haven't said if it for Rx or Tx?

Str.
Title: Re: Resource Advice
Post by: ChrisSmolinski on December 11, 2018, 2101 UTC
As Stretchy said, a dipole is a good starting point, and an excellent antenna if you're mostly interested in one band.  Then consider some more elaborate antenna styles.

I've been experimenting with a LoG, Loop on Ground, antenna recently. So far the results are encouraging.
Title: Re: Resource Advice
Post by: trenchcoat on December 11, 2018, 2103 UTC
I would like to use it for Rx and Tx and I have a good bit of room for construction of a large antenna.
Title: Re: Resource Advice
Post by: ThElectriCat on December 11, 2018, 2347 UTC
I agree with Strechyman, A dipole is the way to go (if you want HF). I prefer a vertical for transmitting only, but a dipole will be the best all around performer for TX and RX together. Just like how a socket wrench will outperform vice grips, a single band dipole will outperform a multiband one (primarily on TX) so if You are interested in a specific band, build that antenna first, then move on to other bands later. Best of luck!
Title: Re: Resource Advice
Post by: kris on December 12, 2018, 0047 UTC
Well, you have many dilemmas to resolve. What is good for TX may not be the best for reception (noise, directionality).
 In this forum we take the reception - read what Chris wrote about his antennas. He knows perfectly well what is the best (I congratulate you on your work !!!!). https://www.hfunderground.com/board/index.php/topic,47530.0.html
You must accept a compromise. I would do Sky Loop for listening, and for TX multi band vertical antenna.
http://www.pa1m.nl/pa1m/multiband-wire-vertical/
    Such a set should satisfy you for a longer period of gaining experience.
Or maybe the T2FD antenna will start and you will have both functions in one?
Good luck!
Title: Re: Resource Advice
Post by: ChrisSmolinski on December 12, 2018, 1046 UTC
I would like to use it for Rx and Tx and I have a good bit of room for construction of a large antenna.

I use my 670 ft sky loop for transmitting as well a listening. It's fed with a 4:1 balun and 75 ohm RG-6 coax.  With a tuner I can load it up on 160, 80, and 40 meters nicely. I think I even tried 60m once, just to see if I could get an acceptable SWR. It doesn't do well on 30m and up, most likely since it is many wavelengths in size. A smaller one would probably do well on the higher bands, potentially sacrificing performance on 160m 
Title: Re: Resource Advice
Post by: Rob. on December 12, 2018, 1100 UTC
I'll add to the ten people, eleven pieces of advice.   :)

I use this off center fed multiband dipole for both TX and RX. I am very pleased with the performance. I can use it on nearly all ham bands without a tuner and it is installed at about 65ft above ground. The website sells a commercial version but also shows you how to make one.

https://bit.ly/2Eqfn1q

This the antenna used on my KiwiSDR: http://sigmasdr.ddns.net:8073
Title: Re: Resource Advice
Post by: moof on December 14, 2018, 2241 UTC
Simple dipole, pretty much any type of copper wire.  Inverted v at least 20 feet up at the center.  Ends off the ground.  Start with a bit too much wire and twist in the ends a bit at a time and check with swr meter if transmitting.  If receiving then no need to get it within inches of good swr.  Yeah drawback is transmitting you need to pick a small frequency range you want it to behave well on.  Ya prolly got the shit laying around to build an almost free one.  Chunk of coax going to center was ever my only real cost.  You can leave extra wire on the ends twisted inward if you want to ever go down lower in freq.  Easier to chop off wire than add some if you are off resonance a bit.