Building a 2.4 GHz WiFi helical antenna

Рет қаралды 102,672

Күн бұрын

Taking way too long to talk about helical antennas and then somehow trying to build one on camera.
This was supposed to be a part of the satellite reception series of videos, but I ended up not considering it one due to the topic being so broad and applicable in everyday scenarios, such as the WiFi antenna build you will see in this video.
Links:
My website and other social media - sgcderek.github.io/
Helical antenna calculator - sgcderek.github.io/tools/heli...
3D printed scaffold - github.com/sgcderek/dsgc-heli...
Timestamps:
00:00 - Introduction
01:48 - Antenna polarization
04:24 - Helix examples
07:03 - Needed materials
10:14 - Making the reflector
15:58 - Winding the helix
19:57 - Attaching the connector
20:54 - Matching strip
22:59 - Finished antenna
25:00 - Performance testing
27:41 - Conclusion
Music:
Cosmic Love - Bruno E.
Hanging Out - Bruno E.
Sunny Morning - Bruno E.
(can you tell that I didn't bother browsing the audio library that much?)

Пікірлер: 220

@sethalump Жыл бұрын

I'm floored by the effort + attention to detail you've put into this. You tackle the most difficult types of DIY antennas with ease. You explain it well and don't get lost in the annoying math.

@laurioxas1 Жыл бұрын

This is something Im going to try this weekend. Have a garage about 70meters away from house. Edit: Holy smokes, antenna works as a charm, tested with my phone, and about 50 meters away its still full signal. speedtest also shows same result as if I was standing near the router.

@alexs1382 Жыл бұрын

Great video. The humor peppered in cracked me up. You've had the best videos on antennas I've seen so far. I'd love a video showing a DIY double helix for wifi.

@blaketurner9389 Жыл бұрын

Sometimes wrong is better - together we all learn. Perfection doesn’t teach anything, it just looks prettier. Thank you for being honest and real. - So we all learn. Too few channels delve into the realities, they just goo for pretty. Thank you. Subscribed 😊

@coreyb4073 Жыл бұрын

We built high gain antennas 20+ years ago trying to network our houses together, pringles cans, satelite dishes, flower pots. our ultimate problem was the ficus trees in our area acted as giant radio sponges. we were able to get up to 3/4 mile range in a straight shot.

@dereksgc Жыл бұрын

Yeah shooting microwaves through trees is a losing battle. I'm hoping I can get my hands on some of the 900 MHz routers, that would be quite interesting to see how they compare to 2.4 or 5 GHz, it should be able to reach further and better penetrate obstacles, at lower data speeds

@GilmerJohn Жыл бұрын

We, too, have the vegetation problem. But a part of me in interesting is seeing what it would take get "borrow" the WIFI from a McD's about a mile away.

@8bit711 Жыл бұрын

Pringle cans.. the memories!

@Lampoonlongtails 4 ай бұрын

I like the use of the old fridge. And the 3D print form for holding the helix. Another excellent project, almost complete (don't forget the weatherproofing). 👍

@JohnOverstreet Жыл бұрын

Thank you for not cutting out your mistakes when editing the video. This is what it's REALLY like making something of your own! It's good that you know which parameters matter and which don't. I was glad that you expanded the hole for the center conductor of the type-N connector. I was telling the screen that the hole should be the same diameter as the dielectric in the connector. It would be interesting to see what the VSWR curve looked like. Do you have a nanoVNA?

@dereksgc Жыл бұрын

Yeah I do have a NanoVNA V2 which can measure these, but I didn't really want to add that information into the video to not make it even longer (and the point was to show that you dont need any special tools like that) I do however plan on making a loose continuation of this topic where I will most likely do the full measurements as well as long range testing

@JohnOverstreet Жыл бұрын

@@dereksgc Cool. I would really like to see what bandwidth you ended up with.

@RinoaL Жыл бұрын

I'm going to try to find a reason to use this in a video. I really love how you presented this. Very useful!

@Joe-ir4cd 11 ай бұрын

Love your videos !! Way back, when I started the FCARC ham radio club. A fellow ham and I, set-up a temporary repeater on 444.250mhz. We didn't have an outdoor cabinet to mount the gear in. But we did have an old refrigerator ! So we used it to house the radio, controller, power supply and duplexer. We dubbed it the "Fridge -a- peter" !! It worked out very well and got some laughs too ! Keep up the great work !

@excitedatom1403 2 ай бұрын

You're the first person I've subscribed to and pressed the bell icon for. Thanks so much for your videos! Keep it up!

@MrRObot-bin Жыл бұрын

Keep doing videos please, this a gold mine.

@chopper3lw 11 ай бұрын

Dude! I completely love your video style. I don't know anything about HF and antenna voodoo, but I just could not stop watching your video. Hope you get the money to resurrect your refrigerator soon. Thanks for teaching me a little. I wish I understood more about left vs right circular polarization, that hurts my brain a little.

@n1vca 11 ай бұрын

Fantastic work, thanks for sharing and explaining all the antenna basics ahead of the built 👍 Greetings to the Czech Rep from Munich, Germany

@gordslater 11 ай бұрын

I am impressed you used a spider as a drilling template for a hole

@dilushasamarasekara9533 Жыл бұрын

Nice practical video as always, looking forward to more content like this...

@justanotherguy3850 11 ай бұрын

Thank you very much for an awesome video with great attention to detail and recording of the results. Your proof of concept is valid. Here in the United States we have many bicycle races, running marathons, and other things where we have rather elaborate communication centers that are set up with data that must travel some distances. Using 100 ft Towers with 1 and 5/8 in heliacs to feed the antennas really gives it the range. I would really be interested in seeing how the helical would perform. I look forward to more from you in the future when you are able to establish stable tripods that can get you above the curve of the Earth.

@ethonwilles7043 Жыл бұрын

Great video. Very informative, would love a video on your ground station, and how/if you automate the collection of sat images.

@Dan-qp1el 7 ай бұрын

You do a really nice job on your videos! Really enjoyed it.

@romanescu_misha 11 ай бұрын

The 995MHz antenna showed at the begining looks rather like a marine (or currently a submarine) communication equipment not the satellite 😀 You've made my day, really.

@fotografm Жыл бұрын

Excellent video and I love the green fridge idea 🙂

@coyote20030 11 ай бұрын

Hey, thanks for your time and effort making this video!

@edgeeffect 11 ай бұрын

I was watching one of your other videos and thinking "why has he got a fridge outside?" and thinking you must be crazy or something... now it makes perfect sense!

@teslastellar 11 ай бұрын

Great video and explanation 👍 Thank you and keep up the good work 😊

@simonhaddow5052 11 ай бұрын

Great job! Axial mode helicals are my favorite. Subbed

@dereksgc 11 ай бұрын

Then get ready to see it again very soon

@DaFirebird 10 ай бұрын

Wow, the print quality on those 3D prints are amazing! What printer are you using?

@peakinout1 Ай бұрын

Yeh , great vid well done , easy to follow & simple test . keep up the great work.

@bromisovalum8417 4 ай бұрын

Nice work, great instructional video! Some weatherproofing maybe but performance is quite nice.

@MrCarlsonsLab Жыл бұрын

That looks like a lot of copper for 2.4 GHz. In a tank circuit, that would most likely be under 30 MHz somewhere. Have you connected this to a spectrum analyzer to see where it's peak is? Maybe I missed something?

@dereksgc Жыл бұрын

not this exact one, but similar antennas I've made did have a resonant peak around 2.4 GHz, sometimes slightly higher or lower but they are wideband enough for that not to be too much of an issue

@pseudo_goose 10 ай бұрын

Helices actually have two radiation patterns, depending on the dimensions you choose. If the circumference is much smaller than a wavelength and the pitch is much smaller than 1/4 wavelength, then they do act like a dipole, with an omnidirectional "radial" pattern, perpendicular to the axis of the helix. But in this case, it's a directional ("axial") helix antenna, where instead the _circumference_ of the helix is proportional to the wavelength, and the number of turns affects the directional gain. Then, the maximum gain is in the same direction of the axis of the helix. The Wikipedia for "helical antenna" goes into more detail about those two modes.

@AlexCausey 11 ай бұрын

I have been thinking about building 4 Helical antennas for, 1296MHz EME. 2 left hand and 2 right-hand polarization with one feed point for a 4.5 meter dish stacked very close together. Those printed coil supports look awesome.

@balanbogdan9160 11 ай бұрын

the fridge server is genius actually!!

@tanasegabriel1899 11 ай бұрын

Biquad behaves better when there is no direct visibility to the helix. At the helix antenna, in addition to the drop in reception level from linear to circular by -3dB, the reflected signal has reversed polarization and is not received by the helix antenna. It is ideal to use helix antennas in both parts, installed in a place with direct, unobstructed visibility. You can also use a biquad or helix as the primary antenna for a parabolic antenna, which seems to be sitting next to the rack, unused.

@roadkisserful Жыл бұрын

Very nice video I just saw a reason for buying the arcdroid cnc cutter. Also you could a fibreglass radome to cover up the antenna so the frequency cannot be disclosed to the authorities. :-)

@sauravmodak507 Жыл бұрын

Thanks for keep making videos

@TheMrDrMs 10 ай бұрын

neat. I built and use these starting in 2013 for my drone photo/video business(at the time). Before then, Soda cans for home wifi (like idk 2007?) Now, am an active amateur radio enthusiast and building all sorts of fun antennas. I don't think I heard it, but your method to attach the center conductor is perfect, but really ought to be measured and kept at a distance that maintains a 50ohm insulation gap, which the hole in the reflector perfectly accommodates. Where it seems it might be too close is that 3d print might be dipping down before spiraling up. But that's just nit picking, and your results clearly are good. Great video!

@TheBeardedDog 10 ай бұрын

Thanks for this video. I definitely want to try this with my Internet connection which is cellular based. One recommendation on testing. You should give iperf a try. You could setup the server on a workstation in your house and then run the client side on the laptop in the fridge. That would tell you the true bandwidth between your house and the fridge for the two different antennas. Who knows, maybe the helical antenna is ever better than 4 times.

@Abhishekseervi0 3 ай бұрын

My phone has weak signals I am thinking of making this antenna for a mobile phone, will see if it works 😂

@mauricesteer8023 11 ай бұрын

Thanks for you video,super keen to print and build one of these to be able to tap into my household wifi from my workshop which is about 40 m away. I'm not much of a tech head and was wondering what i require after the antenna to have wifi to multiple devices in the workshop.

@peterxyz3541 11 ай бұрын

Fascinating!!! Thanks. I’m following

@Baraka-yl2dp Жыл бұрын

Great video. Thanks for sharing.

@ColGs3b 11 ай бұрын

Drill hole pattern reminds me of the Orion constellation. Could make a stencil for getting the hole positions.

@andreyl2705 11 ай бұрын

Thank you) Very useful tutorial

@rickt1866 5 ай бұрын

you should add some weather stauion stuff just for fun and you you have the space. the fridge is sweet. thank for uploading.

@yxhankun Жыл бұрын

great work.

@WiegerBonwonderfulwb Жыл бұрын

Fuck! Now I want an Antenna Fridge too!... But first I need a garden :-/. Also I love this DIY video with the simple but very complete explanations and considerations. Btw, what kind of antenna is on the other side? a normal wifi router or an other helical antenna in the same turning direction?

@picobyte 11 ай бұрын

Has one here. It just works.

@user-ot8tb8jk3t 11 ай бұрын

Very pleased to see directional instructions for a russian military ship.😂 That's a great bonus to awesome content! ❤

@txfalkon2882 11 ай бұрын

what is the diameter and of the Helix and what's the space between them. you said this antenna is alittle forgiving on these details how much offset does it take to make it not function just inquiring. thanks

@nhansgoofyvideos7581 Жыл бұрын

I wonder if you use a wifi 6 AP and wifi 6 device would you get better bandwidth on the same 2.4ghz band?

@lohikarhu734 Ай бұрын

You might get a step drill for working on the sheet metal...they leave a bit of a chamfered edge, and don't "grab" when they go through, and you just drill to the hole size you need... Safer, and 'cleaner' !

@maosolny5856 Жыл бұрын

fridge

@skysurferboy 11 ай бұрын

Great project.

@ElectroEngineers 11 ай бұрын

Niceeee ideaaa. Using old frigde as panel and its watertight, excellent 😂😂

@shakaibsafvi97 11 ай бұрын

Hi, Amazing results and great effort in your design. Excellent work. You make the black art of RF antenna design look so easy. Can you also shed some light on how to calculate the Gain of the antenna ?

@dereksgc 11 ай бұрын

You can go to my website helical calculator, which gives you a gain estimation sgcderek.github.io/tools/helix-calc.html The formula taken from the literature that is quoted there

@SirAzazel 11 ай бұрын

Love the print on 1 GHz antenna, havent expected to see it at all. Hello from Ukraine my friend :))

@thirtythreeeyes8624 4 ай бұрын

What does it say?

@imbass8151 11 ай бұрын

the fridge was a visual flashbang haha. Love it

@spongerobert 11 ай бұрын

Super informative video. What kind of cable would you use for connecting the router to the antenna?

@Elfnetdesigns 11 ай бұрын

I forget the cable type atm but it's that small clearish tan stuff you use with sma / rpsma fittings, also since consumer wifi devices are not powerful you definitely want the cable run to be 50 ohm impedance, as short as possible with no tight bends, kinks or adapters and NO loops. The BEST option for a good wifi antenna is actually not an antenna but a wireless bridge radio set in client / station mode and used as an external high gain high power wifi adapter on your PC laptop. literally all it uses is a set of ethernet cables to interface it's PoE injector (power supply) inline to the radio and from your PC / laptop. Plant it on a tripod outside facing the direction your desired wifi signal is in and the rest is web based setup and connecting.

@synack_DCCBUS 11 ай бұрын

Another nice vid with good data thanks again

@Monothefox 11 ай бұрын

Do helical antennae couple to the electric or the magnetic part of the field?

@BatGS 7 ай бұрын

Greetings: I looked in the description 4 the External antenna mod on the router. I could not find by title. Which is it?

@DannyTheVito 11 ай бұрын

Awesome video! I have been looking for a solution for having an outdoor base station like that. How weather proof is the fridge? Seems like a great solution if you can prevent water ingress.

@dereksgc 11 ай бұрын

Been about a year and nothing got inside. Just could use a bit of an extended roof so rain doesn't get stuck on the door

@apimente Жыл бұрын

F a n t a s t i c Really goog Thanks for sharing

@ResistDemise Ай бұрын

Hey Derek I’ve been trying to design a helical for some time but I’m struggling with it. I know you said you eyeballed it and don’t care but how did you come up for the dimensions of the matching strip? I can’t find details of this online:( thanks

@VirtualizeThis1982 11 ай бұрын

Have you ever considered trying to build a DIY troposcatter system using cheap C Band LNBs and SDRs?

@Clancydaenlightened 11 ай бұрын

You only can gain so much improvement until the bandwidth needed needs a transmit frequency higher than 2.4ghz Problem is propagation, you want as low as takeoff angle to have dem waves travel as close to the horizon before they fly out in to space, also one that won't be affected by water vapor, trees, or a building It's also quite helpful for the wifi access point be at the highest elevation relative to area and devices connected Then use a 2.4ghz repeater to allow a slower network to fill gaps

@txfalkon2882 11 ай бұрын

awesome work bro. just inquiring incase we have two helical antennas for example lets say using this very one for 2.4 ghz, and we have them said by side but have them connected to the same cable feeding to the adapter will it improve on the reception stregthen or will it degrade instead

@dereksgc 11 ай бұрын

You would have to use a proper phasing network to make sure the two antennas actually work together instead of against each other. It can be done but it is much more difficult than just making a single helix a bit longer

@paranoidzkitszo 11 ай бұрын

What color/ paint is the Fridge station server box ? Looks very "'official"'.

@sylvestertettey2615 2 ай бұрын

what should the thickness of the helix conductor be??

@IOTConnect Жыл бұрын

If I wrap the copper wire in helix, around a 3D printed PLA tube, which has a pre defined grove in helical form, and super glue them together and keep that tube attached to the dish. Will that effect the gain of the antenna.

@dereksgc Жыл бұрын

It is probably going to work, that is how I made my very first helix as well, but I can't say how different types of PLA may affect the helix

@timothius9000 6 ай бұрын

@@dereksgc put a sample in a microwave oven (and a cup of water). the hotter the sample gets the worse it is for RF use

@em9594 11 ай бұрын

Now what's the 5 ghz WiFi helical antenna construction look like?

@tanasegabriel1899 11 ай бұрын

At what cable length do you use, you lose at least -3 dB. It is ideal to use a thicker and shorter cable. 1dB maximum loss with LCF1/2, but the disadvantage is that it is rigid and the plugs cost more. But you can use longer lengths, compared to thin cables. I use at least LMR400, 1/2 and for longer cable lengths type 7/8...

@Graeme_Lastname 5 ай бұрын

So how did you measure the VSWR and what was it?

@michaelmueller9635 Жыл бұрын

I guess corrosion might be a problem, because it no aluminum (some epoxy for the copper might help). Maybe next time you wanna try a quadrifilar helicoidal antenna ;-)

@jameshatton4405 Жыл бұрын

Hey can you use this Helix with the dish? And what distance are you covering and lastly is it line of site? Will trees cause a lot of interference?

@dereksgc Жыл бұрын

A dish feed should probably have fewer turns. I have several other helical antennas like this for various frequencies as dish feeds. 2.4 GHz WiFi will always be heavily affected by obstacles. In my case I'm only covering about 100 meters, but with trees and walls in the way. If you had a perfectly clean line of sight I'm confident you could achieve many km/miles of range

@BenCos2018 Жыл бұрын

*when you finally get tired of losing coverage in your room* lol nice build btw

@PixelOverload 11 ай бұрын

Is stripping the plastic off the wires necessary if there's no shielding to get in the way? Might improve the outdoors longevity

@dereksgc 11 ай бұрын

It most likely would be fine, but it removes one uncertainty factor. Each insulation may have different dielectric properties and a different effect on the antenna, but as I've demonstrated in the video helical antennas are so forgiving when it comes to design changes it probably would still work

@tobix8982 6 ай бұрын

Quick Question: I really don't have any scrap yards near me and I'd need to buy one online. Would a copper sheet or aluminum sheet be suitable for such use? And if not, what would I need to search after? And what would be the measurements for a 1.7 GHz Antenna (diameter, thickness)? Thanks!

@dereksgc 6 ай бұрын

You can use this calculator to give you the dimensions based on frequency, you can also scroll down to read about some of the values and design choices: sgcderek.github.io/tools/helix-calc.html If you can't get a sheet of metal, you can use any flat square/circular metal object, for example some of my antennas use the bottom of a large tin can cut out. A more unusual but still perfectly valid solution would be getting a metal dog/cat bowl, as long as the center is flat enough and large enough

@KeithFeickert 11 ай бұрын

Hi Derek, I noticed the helix_v5 models' default is 1700L, and not the 2450R that is in this video. Is it possible to have the values you used in the video posted in the description so we can use your calculator to edit the values in OpenSCAD? A thousand thanks! :)

@KeithFeickert 11 ай бұрын

After using a larger display, I could see that you included the proper values in the video (I just needed to look closely at a screenshot). Thank you! 🏆

@KeithFeickert 11 ай бұрын

On a side note: it looks like the bottom strut offset is placed at a value of 25 instead of 0 as shown in the video. Everything else looks correct, I think.

@dereksgc 11 ай бұрын

You can use the offset to lift the bottom strut if if gets in the way of the connector or anything else, besides the frequency+polarization, number of turns, and turn spacing, most other values don't actually impact the performance of the antenna itself

@skulbite 11 ай бұрын

Should try an iperf test to check it's try throughput

@MrMassmaker 11 ай бұрын

a really nice one! RSN PZD!

@ronaldrepolona 11 ай бұрын

question, for this setup do you use both helix antenna on each end? i mean from that station to your house?

@dereksgc 11 ай бұрын

no, other end is just a normal router behind a couple walls, this one helix is having to do all the work on its own

@sauravmodak507 Жыл бұрын

Bro what is the name of the tool you are using in this video to cut the metal sheet? I never seen it before

@dereksgc Жыл бұрын

it's just a normal manual sheet metal cutter

@MONEYCONCEPT27 3 ай бұрын

I have question for this video, in sessions performance setting, you made antenna helix for transmitter or receiver? I need answer from u, sorry for question 🙏

@dereksgc 3 ай бұрын

In the video when I was testing the speed, the helix was aimed at a router with a standard whip antenna, so you could say the helix was at the "receiver". Router with helix was getting internet connection from a router with normal antenna far away

@MONEYCONCEPT27 3 ай бұрын

@@dereksgc okey thanks for answer, Do you think this antenna could be possible for transmitter communication WiFi?

@dereksgc 3 ай бұрын

@@MONEYCONCEPT27 it could but it is not omnidirectional, only works well when pointed at things directly, and may violate EIRP power limits depending on your country

@MONEYCONCEPT27 3 ай бұрын

@@dereksgc I plan to design an antenna for WiFi communication as a transmitter, do you think a helix antenna or a microstrip antenna is better? I ask for your advice

@seanshay6573 Жыл бұрын

great video man

@coler154 11 ай бұрын

this is great, please show us the 5 Ghz version!

@frank20a 10 ай бұрын

Found your channel last week and I've watched pretty much all the content you've put out. Your content is incredible and you are providing the community with very good resources. Thank you! 73 de SV1TFB

@christopherjordan2787 11 ай бұрын

So for the point to point you only have the one helix at the ground station? Or is there a second antenna pointed at your fridge setup from the house router?

@dereksgc 11 ай бұрын

I only have one helix because the other router needs an omni antenna to cover the entire house, which means the performance is much worse than what it would have been with two helicals aimed at each other

@christopherjordan2787 11 ай бұрын

I'm impressed it got such decent performance and that's good to know. The video was very well made btw good job

@AronGreen Жыл бұрын

You should use something like iperf so you remove the internet as an issue. You can run a server at the base location and a client on your laptop

@emilianomarcle4875 21 күн бұрын

amazing video! i was comparing my results with your calculator and i think there is an error in the Half power beam width, the First null beam width and the Gain. Bhp = 52/[ (C/lambda) * sqrt( n * (S/lambda) ) ] , Bfn = 115 / [ (C/lambda) * sqrt( n * (S/lambda) ) ] , G = 11,8 + 10 log [ (C/lambda)^2 * n * (S/lambda)]

@dereksgc 21 күн бұрын

thanks for the heads-up, theres already one issue been opened on github about this, i've been putting off a complete overhaul of the website so i will try to get this fixed up during that

@ZincLeadAlloy 7 ай бұрын

The file you linked to doesn’t have the same base that attaches to the reflector, could you please post the exact one you showed on your video?

@ZincLeadAlloy 7 ай бұрын

Solved by changing the paameters around n the code, sorryabout that this is the first parametric (?) design I've encountered!

@testingsx 11 ай бұрын

6:45 =) Big Antenna with Big Description =)))

@WarMusic2022 10 ай бұрын

Точно!!

@shadyarian 7 ай бұрын

If you have a multi antenna router to connect these ones to, would it make sense to make 1 left polarized and 1 right polarized?

@dereksgc 7 ай бұрын

Probably, that way the router can work with the inverted polarization reflections. Left vs right hand polarization is for circular antennas more or less the same thing as vertical vs horizontal for linear, which is what MIMO antennas tend to use anyway

@timothius9000 6 ай бұрын

@@dereksgc all that destroys the function of MIMO, it's about getting the relative time-of-arrival of a valid signal and filtering out signals with a different time signature. the best information i can find for this is that the two antennas need to be a half-wave apart

@stevenclark2188 11 ай бұрын

If you have two of these with different chirality can you do MIMO? Is there something like a disk-yagi that would get you radial polarization so you could get 3 streams going?

@dereksgc 11 ай бұрын

Not sure how well MIMO would work with a directional antenna. If a circular signal reflects off something it inverts its polarity, so having both LHCP and RHCP could interfere with itself.

@timothius9000 6 ай бұрын

@@dereksgc if you used wifi5/6/7 with 2x2 mimo, with matching polarization on the 2 sockets, the router would be able to better ignore other signals/noise on the band increasing it's effective range much further. there are extra options not enabled by default in openWRT regarding this. obviously this would involve two dishes at each end, but plain helicals + mimo is awesome for point to point

@dereksgc 6 ай бұрын

@@timothius9000 Yeah absolutely, LHCP/RHCP MIMO would be the ideal solution, I just wanted a straight test of one antenna vs the other considering that they both promised more or less the same gain. One issue that comes to mind is dual-band operation on 2.4 and 5 GHz, the helix might not be very suitable for that, though there are dual-band helical antenna designs that have been proposed

@timothius9000 6 ай бұрын

you'd be better with devices that have 4 antenna sockets, 2 x (2x2) mimo (and 4 helical antennas looking like an array)

@eswnl1 Жыл бұрын

I was under the impression that helical could receive linear just as good as a linear antenna would. It would just pick both H and V at the same time.

@Elfnetdesigns 11 ай бұрын

linear will receive a circular polarized signal just fine, this is how many FM broadcast stations are set up so your stereos linear vertical whip / telescopic or horizontal dipole wire works. The thing with circular polarization is they work best in systems with "moving parts" like FM broadcast transmitter is static but your vehicle is not or an orbiting satellite is moving (tumbling) or not in geo where you may be static or moving around via car, boat, plane.

@kgsalvage6306 11 ай бұрын

I think that a metal lid for a 1 gallon paint can would work fine for the reflector.

@dereksgc 11 ай бұрын

yep

@rawexploiterp6951 Жыл бұрын

so i need 1700L or 1700R with dish reflector for NOAA HRPT?

@dereksgc Жыл бұрын

HRPT is RHCP, but dish inverts polarization, so you need LHCP

@tanasegabriel1899 11 ай бұрын

Change patch antenna to biquad antenna, higher gain but also better directivity. Then compare with the helix antenna...

@julesboileau 11 ай бұрын

is this antenna bi-directional ? if not, whats thue use ?

@dereksgc 11 ай бұрын

It is, antennas receive the same way they transmit, as long as they can handle the transmit power (which in case of 2.4 GHz WiFi hardware is basically nothing)

@x_CrossHair_x 2 ай бұрын

With any DIY Project. If you didn't cut yourself. (Then you did it wrong 😊) .. Thanks for providing the links to the on line Calculators (They will be helpful) I love the Refrigerator (Repurpose)👍

@txfalkon2882 7 ай бұрын

hello say i needed to make one for digital TV to mount on a dish what wave length is that

@dereksgc 7 ай бұрын

This will not work well for TV, the wavelengths are too large, you will have to look up your local channel frequencies but they tend to be between 500 and 1000 MHz, a helix would not be practical. If you have a very large dish antenna (2m or more) you can use a yagi antenna in the focal point, otherwise you are better off just building and using a normal yagi

@txfalkon2882 7 ай бұрын

Thanks for this it has cleared the confusion so for the tv channels the Yagi antenna will best option i wll give that short i have made some yagi before. @@dereksgc

@mathieudemeestere6326 11 ай бұрын

Hi, Im new to RF so quick question, What is the matching strip for?

@dereksgc 11 ай бұрын

It's to reduce the sharp impedance transition between 50 ohm coax and 150+ ohm helix. Arguably not really needed on receive-only antennas but when you're using it for transmitting you want to make sure it's matched as well as possible as to not damage the transmitter

@mathieu2109 11 ай бұрын

@@dereksgc oh that's cool! And how do you calculate its size then? does the calculator do that for you?

@dereksgc 11 ай бұрын

@@mathieu2109 yes it gives you all the numbers you need to build a helix, you just put in the frequency you want, number of turns, and spacing