Parabolic Double Biquad 2 4ghz
Вставка
- Опубліковано 18 вер 2024
- So I made this on the fly after finding an old project from 15 years ago. This video is a little longer than usual as I wanted to show all the steps of making a double biquad.
A double biquad has a gain around 13 to 14dbi if constructed properly. Now if you replace the flat reflector with a parabolic curve you can increase this to 15 to 16dbi.
Support me on Patreon: www.patreon.co...
My eBay store: www.ebay.co.uk...
Facebook group: / 1313077415524264
Email: andrewantennas@gmail.com
Template: drive.google.c...
My shop: andrew-mcneil.com/
Donations: www.paypal.com...
Thanks Andrew, brilliant.
Just to say that I have just replaced a large, cheap Chinese Yagi with a parabolic, double biquad, based on your design. It is actually being used outdoors, so is built from 2mm thick aluminium sheet and (2mm diameter) galvanised fencing wire. The sheet aluminium is too difficult to roll into a parabola, so I calculated the angles to make two bends each side into a rough parabola that approximates the one shown in your template (its actually a remarkably close fit). A bulhead N connector is used to connect the driven element. Perspex (acrylic) 15mm spacers are used to support the double biquad element, with slots to take plastic ties, which are used to fix the element. There's also an aluminium bracket pop riveted to the back, with holes to enable the antenna to be attached to a pole and the elevation adjusted. What I find amazing is that it doesn't look like it should do the job relative to the long Yagi but provides a stronger, more consistent connection to an omni antenna that is just under 1 kilometre away. Best wishes, Ron - Wellington, New Zealand.
As always a great informative video, I have learned more from our videos than I did after four years of university. Thank You Andrew.
wow andrew. great antenna knowledge. you are so freaking smart i wish i could have one of these. these are so awesome. it's amazing the way you know how things work. you put a lot of effort into what you do here. It pays off too.
+Russ Krieg Thanks Russ i appreciate the feedback
Very Nice Presentation! Like the way you suspended the antenna lots better! The curve is just what that antenna needed. Also I believe the sleeve is acting some like a balun to fix SWR problems in the antenna. Nice is all I can say.
Thank you again for a cool video.
Jimmy, ARRL TS, WX9DX
amazing and consistent explanation Andrew!
I try
@@andrewmcneil wow, did not expect to get a reply. your calm and consise way made me really enjoy the video even though I am not buiding antenna at the moment. I wish teachers I had had same class.
Although supporting the biquad at its extremities may be best for sturdiness, they are the very points where the voltage is at a maximum and therefore the Q and tuning is most easily upset. The resulting performance drop would be most apparent if used outdoors where the insulating supports are exposed to rain and atmospheric pollution. Moving the supports to the points where the wires cross (voltage minimum, current maximum - so lowest impedance) may be less mechanically solid, but would make them much more 'invisible' to the RF.
Amazing job Mr. Andrew, I might build this one it looks ways better than the current Biquad I'm using now.
Hi Andrew,
Your videos are very informative and helpful. Iv'e noticed on some videos you post parts list, templates etc. ie. A build guide... This would be a very nice feature to include on your builds. This one in particular got my attention and I would really appreciate more details of the perspex spar dimension etc.... I think I understand the depth of 15mm and the height is appx 90/95mm but the width is fuzzy. Thank you again your you numerous, very awesome contributions to the community. :)
The width is not that important .Just a dimension that will support the wire and attach well to the back plane.
Fantastic job as usual, gonna try to do this double biquad ... lets see the result.
Thank you Andrew!
Bruno Linan I don't think you will be disappointed Bruno.
Ever thought of using copper coated MIG welding wire? Welders usually have discarded wire or better still whole coils of wire (with copper pitted) that they throw away. 0.6mm 0.8mm, 1mm, 1.2mm thicknesses are common. The copper makes it good for tin-lead soft (electronics) soldering.
Great videos,I will be making one in the next few days.
Do you have a running list of how each of your designs stack up performance wise?
+Bill Roberts I was thinking the same exact thing.
+Bill Roberts ill third that!
+Bill Roberts fourth that! i think its a matter of practicality vs design at some point, and the biquad yagi is a balance of both. i'd imagine getting it to field test all of his designs is going to take months unless this is his fulltime job, youtube i mean.
+Bill Roberts fifth that.
+andrew mcneil posts GREAT antenna explorations and this one looks particularly useful for my situation. If you are using WiFi, you probably ought to know how this stuff works.
You can simultaneously extend your coverage and reduce your exposure, if either of those considerations matters to you. And you can do that at extremely low cost. I subscribed to his channel a while back and this video just showed up in my youtube feed.
joe breskin Thanks Joe
Is the element soldered to both the back reflector AND the inner coax, or just soldered to the inner coax?
@confetticamouflage4141 Dear, to get your answer please watch his this below video by clicking on this below link where he has made this same antenna but with a plane sheet as a reflector instead of using this parabola type mess. Here is the link of that video--
ua-cam.com/video/WgLsPkqGCnQ/v-deo.htmlsi=lWzW4ttOoZZ_4NOM
As others have mentioned it would be good to know how the designs perform against each other and perhaps others in the real world so we all can decide on which design make the most sense for us.....Or if buying one is a better idea.
Yet another cracking video Andrew !!
I have now built this antenna and 3D printed the supports as I said previously. The results are excellent with the number of APs detected being more than double that with a rubber duck. One question, are both centre points connected to the driven element of the co-ax or is one soldered to the braid. It's unclear in the video, and looking at other bi-quads online, they all seem to have the centre points of the bi-quad connected to the driven element and the braid respectively. Currently, I only have the one centre point connected to the driven element and still I'm getting good results.
Mny thanks for you time in making these informative videos
Chris
Hello Andrew. This was a great video and a great build for me. I have been trying to squeeze as much distance out of these difference types of antenna for the 2.4ghz band. What is your take on a triple biquad antenna?
Does the focal point reside at this magical 15 mm as well ? Or do you not use the focal point in the parabola at all ??
Also wondering; if the 15cm spacing is NOT at the focal point for this F/D (and it appears not), there is significant loss of gain.
Otherwise, excellent video.
Nice work
Nice!
I was watching this video and thinking about the accuracy of the different lengths, it occurred to me that using copper tape or a PCB may be a way of ensuring the necessary accuracy. The next clip I watched was the biquad yagi antenna construction! It's always nice to find out that someone else had the same idea and I wasn't going off half-cocked!
One thing puzzles me, why is it vendors sell the clover leaf 5.8GHz FPV antennae as a set, one Tx, the other Rx? What's left and right handed antennae all about and what has axial ratio to do with it?
I think a tutorial on 2.4 GHz and 5.8 GHz (and 1.3 GHz?) antenna systems, covering the various types, their advantages and disadvantages, "easy" modifications Rx/Tx differences etc would be incredibly useful for the "not electrical engineers" out there. If you aim it at the Radio Control/FPV/Multirotor/long distance FPV etc. group I think you will get a lot of interested viewers (buyers?). Just make sure you reference the different areas in the title! May even help fund that laser cutter/CNC machine mentioned below.
I intend becoming one of those FPV quadcopter flyers, hence the interest.
Keep up the good work!
I love this video, I would also like to replicate this antenna. Could you please tell us what gauge wire was used in this video?
It is not clear to me what is a proper distance from reflector to get maximum gain ...
let say i want to build reflector from nescafe thin can and i will cut it to half then connect double biquad?
any data please !
I was thinking you could laser cut your perspex parts with a slot which would hold the parabolic shape without any fasteners. Laser cutting those parts would be really cheap too. The curve would be very accurate. Nice videos too btw.
Robonza Hi Robonza buying a laser cutter is top of my list hopefully soon.
+andrew mcneil , if you buy a Lasercutter, please tell us your expierience and the Model of your choice and why?
Hi Andrew great channel iv been hooked all weekend I have a question about the antenna as in how wide would the reception angle be as I'm building a gps guided fishing bait boat which uses wifi telemetry sent to my mobile phone but iv been struggling to get any range over 70 meters so I was planning to use a repeater and was wondering if this antenna would be a good candidate or do you have a better suggestion as I would like a ranger of over 160 meters if possible
All the best
Mark
The biquad is a good choice for a first build as it is a very forgiving antenna because if you are out on some of the measurements it will not hurt the performance as much as some other designs. If it is narrow beamwidth and longer range you are looking for then maybe a 14 plus element Yagi or a cantenna maybe more helpful.
can you provide in text.. the exact measurements of all angle.. please.. i can't understand in audio.. thanks
It's a square so it's 90 degrees.
Andrew
I've built a few of your antennas and am now looking to build the parabolic bi-quad. Im going to 3D print the 4 curved element supports rather than fashion them out of perspex. Unless I missed it, I dont think you gave a dimension for the depth (distance from the refelector to the element) of the support. If you could advise then I can get the .stl drawn and the print done. When I have them I will publish the design to thingyverse and send you a link so you can'if you wish put the link on the you tube video for that antenna.
+Chris Short Thats also my question. What the distance of the spacer from reflector and the Elements?
+Hans B. It should be 15mm, same as the other 2.4Ghz Biquads.
Greg Liebig mesh size 200mm on 100mm i have watch his video again :)
I've build one blade antenna out of your designs and measurements and I'm pretty please with the results now that I'm getting 26 mbps up and download from 25 meters away from a router with NO antennas between one 50 cm stone wall and one 30 cm brick wall, but my question is can you just add more elements to the blade antenna to make more powerful? or is there any way to make it better?, I know that I can go around the problem and fix it, but I'm really interested in a blade antenna as the results are impressive...
Luis Salguero Hi Luis I always love to see comments from people who have had a go at building some of these antennas. Every antenna has a plateau of performance I have some spare time coming up soon and people have asked for the blade in the shop so I will do some tests and let you know.
andrew mcneil thanks man, thank you for the time you put in all these videos and for sharing your knowledge, I was hitting my head against the wall before I saw one of your videos, and now I've understand a lot, so that's why I've came up with that question, " is it possible mathematically just add more elements without coming to a full length element and loose radiation, hence performance...
Would there be much benefit to having some director elements like a Yagi?
Interesting and inspiring video. Why is the double biquad not in the reflector's focus point. Is there any geometry behind this or are you just testing randomly? I'm new to this so this is not a critique, just a question. :)
80% of the elements are at the focal point this is a 2 dimensional parabola it has a horizontal focal point across its length. Unlike a 3 dimensional parabola like a dish that has a single point.
@@andrewmcneil Thank you, then it was my eye measurements that fooled me. I plan to build an approx 3 times larger for 4g lte @ 796 MHz.
@@SuperKoaren just a little bit bigger than 3 times but good luck. If you can pick up 4G at a higher frequency around 1900 MHz it would be a lot faster for you.
My favorite ;)
Really enjoying the videos Andrew.
Does the parabolic curve make the antenna less directional than a simple reflector?
+Richard Thornton Thanks Richard no it makes it slightly more directional it had a narrower beam width that gets narrower the further away it is.
+andrew mcneil thanks for the reply. Thought the parabola might collect & focus from a wider area.
It is unrealistic to expect a plot for all the antennas you make but it would be nice if you could include examples of what shape might be produced to help us viewers to choose suitable antennas for our applications.
Keep up the great work😀
can you please tell me the curvature of the Perspex what is the radius of the inside and outside thanks
There is a template in the description
What is the size of the mesh? I looked at your template and read the comments but cannot find the specs or the overall size of the reflector.
It doesn't have to be a mesh. It could be any sheet metal.
Sir, I am a big fan of yours. I have watched your most videos. Now I want to know, what kind of antenna I can use for my router to provide hi-speed and long range network. And how to gain transmit power of 2.4GHz network. I have made your biquad antenna. It is receiving other network, but don't broadcast my network. What can I do? Please help. Thanks.
Great work. How about a parabolic curve for 5.8 GHz.
Hello Andrew I'm from India using 4G Wireless cellular router/modem over ( BSNL 3G ) HSPA+ and geting 18 / 31, dBm : -78 . the cell tower to my rooftop handmade antenna is 3452 foot towards north-east 27* the speed is quite low. when the distance is good and the router I won is good for now. can I upgrade the cell antenna? I watch many of your videos its basically over wifi technology. I don't have that much knowledge over antennas so I wander could you please guide me to make a cell signal antenna for my rooftop to catch better signals here. your help in this regards will be highly appreciated.
I am thinking about doing one of these but with a carbon fibre deflector dish. Does the cf act well as a reflector being as it is conductive?
You are confusing conductivity with reflectivity....carbon is fantastic at absorbing microwaves. Think stealth fighters, they use carbons (absolutely no external metal). Use any metal
Can you put parasitic elements to get a little extra range?
Other than the parabola being more focused (narrow) on the old antenna, I notice it is on the other axis. Is it relevant which way the parabola is curved?
+Ronin Iscandar It absolutely does. The focal point of a parabolic trough follows the trough the way it is mounted on the new antenna. This is really a great design as well as both cheap and straight forward to assemble.
+wrathofsocrus I assumed so, but there is no detail. Is it as simple as narrowing the radiation pattern for more gain along that axis?
+Ronin Iscandar It works two fold by bouncing waves coming from the direction it is pointing and by reflecting them back out in the same direction. Wifi radios are transceivers so they both send and receive data. With a dish it creates a single point of focus and a trough creates a line parallel to the trough. You can check out his 2.4GHz Parabolic Blade Antenna video or look up solar parabolas. Light and RF are both waves and they reflect in a similar manner.
+wrathofsocrus I understand all the basics. The question was effect of trough axis change w this antenna. Critical bit of info is that despite looking like it might have a strange pattern, it is fairly round or egg shaped (slightly narrower horizontally). So unless bending of elements themselves like he does on the first one has other effects, the answer is yes, its just which way you want your pattern to focus.
please help me understand. why do you heatshrink against shorting, when you just solder in the middle part of the antenna? Doesn't that create a short?
Paul Murphy thank you. I kinda get it. I just need to read and play around with it more.
Sir, can I make a (14 element or other) yagi antenna on a pcb?
sir do you have a video where you connect this on a router
any signal loss via the tripod bracket?
what is spacer diameter please add teplate paper. (Sorry for my English)
Show how you hook it to a iPhone and computer please
Where do you get your small tripod from?
Tried to visit your website but it says "Forbidden
You don't have permission to access / on this server."
Do this antenna work the same way (performance) for 3G and LTE
Yes, if you listen closely to the video at some point he says something like "Any antenna works with any frequency, just dont think too hard about these things.."
is that antina can use any router
Hello from former SSSR)))price of such an antenna
Priceless!!
1) Andrew any suggestion where i can get that mesh? is construction material? what department it belong to?
2) is the mesh like this www.ebay.com/itm/Stainless-Steel-Woven-Wire-Mesh-30-mesh-6-x-6-Type-304-filter-grading-sheet-/251508306847?hash=item3a8f10339f - would it work good? thank you!
It doesn't have to be a mesh. It could be any sheet metal.
Get mesh size?
The wide?
Can this be used as a transmitter as well as a receiver?
No no this antenna is strictly for reception purposes ONLY as it is unable to receive any signal. GLAD I COULD HELP.
:^)
Is it ok to 10x the size?
sorry I don't understand your question
Why mess ?? Why not metal sheet?? Does anyone have the answer??
As long as the mesh holes don’t exceed the wavelength it saves weight and if using outside reduces wind damage.
@@andrewmcneil Got it professor I really salute your hard work and efforts for your passion . I have another rookie question and need your help please, how could I know from the mess holes that if the mess holes are actually exceeding the wavelength?? Let's say I have a mess square ⬛ hole of 5mmx4 sides, so how could I know if this hole size is exceeding the wavelength of not?? for a 2.4 GHz signal the wavelength is 12.5 cm, so how could I varify that??
💡💡And here there isn't mad wind 🌬️ offcourse, so if I stick to use a solid metal sheet instead of the mess will that be a good idea??
Love you from India ❤️
Видимо это первый коммент на русском. Лайк
What do you do with it...?
If a dubble biquad has gain over a signal, have you tryed a quad?
Wire is 2mm or 1mm
1.4mm
По вашему способу антенна самая мощная, без тарелки именно эта? конечно направленная.
+Alexandr Tsoy именно!! я вчера сделал biquad on CD и вообще очень был удевлен результатом!! biquad очень не плохое усиление! сейчас пробую эту сделать! попробую вместо сетки желеяной просто жесть с банки с под пива! посмотрим что оно будет!
Is there a better way than trying to copy the parabola manually like this: imgur.com/PIRxEtX.png ?
the perimeter of the antenna corresponds to 1.2 Ghz and changed shape not good at all even for 1.2Ghz. forget about 2.4G
i will give you a very near mint condition iphone s 6 + for one of your good biquad yagis....i had a thousand dollars and was all excited when i saw this kickstarter page i dont know how it works but apparently i was to late.....life is so unfair i need drugs to cope with the loss of the opportunity :P
How many db is the gain
11
@@andrewmcneil TNX
Best 73
I would like to do for
Ham 1.2G Band.
Biger twice lambda...
@@miranslokan2478 you can give it a go but i am not a ham so have never built on for that.
You did'nt have to do multiple build because of your experience. Doing a Biquad for you is like boiling water.
Well it is my favourite antenna LOL
reflector is too big for 2.4Ghz and focal point useless because biquad element is too wide and more like for 1.2Ghz as reflector.
I was thinking the same. The parabola is so flat that the focal point must lie far before the double biquad element. Probably with the current dimensioning, the mesh just functions as a reflector, more so because the element is positioned 15mm in front of it (instead of where the focal point is). I think the 'old' antenna based on the Windsurfer has a bit poorer performance because it is way more bent, and the biquad element is bent with it. It would be interesting to see a comparison of this new parabolic double biquad with a double biquad with a flat reflector behind it. My guess is they will perform the same.
I built bunch of double biquads and they suck. single 1/2 wavelength square reflector with lips much better. www.ebay.com/itm/WiFi-Antenna-16db-Biquad-cantenna-Wireless-Booster-Long-Range-GET-FREE-INTERNET/162829697269?hash=item25e96800f5:g:AwwAAOSww3tY7i5a
STOP STARTING SENTENCES WITH THE WORD"SO"!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Nói nhảm nhiều quá.