Wow ...when I saw the original video I thought exactly what you said. It is short circuited dipole. Then your video appeared in my tablet and you really explained the bad thing to that design. Only for a recomendation...I would use copper board and etched the center so there will not be a conection to the ground plane and reflectors. In order to achieve the long range of 3 km they will need and amplifier and a duplexer. If you or someone have a schematic or a design I would love to see it. There is a video where someone took a crystal from a old mobile to use it as a filter ....it will be interesting to see the modified gun with an amplifier and test the performance and gain....thanks for the video. I loved your scientific approach to the subject. Regards...
You unfortunately forgot the primary reason they were able to get a 5km range from the antenna; They're native Russian and their WiFi was powered by the power of Putin.
Great video. I have just made one today:) I have set the first 3 Only 10mm Apart & then 32mm to the 4th one at 38mm. I have just done a quick test on my phone & the results are very good. My phone on its own only picks up x2 Direct Wi-Fi Signals & x7 Normal Wi-Fi Signals. When I attach the Gun I'm getting X7 Direct Wi-Fi Signals and x18 Normal Wi-Fi Signals. I'm trying to connect to my local Mc Donald's:) Sometimes you just have to try these things out to see if they work:) Great video.
You should try it. It seems that the result depends on lots of factors. Personally I was surprised. I've assembled the antenna from some rubbish on my backyard. With the antenna I've got significant improvements in connection (though I have 3g antenna but not wifi one)
NO, the driven element is shorted to the boom at DC only, but not at RF. This is the same with all the elements, the centers of them are all at minimum current points, so the only difference between grounding them or floating them should depend on how far from resonance the measurements are, including any velocity factors. If they are at the perfect lengths and spacings, their zero current points do NOT see the booms at RF frequencies.
Not forgetting a 50ohm termination is probably more important. Testing the driven element to Director with s DC multimeter is not a valid argument. It's whether it presents a true 50ohm load. Look at a folded J pole antenna. It's a DC short with an infinite impedance at the antenna tip. However the 50ohm feed is near the bottom of the antenna and a DC short. In technical terms a transformer is a DC short however it's not to AC, ......RF is AC. Ok it's true your not going to get far with the driven element shorted in this way however I think the fundamentals of antenna design need exploring a tad more. Example your average Sky dish has an antenna about 15mm but its nestled inside the feed horn (can-tenna). Ultra directional however has a range of hundreds of miles potentially. Why not check the reactance, do a little J notation. 2m EME is a round trip of 750,000km and 23cm EME. Since 2.4ghz is in the 13cm band the potential for 10,000 miles is achievable IF both designs are capable. Having an excellent antenna at one side and the other possibly using a vertical to your circular polarisation antenna is 30db down perhaps as much as 60db. Build the design again and test the pair pointing at each other. Measure the thermal background noise and run this video again. Or Google 13cm EME www.vk3nx.com/13cm.html
Just a comment....the so called gun antenna is like the one used for comertial MDS television cable. The elements are circular because the used polarity either vertical or horizontally. In that way the waves are reflected in any position...that is another problem because if you have a transmission where they used separated transmitters your gun will peek both and interfere with each other. So that is the reason where a bow tye antena correctly oriented will work as well. But with respect to the impedance referred a 50 ohm....since we are talking about high frequencies here and probably people here doesn't realice that these things should be designed as transmission lines using what is called a Smith chart and a process called matching the impedance seen at that frequency....this is not an easy stuff to be explained here unless you have seen the problem as a transmisión line. With this I just want to say is not to put a 50 ohm terminator plug....the antenna should be matched to a certain frequency to get the most possible gain. But considering this is a WiFi transmission where they used many channels and in your wifi router you may specify which one to use , the you should take the consideration to cut the dipole dish diameter acording to resonate a that frequency . I think they use 1/4 lamda for that. Kind like the dipole on the LNA of the parabolic dishes used in the 80's. So forget about 50 ohms terminators and design the size of the dipole cutted to that channel frequency. Or forget what all of this discussion I just mention....😊
I'm not trying to be disrespectful, but why not test all antennas you made with Spectrum Analyzer to be sure that they run on 2.4 GHz ? It feels like an incomplete video.
prof20 int Agreed! More like use a sweeper or network analyzer. I don’t believe the dimensions are accurate. I have many 2.0-2.5ghz commercial disc rod/yagi antennas and the dimensions are much different. I don’t believe that antenna is properly tuned or optimized for 2.4ghz. A circular polarized helix antenna is much easier and woks much better. You can wind copper wire around a piece of pvc pipe and get a better antenna. Higher gain and a decent beam width. The half power points are more narrow on a properly designed helix design. A >15” long helix can get you 12dbi with 40 degree or less half power points. This disk rod yagi design will never make that spec. Unless it is swept and optimized. Still it will not result in a gain of 12dbi. 6dbi would be a stretch.
So you're saying helix antenna most likely better than that antenna in video for 2.4 GHz? I've made the antenna above and the distance is not great, less than 1.5 KM I have tested it.
Thank you for the video and your suggested mod that improved the design. Although, i have a couple issues with several assertions made. 1) DC short != AC short. AC will have an impedance with either inductive or capacitive reactance. For instance, it is possible to connect both shield and center wire of a coax to a copper pipe with their connection points separated by 90 degrees, and have an infinate impedence at specific frequencies. 2) The possible distance. You yourself pointed out you were shooting through brick. Then in the original video, one can see it was winter. Low humidity means low attenuation, and no leaves on the trees. And then the original video had two of these antenna roughly pointing at each other. And lastly he erected one antenna on top of his roof. All I am saying is that one might be able to get long range under very special circumstances, and it would be helpful to list them but advise that many things can detract from optimal performance.
Due to the construction, the cable appear to be of a certain resistance. This is due to the self capacitance and inductance. Take an infinitelly long wire, connect a power source, and it will seems like it is a 50 ohms resistor. Take a shorter one and you get the 50 ohms until the electricity reach the end, then it go open circuit. Any change of impedance cause part of the signal to bounce back. The transmitter expect a 50 ohms load and get a 75. Part of the signal then bounce back in the transmitter. You now have a few things that happend. First only part of the power goes in the wire. Then the reflected signal goes back in the transmitter, which now have to fight it. This cause the transmitter to heat more, and to deform the signal due to the overload. Then the signal hit the antenna, which appear to be a certain impedance at a certain frequency. Again, if the construction is wrong, the impedance will not match the cable, and part bounce back, and you get even less signal out, plus that signal bounce back to the wifi card, part bounce again there toward the antenna, part continue and hit the transmitter, which heat more and deform the signal more. All that signal deformation cause some signal issues... Look up for cable impedance, antenna impedance and signal impedance matching. RF is kinda like black magic. It do not do quite what you expect it to do. ... Also, did you knew that the electricity do not use the center of the conductor? But only 1.3µm at 2.4GHz. Google for skin effect (quickly, as the frequency raise, the electrons tend to flow only on the surface of the conductor, leaving the middle with little or no flow).
mismatch loss for 75/50 Ohm is not as big and given that 75 Ohm cables have generally lower attenuation it might be advantage to use them in low power systems. But yes, it depends on particular circumstances and it is good to know what you do.
Very interesting. Thank you. The only practical way to get things like this working correctly is to measure the VSWR. There are other ways but this is the easiest , simplest and cheapest so far as I know.
And they all build this antenna and "conclude" and "demonstrate" that it works for multiple kilometers. But it can not. Wifi protocol frame time is not waiting for more than 1.6 kilometers signal travel time. It will retransmit and then listen again, not wait enough and retransmit again. But happy to get a tip about the driver isolation. Do not want to burn some holes in wires or parts, so the smoke comes out.
I saw the video again that guy put directional antena on the roof of his house and u have in side of your home so may thats why he have strong signals, and the second mistake you told was right he can correct that .
The 5 KM figure was with line of sight and these antennas for both recieve and transmit! I know for a fact this is possible, because line of sight makes a huge difference. I say this from personal experience. With line of sight, i have managed to set up links of 10 km on just 10 mW.
Its perfectly possible to have a DC short on a good antenna(PIFA or slot antennas as an example). Its the impedence at the frequency of operation that matters. Clearly isolating on this improves the match, but it isnt a universal rule.
The problem is when connecting to an output that has any DC bias for driving an external amplifier. Any antenna that is a DC short will damage the output.
I was thinking they should be isolated, but i have also seen many antennas that when tested under DC current will appear as a dead short...cannot say which they used, but under your practical test, it was at least shown to work BETTER when the driving element was isolated. I like it when people independently test stuff that people post as being the next best thing since cold fusion.
The other vid was outdoors in a rural area that's how they got the 5km. In your vid you're indoors. So what your saying is it does work and it works best under 5km.
1) Short circuit when measuring DC, not on the RF! 2) there is no current flowing through the central line when RF recieved 3) incorrect measurement, this is hightly directed antenna for the free space, not for the office.
original video he put the antenna on his roof also its a directional antenna testing in garage is bios, should replicate the actual video to make it fair
I saw the video you are talking about and I knew there was something not right but couldn't think what until you put it right here. You may have saved my router's life! LOL
@@bansheemania1692 If it use approx 800MHz . (Harmonic frequency) The same effect of dielectric water resonance as 2.4GHz . I **believe** that it is the root of most cancers in the present day. However in the past, "The continuous of pulse" is too low (only "sound data" transfer for 2G ) In the present 3G-4G "the continue of pulse" for computer data is too high (ex. wifi 11Mb/sec) and this also has more affect to the "resonance" more than "intensity" of beams.(However "the intensity" for "resonance affect" must atleast beyond in some level see mathematical about Orders&Series then multiply by time)
@@bansheemania1692 It can cause no harm with Li-fi that use Lights or Infrared(GHz) instead of Microwave water resonance 800,2400MHz) PS.Except sending the red Light (Д=700M or F= 4.3x 10^17Hz) (c=FД ) in resonance frequency like 800Mbps or 2.4Gbps or harmonic still harmful
@@bansheemania1692 5G is a military weapon.. Plain and simple. It's the exact same technology used at the airport with those full body scanners. It's harmful. As is 4G 3G and the rest. You usually don't see the damage for 10-15 ish years. LED lighting is another creepy weapon that can pick up crystal clear audio ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-hliHBeC1sco.html Any claim that 5G (or any G of internet thus far) is not harmful or that it's not tested, is BS. The damage these things cause has been known for decades. The frequencies used with 5G are the same frequencies used to induce diabetes in rats. And all G spectrums are used as sterilization. Sure they're may be beneficial and safe uses for these technologies, however, idiots use them. And they've been handed to idiots to use, as weapons. Period.
The thing is every wifi signal is Locked today. I don't see anyway that this would work for that reason unless you already have paid internet and you want to boost the signal.
The antenna needs to be 50 ohm for communication. But Reference antenna conductive and it 0 ohm resistance. Internal impdance of IC 50 ohm and the antenna has to be 50 ohm for the maximum power transfer.
Andrew McNeil. Every wifi signal is Locked today. I don't see anyway that this would work to get free internet unless you already have paid internet and you want to boost the signal with your wifi antenna.
I made similar antena and connect it to router with original three antennas. I disconnected one original antenna and connected this wifi gun antenna. There was no difference in signal range. So not working.
The wifi antenna built here does indeed significantly boost the signal, however it isn't as far as the other video claims. But yes it does create a stronger connection.
im sorry but you need to understand that it is a directional antenna soo you don't need to base the number of wifi ssid scanned by the receiver what you need to do is to do a range test not scanning the number of ssid by itself,
Short answer: yes Long answer: the entire video Yes its legit, i use a bunch of aluminum tin-can, cord, wifi extender, bolts and nuts the range is extended up to 100sq meters or more
Not tried wifi gun yet, but i have built antenna and used GSM and 3g 4g frequencies and they are really good. They even catch up signals far away 30 to 40 kms away. As this design is yagi model. It may work.And i disagree from narrators some points.You say parasitic elements must be isolated, but yagi theory says that elements have a node (zero rf at centre) so it can be connected to metal boom.
But no the dipole .look for an vhf tv antenna and you will see why the dipole is isolated. Or if you love to strip LNA from parabolic dishes, you will find the small antenna in the wave guide is isolated from the chassis or metal body and has a hole to conect to the electronic board inside the LNA....
Well now you are speaking about putting shrink wrap on the boom. Well if you go back to the video in question you will notice him cutting down a wall anchor. Which I do believe you may have missed because he did in fact isolate the boom !!!
Thanks for the meters to feet conversion. I'm trying to switch to Metric... but I have 30 years experience with Standard. Standard makes sense if you're doing a great deal of fractions... however, I'll admit that(other than cooking), we don't do bother with fractions. Metric makes sense for almost everything and I wish it was taught first in school.
Very very clever video, from a real technician. The thing to connect all elements together shotcircuiting is a real stupid mistake from the russian guys, shows that they don't know the way a Yagi antenna works.
hi Andrew, thanks for this. I've always been interested in the "how and why" so I have a few questions: 1) do the plates need to be copper? is the conductivity of copper a benefit? 2) you say you've isolated the main plate but they are still attached by that wire? 3) maybe a bit off topic but I have two channel master tv antenna mounted on a mast, one above another. They are on a 30 degree angle from each other (I've experimented with them parallel and up to 90 degrees to each other. 30 degrees seems to work best) Each one is about 2x2ft so I have about 8 SF aiming in the direction of the sources, whereas a yagi design has very little frontal area but perhaps has more of a chance to lock the signal since its longer and deeper. Which is a better set up? thanks.
Make the driven element a copper ring riveted on a non-conductive disc to isolate the center wire from ground. However building this design is a waste of time.
I also built one and couldn’t get it working I think there needs to be rubber in between each copper ring and the boat they’re attached to is steel that has way to much resistance. Solder a small wire to each individual plate through a hole drilled close to the bolt and you can use a plastic bolt but either way, I feel the steel bolt is slowing the flow of signal to be cut from Wi-Fi. Small wires for small voltage right? My theory is too much resistance in the steel stop the flow of signal from Wi-Fi
Impedance is quite important. don't try antennas with bad impedance or obvious isolation. as the op mentioned if you use an amplifier it can burn. baby burn and eventually damage the receiver electronics
Thank you for taking the time to make this video! Regarding the original video I was also wondering if there's any merit to the way the phone's antenna got connected to the "wi-fi gun'', I mean that repeating bending of the signal wire at 90 degrees to form something like a spiral?
Thanks for the detailed video. I would live to build an antenna and have done a fair amount of research and always got confused when it came to the elements. Out of curiosity, the video you're referencing bent the end of the wire into a square spiral and held it near his phone to increase the wifi range of his phone. Is that possible?
You clearly and obviously missed the part where he used a TV Aux cable designed for TV analogue radio waves to significantly boost the signal over a longer distance.
I am trying to receive my Wifi signal from my main house to our second house on the farm. No trees and no interference to my cell phone . How do I do this ???
Nylon threaded rod is not very strong. There are many better options available. www.mcmaster.com/#threaded-rods/=1cn8i6c Hopefully it is not too late for the comment to help.
Others may want to go down the path. We can offer a bit of help. Things made with 2 metals touching don't work very well outdoors. In general, dark colored plastics survive the sun better than light colored. Polycarbonate is strong but goes bad in sunlight. Acrylic does quite well in sunlight but is not strong.
When we go South to avoid the frigid winters of the South Dakota high plains, we stay at a nice little rv park in a tiny Arizona town near Needles California. They furnish wifi but it is slow and not at all reliable. I finally decided to buy a sort of booster, and that helps a quite a bit, but since it is inside our RV, which is made up of steel 2x4's with fiberglass body, a lot of signal is lost. I have been looking at hooking up a small outdoor antenna and runing it into our RV then hooking it up to a twin antenna router to be rebroadcast in the unit. Would this antenna design be OK? I did find a yaggi antenna and purchased it a few years back, but have not hooked it up as of yet because I did not have proper cabling capability. It came with some sort of coax but I am not sure exactly what it is, not 50 ohm or cable tv, someplace in the middle. The seller said they had it mounted on a sky scraper window ledge and used it to transfer files from one building to another some distance away, but had upgraded.
Too funny, I just watched their vid late last night... and I immediately thought of you. It would be interesting to test on your equipment against your compact yagis.
can u make a detailed video on how to make it just like that, pls my wifi is very bad from 75m away, if u could please list the things u used and the lengths and widths of the items thank u
Tried this years ago with tinfoil Cone youll get about 100 of them out of a role of alcan aluminium . £<a href="#" class="seekto" data-time="60">1:00</a> out the £ shop Increased my distance and strength .was well chuffed Note you can use the spare alcan for a tinfoil hat . :)
Could someone please make a list of all the materials/best materials to make one of these and their measurements? I'm thinking of creating one for a little project to keep me occupied, it would help a lot, please and thank you. EDIT: It would also be helpful to know how to attach it to a router, please.
I have the exact same Wi-Fi gun except plastic shimmy on the driven element and made of aluminium so it's kind of potato it's not really good the pics up the nearest wifi only I checked with the multimeter the driven element is not in contact with the rest
Why not try to adjust to the circumference equal to the perpendicular angle of perspective as to maximize the range and diameter of the latitude......lol hmmm?
Instead of copper disks, why not use single-sided PCB stock? Then Isolation is a simple task--just scribe a ring into the copper foil of the isolated element.
The antenna does not look in closeups like it was built to spec. The front disc is farther away than it is wide! Disc diameter should be 37 mm, distance 29 mm between discs, 1mm thick copper. Pause at ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Nk-nj_BwoBE.html