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Quad GW4CQT for band.
After the recent renewal of my concession, I would like to build an HF antenna. I would like to reach out to everyone with experience for constructive advice. Ideal antenna – invisible multiband. I can think of a quad loop 80m resonating with harmonics excited by a balun 1:4 . I would mechanically do the antenna a bit “composed” – “he squeezed his shoe” to attic the neighbors apartment on the top floor. He doesn't have a problem with that yet. The coaxial drain would be right in my room – hamshacku na 3. in a former school.
I enclose a preview of the attic of the top floor of my house where I still have access.
I would place 1m laminate bars in the corners of the attic, I would stretch the silicone between me and attach the antenna wire to it. The wire is 1.8 mm enamelled.
The problem is not so much the mechanical construction, as if there is a sheet metal around the perimeter of the attic + metal railing = short thread. I could theoretically have a railing somewhere “fick”, that might be possible.
It's about building an invisible multiband antenna, least affected by nearby metal objects. Advise me what you think I should place there, taking into account that I may no longer have access to it.
I will be grateful for any advice.
Ľubo – OM6ADPA loop like this can work, but it has me a few but.
It will not be a delta, ani qad.
You'll have to go some way, when the attic loop will short-circuit in this band, or maybe this is just a band, will radiate well.
Sure is just that, with vodic antenna, to be the fattest, even the older type of coaxial, RG2013, which, thanks to the large diameter of the braid, replaces unsightly AlFe rope, etc..
So that the loop works at least a little optimally and there are not many power losses, ideally to fit the power loops, dialkovy antenna clen SGC.
He works not only as an L member, but for small impedances, as a full-fledged PI article.
I have it tried, but not very verified.
The whole antenna construction may not work satisfactorily in the end, it's short for lottery.
Without more precise measurement and experimentation, no specific conclusion can be made.
The experiment is cheap, only we kind of make money…http://www.sgcworld.com/239ProductPage.html
http://www.sgcworld.com/Publications/Manuals/239man.pdfThere are options in the PDF manual on the last page, how to install not only dipoles, but also loop antennas, for various vehicles and objects.
The loops went well.
To control the SGC 239, nothing is needed, just bring him a 12V supply voltage and it works autonomously.
Probably a loop designed by you, will also work.
Koli nizssim breeds, rent 80m, Is good, make vodic antenna, had the lowest specific resistance, otherwise, countless losses increase and the joy of connection decreases.Otherwise it is likely, that you wouldn't even have to solve the loop, is possible, that if you can find suitable connection points on the attic, using delta power, or gamma, or double gamma, so you get the result without having to pull the loop. Antenna is very helpful, or MFJ analyzer etc..
The problem will be, that all interference, which are in the house, if it is close to the resonance of that antenna, will be transferred to TRX and vice versa, VF sulfur, will crawl around the house..
But you can't avoid it, not even in the construction of that loop, on insulators.
I checked it a year ago, on a shipping container, where using magnetic holders for skiing, I grabbed the PVC pipes from the side and stretched the loop over the container.
But I didn't get much results, because I couldn't do enough.
Happy Christmas!This solution near such massive conductive structures will not be ideal. This is almost better done by the so-called. paddle antennas. The question is also the expected power to the antenna, which then causes TVi interference. Sometimes a more acceptable solution is a regular vertical or one of the variants of an LW antenna with a quality antenna member. There are always some compromises in the housing estate.
Ľubo, put that antenna on, you will be happy with her. SP7LTA specifies the length of the loop
82,84 m, powered by a balun 4:1.
I also have a loop, I use it on all HF bands. On 2 so you won't have to list this 70 cm
it also works. You will be surprised quiet, Net income. you 73! Fairy, OM3CAQ
Tono, I will not see the sketch, reports “Server not found”. But other loop sizes also work: http://otc.cq.sk/index.php?option=com_content&task=view&id=449
All good in a year 2016 … 🙂 Greetings to all, thank you for advice.
I tried the antenna up on the roof and it was “silent”. 84m stacked on a perimeter of 56m… I was really sad about the result, but it was just a test of whether it would work. My previous end-fed 42m dipole went incomparably better. I compared them against each other… At the moment, I have an insulated passage through the bottom wall to the tuner and a 2x41m dipole outside. Invisible 0.3mm lacquered wire thrown into trees. It is rich enough for all bands to receive. Na jar, possibly when I finally buy tcvr, I will try to replace the delta / quad dipole with an anchor anchored in the soaring trees. The height of the ant is and will be about 15-18m above the ground. I guess it'll squirt.
Right now I'm just listening with a cheap SDR.
Anyway, I'll let you know when I go one step further.
73 of OM6ADP
Ľubo
