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Hello,
I would need advice on building an ant, respectively what ant. I found a lot of antennas but I don't have much time to experiment with my work, so I would like to build something that works, ideal for the first shot.
Ant should be on 80m. It can also be multi-band, but mainly 80 will be used. Well, it would be best if it were something vertical. Ant will be in the cottage with the A-shaped roof. I was also thinking about the solution of building a vertical on the ground, but again it is a problem to make radials since I don't have such a plot of land. And in addition, make an ant before each broadcast… 🙄 I had a hanging wire, but here again there is a problem with the length. I had it over other people's land… well, nothing much. Within my plot, a length of approx. 20m can be considered, with the fact that the ant would have to be powered at the end. Can you give me some advice? ?Hi
Well, as long as it should be mainly at 80m, the best solution, as for simplicity, unpretentiousness, of good performance and price is clearly a dipole or inv. vee (the same thing, just bent 🙂
It is better and more reasonable to agree with the neighbors and pull a piece of wire over their land (as long as they don't mind) – I have it too, how to build a structurally demanding vertical with a dimensional ground system of radials and adaptation (as long as you want, to make it work - I don't mean any substitute antennas). If you hold it at a sufficient height above the ground above the roof, you just run the coax into the hamshack and that's it. you pull your shoulders away - preferably at an angle to each other around 120 degrees-at least in my case, the impedance at the input approached this k 50 ohm and diagonal to ground. I have a power point (stred ant) approx. 12 m above the ground, one end approx 3 and the other around 7 meters.
Price of execution approx 30 eur (also with symmetrization) and walks like a slob 🙂i atenuator a kusok drotu, but in my opinion it is the most feasible, the simplest and cheapest solution, which also goes with all this 🙂
Sincerely, Peter OM4ASI
http://www.iw5edi.com/technical-articles/morgain-antenna-4080
http://www.qsl.net/pa3hbb/ll.htm
http://www.qsl.net/dl7jv/e.hf2v.htm
http://www.g7fek.co.uk/blogus/newsshow.php?page=80m_Antenna_for_small_gar_49493
http://www.nonstopsystems.com/radio/frank_radio_antenna_80m_vertical.htm
Akykolvek vertical, which will be less than 10 m will be quite narrowband on 80, I made a vertical for 10m laminate on a sota for 80 and 15, it worked, but only about 80kHz below PSV 1:2 at 80 and the reports were not too dazzling 🙂 It was also very hard to change the background, so I use a regular dipole for soty, often like an inverted V and that sleeps better within the scope of the possibility and with less influence of the ground and surrounding objects. Om4ASI is doing you good, if you can fit the full-size INV V, if you can't fit, so shortened, moreover, if you choose the location of extension coils or traps appropriately, so you get a multiband antenna, again, but for the price of a narrow band at 80 (pod 100kHz).
Morgain antenna is also a good solution for small plots, at the shoulders 2 x 10m has the largest BW of the shortened types of antennas (slightly smaller than a dipole) and also works on 40m.
I had an inv V dipole on the house from the beginning 2 x 12m extended with coils so, to go to 40 / 80I am at 80tke bol BW around 70kHz, also thanks to a nearby metal object. For comparison, the current deltaloop inspired by SP7LA has 80 pods 1:2 BW 240kHz and without tuner is also usable for 40 / 20 / 18 / 15 to cast 10m. Of course good “get up” 80-20m, but I won't hit the end if I broadcast on a higher band as well 🙂@brto wrote:
Hello,
I would need advice on building an ant, respectively what ant. I found a lot of antennas but I don't have much time to experiment with my work, so I would like to build something that works, ideal for the first shot.
Ant should be on 80m. It can also be multi-band, but mainly 80 will be used. Well, it would be best if it were something vertical. Ant will be in the cottage with the A-shaped roof. I was also thinking about the solution of building a vertical on the ground, but again it is a problem to make radials since I don't have such a plot of land. And in addition, make an ant before each broadcast… 🙄 I had a hanging wire, but here again there is a problem with the length. I had it over other people's land… well, nothing much. Within my plot, a length of approx. 20m can be considered, with the fact that the ant would have to be powered by
end. Can you give me some advice? ?
You will do the best, when you build two antennas, vertical and dipole. You'll figure it out yourself, according to reports from the stations, what kind of antenna is that?, to which connections it is vertical, or dipole antenna most suitable.
Read about building a DIPÓL antenna for multiple bands, the construction of which
solved by German radio amateurs. The antenna has a slight requirement for placement and dimensions:
http://otc.cq.sk/index.php?option=com_content&task=view&id=459&Itemid=45Hello, Brťa, I don't know why you are ashamed of your brand. It must be stated as well as your QTH. There is always an amateur around, who will advise you. To that antenna, you need to write whether you want it for DX or local communication. If for local communication, so vertical is useless for you. I would recommend the lying quad. You write about 20 meters. 4 * 20 is 80 m and you have it tuned. Or try this
Shortened antenna INV-VI was considering a new antenna for my favorite band 80 m, but due to the considerable length of the half-wave dipole, that won't fit on my roof, I was forced to think about it, how to shorten the antenna. I started to think like this: what if I wound a piece of the antenna on a roller, this would shorten the overall length! Well, hooray for that!
How it all turned out, you can see in the picture. I hung the center of the antenna on a mast from the former common TV antenna, he attached the ends to the edges of the roof – and voila! That works!
Well, as for the extension coil, so that's also very simple:
And the results? In connection with the transceiver according to the next picture, with power consumption of the final stage approx 3 W, reliably “I do” all of Europe. In time, it will be necessary to connect a balancing element between the coaxial lead and the center of the antenna, next week I'm going to the junkyard to look for some computer resources to gut suitable toroids.
And it is!
SELIA transceiver for the band 80 m, front panel dimensions are 3 x 7 cm, depth 7 cm plus others 7 cm box with batteries fitted from the back. The red and blue wire at the top is the terminal to the antenna and ground, possibly to the coaxial cable to the antenna described above. Key on the right, on the left, headphones from the Correspondent dictaphone from the 1960s.
Write to me at the address OM3CVV(zav) omradio.sk and I'll send it to you from fig
I have an old program on my computer, so it refuses to forward images to me. A shortened antenna is described here:
Mrs, thanks for the answers. At first glance, this seems the most feasible of the proposed options :
http://www.g7fek.co.uk/blogus/newsshow.php?page=80m_Antenna_for_small_gar_49493
http://www.iw5edi.com/technical-articles/morgain-antenna-4080
As for the second option, it just bothers me that it is fed in the middle and the coax would be sent to the middle of the garden. That is, for a better idea, the mentioned land is a rectangle approx. 20x15m where there is a cottage at one end and at the other end the neighbor's tree which he approved for me to use 😀 The advantage is that the cottage is relatively high so the ant will already be approx. 12m above the ground from the roof. Well, for example. inv I wouldn't have anywhere to fasten one arm because of the angle of the arms (not even with the neighbors).
Here I also solved the problem in the case of vertical, how to make ground radials. If I wanted to keep at least lambda/4, the radials would only go in one direction.
Even when it was mentioned whether I want local or DX. At the moment, I will be happy if it works at all, but from a longer-term point of view, I would prefer DX.
But the abbreviated inv.V… I have to run to the cottage and look there, with an arm length of 8 m, something could definitely be invented there.
I still have a probably not very smart question: purely theoretically, if I build, for example, a quarter-wave vertical on the roof of the cottage (so the heel would be on the roof, 12m above the ground) and I would bury the radials in the ground, connected at one end and connected to the radiator with one wire (with the fact that the total length would be lambda/4). Actually, it would look like one radial branching off after 12 meters. Something like this would work, or it would make some sense “branch out” ?
The dipole does not have to be inverted, you can make it slanted or straight, possibly bent. You can also make a shortened version of the windom antenna, but the problem is with the superstructure. Look online for companies that sell antennas, there are a lot of verticals, which do not have such terrible radials. Those radials do not have to be buried in the ground in any case. Look at the top dipole and try to stretch it 10 m 2 x four wires each and see where it resonates for you and tighten the rest with a coil. And I'll go back to the beginning, brand and QTH must be mentioned. I firmly believe, that's it 20 km will definitely be an amateur, who is past these things.
There are also verticals, which apparently have no radials.. I use a vertical antenna MFJ-1798 approx 7 m above the ground and somehow I don't miss the radials.
@OK1FTJ wrote:
There are also verticals, which apparently have no radials.. I use a vertical antenna MFJ-1798 approx 7 m above the ground and somehow I don't miss the radials.
OF COURSE he doesn't have radials, because it is a dipole built vertically, powered in the middle.
“… I still have a probably not very smart question: purely theoretically, if I build, for example, a quarter-wave vertical on the roof of the cottage (so the heel would be on the roof, 12m above the ground) and I would bury the radials in the ground, connected at one end and connected to the radiator with one wire …”
In this case, it would perhaps be possible to pull the radials from the heel vertically to the roof and then appropriately down and into the ground / on the ground …
Another option would be – build that vertical in the middle of the garden and bury a fan of radials from its base (so, so that they do not interfere with the use of the garden – the more, even better if they are buried, so their length doesn't matter so much anymore – they increase the conductivity of the earth …
Something about shortened verticals can be found e.g. in the Radioamatérský zpravodář from. 1972 – C. 5 (and about a year later also in AR in a series of articles by Jarda Erben OK1AYY).
After all, several articles about shortened antennas were published in the aforementioned edition of the Newsletter – especially for the lower bands ….Bomb's idea, if it manages to maintain the impedance and the radiation angle, it will be a great thing, but it probably won't be vertical anymore.
There are a lot of amateurs in both Púchov and Dubnice..Category QRP, to those radials and their length. So if I understood correctly, when they are in the ground (let's say 20 cm) so their length is not so critical ? If I have, for example, 20 m of vertical, then in free space the radials should ideally be 20 m (if I'm not mistaken), but if I put it on the ground and bury the radials, it wouldn't matter if they were e.g. 5 m long ?
Anyway, I'll look into the Newsletter.K tomo dipole a inv V – I will have to go to the cottage and accurately measure the distances of possible anchor points, this is a bad estimate.
My qth is Púchov, the brand should already be in the signature 🙂
year – it is so.
When the radials are in free space (raised above the ground), so it is good to have them resonant – quarter wave.
When you bury them, so they are in a more or less conductive environment and their number determines the transition resistance to the ground – the more there are (up to several dozen – at will), the lower is the transition resistance to ground and therefore lower ground losses.
Those 20 cm is sufficient from an electrical point of view (maybe in winter, when the ground freezes deep, the antenna's properties deteriorate), the question is whether it will be enough, when you run the wire through the flower bed …
For example, guide wire for fences is a good material (iron 3.5 mm galvanized) – it handles well and resists corrosion sufficiently. Corrosion must be resisted especially above the ground at the point of interconnection at the base of the antenna – connection to some plate of the same material – screw connections, or weld – he likes it – and treat with a suitable coating.….. I bring to your attention 8m vertical for all bands: http://g8jnj.webs.com/cometcha250b.htm
… on the balun, like toroids, I use snap-on ferrites for the cable….
