"Build an Amazing QFH Antenna : Here's How!"
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- čas přidán 4. 09. 2024
- As Promised, 433Mhz QFH #build . In this video we take a look at #howto #build a #QFH antenna for the @tinygs and @SatnogsOrgProject #communities, this #433mhz band antenna is a custom dielectrically loaded antenna which is the reason for its size reduction. this is a wanted attribute since some opperators do not have to option to install large antenna's outside the homes.
So if you are looking for the #perfect #qfh #Antenna to #track #cubesat #weathersats or any 433Mhz eqiupment this is the correct project for you.
This is the first in a series of antenna's aimed at the Satellite tracking community and will be a work in progress untill the prefect option is found.
Files are made available on thingverse.
Amazon links
1) Coax RG316 amzn.to/3Syml7N
2) SMA Connectors and Crimper amzn.to/3ISZoce
3) Copper Tubing amzn.to/3KB0cnr
Files and Calculators
1) ThingVerse STL Files www.thingivers...
2) QFH Calculator used jcoppens.com/an...
Community to track Satellites
tinygs.com
t.me/joinchat/...
Not being a radio guy, I just printed the print in PLA, and just used ordinary multistrand electrical wire… soldered ends together on the bottom.
Then just soldered center and shield of coax to the wires on top (as shown in video).
No balun, No tuning or anything, I have no instrument.
Then connected it to TinyGS Lora Satellite Groundstation, and it just works 😊. Receiving 20-80 satellite messages daily 😊
(It is just hanging inside, in front of a window, using a nylon string) Receive only.
Thank You 🙏👍😊. Best wishes from Norway
Make Slotts in stead of holes in top where solder connection is, so you can do assembly on your tabletop, and slide it in then roll tubing in place . Add end caps to seal it all up
Neatest antenna i ever found was about 60 years ago. Being a boy i was attracted to a long abandoned house. A Mannion in its day, i was quite amazed that it sat abandoned. Beautiful wood work and antique furniture a victrola which when cranked up played Caruso, a voice worth hearing even on old vinyl or baklite. As i grew bolder i worked through each room, gas lites still worked, the library contained many volumes, fully equipped kitchen marble shower with ma y heads extended to a sauna, ypstairs bedrooms and office. The attic held a surprise. A hidden room with a great huge light green transceiver, the reciever used long wires which ran. The length of the house, the transmitter a crank up dipole. Why hidden you ask well seems i had stumbled into a german spys home he was also a saboteur as the explosives in his work bench would confirm, and the files marked secret us navy, or the map of a local aircraft plant. So it was quite the adventure . Lucky he didnt boby trap the place as i would not be able to share so many years latter.
Dang old folks ramble and never tell what they started on about
@@trueKENTUCKYI know reading comprehension is likely a challenge, but don’t give up!
Sorry guys, I told the story because I'm old, it was a hell of an ad entire for a kid, those who were with me are dead. Be thankful I didn't tell the whole story. A disappearing family, 250 000 dollars in confederate money, luggage in attic packed for trip in 1912, never left the house, thousand in travelers check didn't make the trip either. Mysteries
@@jwc4520Wow. Can't wait to hear your whole adventure.
Should do a youtube vid telling the story.
I have no idea how I got here but this is insanely cool.
I didn't realize plastic has such a big effect on electricmagnetic fields
Haha youtube works in mysterious ways... 😂 glad you find it interesting. When I originally saw this myself I was shocked.. even wood, has an effect but far less. And don't get me started on carbon fibre. I still suspect there is oppertunies in carbon fibre antennas, it's just not understood fully yet.
@@EngineerMeThis Carbon fibre is super weird being a composite lol.
mixed carbon, plastic and resin.
catching itself off course can be wildly conductive depending on the structure but it's stupid hard to work with.
So we mix it...
Graphite however.
I just found this video now! Very interesting stuff! I am a Mechanic (35+ years), and I also repair electronics, computers, houses, you name it. I also do 3D work in 3DSMAX and AutoCAD. I still need to get myself a 3D printer though!
Have a great day! o7
Carbon fiber is a conductive material. It's used in a lot of things such as ion generators. Or ozone generators.
@@EngineerMeThis try using pre-preg carbon fiber. There are some composites like innagra that mix polyethylene and carbon fibers. It's easier to handle and then you only bake if using pre-preg in a common oven or use a mould and resin infusion.
Thanks for sharing. When I make antennas, I experiment with different diameters forming mandrels, like a baseball bat. Start with the larger diam, wrap a turn and then see what diam it pops out too, repeat with smaller sections till it turns out the correct diam. In a minute typically I am good and I use tape and a sharpie to mark the perfect diam forming for my desired antenna.
I respect ppl doing the antenna stuff ... it's so unpredictable and easy to fuck up.
If you crimp and solder the ends it would keep pressure and prevent the tubing from collapsing. You can also add water or a very fine sand and solder. Makes bending a lot easier
18:00 before soldering you should bind the ends with copper wire, looping it around several passes like thread and binding the copper ends together. Then when you solder, you have much more copper in contact instead of using the solder alloy as your conductor, which creates resistance. You will also use less solder and flux. To combat the heat from destroying your print, capping the other tube ends with hot glue and then dipping the whole thing (except the soldering end) into a water bath bucket. Solder as close to the water without that inner inch of wire-wrapped tubing touching the water, so the rest of the tubing acts as a heat sink.
More copper surface area would also mean more heat dissipation from the soldering iron, making soldering more difficult, good soldering work anyway. His would be worse than it already is.
@@rootbeer666 That is not quite the problem. He needs a higher power solder to apply it a very short time and use plenty of rosin flux. I learnt it the hard way myself after many burnt fingers, melted cores and failed chasis weldings.
Indeed the case yes. The ideal solution is a custom made pcb where the copper tube ends are screwed to clamped to the pcb and pie machine and termination is done of that pcb
@@miguelangelsimonfernandez5498 more power is always the remedy for soldering taking too long, also a cobber tip with thermal inertia could be a benefit. It's all about dumping the heat fast 🧐🤓😉
@@miguelangelsimonfernandez5498 In the past when components were large the go to soldering tool was a Gun type with the resistance loop element. Lots of heat in a small location, much more than you can get from modern cartridge heated irons designed for small components.
This makes great sense. I was searching 3D wire bending machines to create really accurate helix's. There didn't really seem to be many ways to rapid prototype QFH for different frequencies and experimentation. 3d printers to the rescue! as for 144Mhz QFH they are too large for the 3D printer, probably...
Just saw your QFH video. Suggestion for a different core/bobbin for the antenna is use your gray air core design but add in supports as you progress upward. You could try to create an elongated slot to pass the wire through and then rotate the support so that the wire is in contact with the support only on the leading and trailing edge to minimize dielectric contact area, then glue inner edge to the bobbin.
Thanx for the tip. I agree that reduced contact would help the performance, but the point of this antenna was to take advantage of the capacitive loading to reduce the overall size. I can remove all the core but would have to increase the physicall size by 40% to resonant at the same frequency
Really neat innovation and experiment! Thanx for sharing.
Converting the holes at the top to slots would probably make bending and mating the tubes.
When connecting the coax "exposed" part to the tube you should have heated the solder on the tube first than attach the coax. Applying that much heat damaged the internal insulator which is why is was not getting the best signal. Also if you had applied some fresh solder on the tip of the iron it wold have worked better. There is a whole science subject just on soldering and overcoming thermodynamics of the dissimilar metals.
Hey, Thanx for comment. Fully agree the approach to soldering directly to the tube is wrong to begin with. I need to layout a PCB that the copper tube can be screwed to as a termination and the Coax connected to the pcb. This will also allow for tuning the impedance better.
@@EngineerMeThis Yes that would be the ideal solution, but for the prototype the way you did it proves the concept works. Now for some refinement. 👍
Nice job, need more bandwidth make the copper thicker, FYi I use copper tape on formers 10-20mm wide > Kaplah !
Well done! Thanks for sharing.
It's much better to use a much larger wattage soldering iron when soldering large wires, tubing or other metals. It's better to apply a larger amount of heat for a shorter amount of time for less damage to surrounding areas, plastics etc. You will also get a much better solder joint. It's also possible to better use heat sinking with a larger wattage iron than with the small ones. With a small iron you can sink out too much heat to get a good solder joint.
Nice one!
Thanks for the details and 'small' tipps!
I would have used copper tube cutters to cut the copper, and maybe a redesign at the top of the plastic cylinder to make the curve easier . Oh and make the holes slotted that would make insetion easier.
Too clever, by half.
Without the plastic your link budget will increase by at least😊 10dB.
Agreed and your physical size will increase by 100%. As per normal antenna performance is a balance between size and performance
Awesome! Now looking to buy a 3D printer.
Put a chuck in the end of the former and you have an Archimedian drill
Hello there, Greetings from Christchurch, NZ .... Thanks for a Super Interesting vidclip ..... I am ALAWYS Really Interested in UHF Antenna .... We work on UHF CB at around 477Mhz and your Design is actually quite close to That Number .... Best to You and Yours .... Cheers .... Keith
Thank you for the video! I appreciate your efforts to create a simpler way to make this complicated design and hope through iteration you can find a design that can meet your specifications. I also wish to build a QFH for a TinyGS setup and have been attempting a eggbeater design, but not have luck tuning it. I noticed your Thingyverse account has a egg beater design that is similar to the one I'm building and was curious as to the design parameters for that design. Thanks again!
I really like this video and the design of the antenna and I always wondered how an antenna like this would work in a where there may be restrictions on outside antennas. I also like the feed point and how the connection would look. I have seen some great pointers on the soldering part and I agree with building up the solder on the shielded part on the connection point with coax shielding of coax is made. I think when it comes to making the area just a bit larger, would it be a good idea to maybe try using a something like very small flat piece of metal wrapped around the shield to make it easier to solder the connection and reduce the overall heat generated from the iron. Thanks for the video de N1ZW Rob.
You might want to use a small pipecutter for that tubing.
Perfect for 10km extension for drones it seems
You might want to look into the application of a tuning slug
Indeed. my next version will likely be more of a production approach with internet termination PCB, Balun, Pi circuit to allow performance tuning.
Have you considered using strips of copper sheet? Companies that make/sell continuously formed copper roof guttering start with rolls of copper sheet, wide enough to make guttering. You can buy a length of this and have a sheet metal workshop cut it into narrow strips. These narrow Cu strips are lighter and easier to wrap around a QFH former than Cu tube.
Thanx for the feedback. I have considered something similar that I think could be easier to work with and that is adhesive copper type
@@EngineerMeThis But then you would need 100% support of the tape, and that would be something else to make. It is likely to add dielectric losses. Real 3M copper tape is $$. The adhesive will fail after exposure to the elements. You might be getting the impression I don't think tape is a good solution. Sheet Cu is not strong enough to be self-supporting like tube. I suggest using PCB (Cu removed) disks with 4 slots cut evenly spaced around the edge of the disk, and a hole in the centre. Mount the disks horizontally on centre support tube spaced at say 100mm. The spacers could be plastic tube sleeves that slide over the centre tube. Thread 4 strips of Cu strip through the slots and rotate (then glue) the disks to form the spiral. No special tools or materials required. Aluminium strips would reduce cost and be almost as good as Cu. Even if a QFH was made with Cu tube, the fibre glass disks (which don't need to be disks, but easier to explain) would physically stabilize the antenna.
@darrenconway8117 I fully agree with you. but I think you may have missed the point that this antenna is being deliberately loaded with the plastic. The plastics capacitive effect on the antenna causes the antenna physical size to be smaller for the same frequency, if the plastic was removed the antenna would have to be 20% larger in size to be resonant at the same frequency
@@EngineerMeThis I got the point, but that capacitance loading may also bring with it dielectric losses that offset the smaller size benefit. Also, just reducing the size by itself will reduce the antenna output, all else being equal. It is good to try different things and ideas, but equally important to quantify the results. My old professor used to say it ain't true if it ain't measured.
Super video!
Super!
Oh! What a nice build. I would wish a tutorial like this for a 137mhz build. Do you have any plans?
It's in the works! trying to accommodate people with 220mm build volume so making it modular
That 1/4" Tubing should be "Ridged Enough" to hold it's shape.. No need for the 3D Frame other than to help form the Elements perfectly... (Cut Slots) top and Bottom to Slip your Formed elements out after forming. (only thing) you will have to (Cut) and solder the ends at the bottom as well when installed into it's final Mast.. (Nice Idea) this QFH should perform the best for the TinyGS 👍 It will have a Perfect Radiation Pattern for Satellite RX. I use one like this for NOAA at 137 MHz (Very happy with it)
I agree with everything you saying, just remember the point of this project was to dielectrically load the elements with plastic to reduce the overall antenna size. So if I remove the plastix the antenna will no longer resonant at 400mhz. But your points are still valid and I'm working on version 3 so will def be taken into consideration
@@EngineerMeThis I hope you create a video Showing it's Performance and Resonance with your VNA. Along with a 3D printed Helical Radial Former (and willing to share the files 🙏) I plan to make one to hope will resonate at around 425Mhz ... But I cheat and use elbows for the 90 degree bends.
A forming frame (for one Radial at a time) would be slick. (Subscribed & Notifications are on) So... I'll be Waiting..👍📡73s
The dielectric of plastics differ dramatically on the chemistry of the plastic it’s degradation products during melt fabrication and the stabilization and or fortification that changes the die,extrications constant!!
CA or Cyanoacrylate glue is "super glue." Fun fact, it was invented while trying to find a way to attach iron sights on guns during WWII.
Nice use of 3D printing. I've been doing a lot in 3D printing and just now getting into ham radio/RF hacking stuff. Keep up the good work.
Great building! Thanks!
You could tinn the ends before feeding it through
No copper tubing cutter? The Dremel does work pretty fast but I am not a fan of the dust. When soldering the cable to the copper tubing, it may be better to heat the copper side first to get it warmed up then add the shield connection while moving the heat over to both cable and tubing?
If you don't want to have plastic print the mandril in PVA and dissolve it out.
Orif your going to need support, I'm guessing if your messing with radio you have a job so get an IDEX printer and print permanents in PLA/PETG and print the bits you don't want in PVA so you can dissolve it later.
"SOVOL SV04 IDEX" cheap nasty bed slinger but it will work.
Hey. Thanx for the message. That would certainly work if that was a concern for this antenna but the point of this antenna was that the plastic dielectric constant us used to make the antenna resonant at a lower frequency. So if I removes the plastic I would need to increase the antenna size to get to the same frequency.
really beautiful
Sweet!
Yes, the PLA and ABS plastics do have too big losses at UHF and microwaves. One option is to use Teflon with much smaller losses but it is expensive. Maybe one could combine them with an airy PLA support and small Teflon wire holders? OH2BLO
would a teflon tape (like you use to seal plumbing threads) lining be usefull? Using the current print, just a layer between the PLA and the copper tube
@@MrFadjule I doubt that. The plastic structures are near the antenna wires which interact with the material strongly due to their dielectric properties, just like in coax cables. Coaxes are made of various low-losss plastics. Some of them might be even better for this antenna. The wires should be as far as possible from the lossy plastics, a thin layer of tape is not sufficient.
While both of you are correct in antenna theory, the point of the plastic here is to make as much contact as possible as im using the dielectric loading of the plastic to impact the physical size of the antenna required at the desired frequencies, this antenna physical dimensions is 20% because of the loading effect @433mhz then what it would be if the plastic as not there.
@@EngineerMeThis I entirely got it. However, the losses of some plastics are significant and can not be ignored.
Seems like a difficult filament to print but there's a blend of PC and PTFE filament you can buy
Thank you so much for this video! I will try to make this antenna in future, also could You try making 3D printed QFH antenna for 137.5 Mhz if its possible?
Hi @Dario, I can certainly try but it would certainly be needed to be printed in a couple of parts as that antenna will be rather large !
@@EngineerMeThis Thank you for trying making 3d model of antenna i doesnt matter if its going to needed to be printed in more than one part beacuse i already tried making the antenna and i failed it :( it really hard to make it but if You could try to make one it is going to be easier for me and a lot of people that either dont know how to build larger QFH antenna.
Great project. What was the dielectric compensation factor for the design please. I want to make one for 982mhz
That antenna looks great, thanks for your valuable lesson. I am wondering if a smaller version would be possible for 868MHz?
Indeed. It will, in a next video I'll.be making a copper wire version for installation as telemetry radio in a STEM rocket.
From looking into it a bit the helical antenna would be very directional and is supposed to have higher bandwidth, but for some reason this one doesn't have higher bandwidth. Is there any comparison with a patch antenna? It seems you could make a patch antenna from a cut up beer can that would have coverage for the whole sky with less gain, but would be much more directional in the right way than using the dual band or 1/4 wave antennas recommended on the tinygs site.
Hey, I think you might be mixing a normal direction helical antenna and a QFH helical antenna. A Normal helical (which is another video on my channel ) is directional and very narrow beam. The QFH antenna has two coils in either 0.75 or 1 wavelength. This is a very omnidirectional antenna and nor comparable to a patch or normal helical antenna
@@EngineerMeThis I made your antenna design but ended up resonant at 402mhz with narrow bandwidth. It is improving reception on TinyGS and is still picking up some satellites on 433 but is doing best on the 400 mhz
@@GuyMasong1 Thanx for trying it out, I agree it tends to be much narrower then expected. but on the freq side, thats by design. if you have a wide spectrum to cover like 400 to 440mhz you want to be on the low side and being on the high side means you wont get any of the 400mhz freq. the issue as you stated is the narrow nature.. im testing new designs with better efficiency and wider band. so stay tuned.
Look Forward To seeing test results on VNA etc. Have you upgraded this to another version?
In the process of the next ones that's abit more refined
Hey there, thanks for your hard work on this! I'm wondering if it's possible for you to modify the STL so that the holes at the bottom where the copper tube is fed in again are open-ended. It would make it a lot easier to bend the pipes in. I tried doing it myself but didn't have much luck. Would really appreciate your help with this!
* Maybe if possible also provide a STEP file please.
Hey, I can do so, I found it easier just to cut them open after the print has completed. Cutter into open slots instead of holes.
Would this antenna work for TV signals ?? How can one make a killer TV antenna similar to this design Sir ???
I'm not sure. Depends on the frequency of the specific channel you looking at. Not a wideband antenna
@@EngineerMeThis Got it Sir. Look forward to see you make some deep fringe TV antennas. Nice video too.
Very cool! I'm curious though, did you do any testing to see if different brands of PLA or PETG (I'm assuming that's what you printed the frame out of?) effect the resonate frequency outcome? I.E. do we need to use the exact same filament brand and maybe even color that you used if we make this?
Hey thanx for message. I have used PLA Here ASA might be good option for outdoor use. I suck at printing PETG so still need yo try that. With regards to color. Generally the worse color is black as they tend to have more carbon based pigments but only testing will tell with other colors and materials
@EngineerMeThis , Great video. Would we need an impedance transformer at the base of this helical, or is the coiled coax doing this job?
Hey 👋 thanx for comment. The coil is ment as a choke. The antenna is suppose to be very close to 50ohm ideal match as is but, I have tested it with a external wire 50 to 50ohm balanced to unbalanced balun and works great
*¡¡¡ ANDA YA !!!*
I just built this and mine is tuned to 427mhz when following your instructions and hooking it up to my nano vna. Are you still going to make a video on how to tune these antennas? What do i need to do to get it up to 433mhz on the dot?
That would solder a LOT better if you Actually added some solder instead of just using brute force transfere
Lol Thanx Pete, it's a heat transfer issue. Copper pulls too much heat away from the solder to melt point. But thanx for the comment. Hope to see your version soon
Thanks for the video and the QFH former stl, looks great! Do you have a recommendation for how to scale it if you wanted a different center resonant frequency? I'm planning on building one centered in the satellite section of the amateur 70cm band ( ~ 436.5 MHz )
This antenna was ment for the 401 to 440mhz band as is and ended up around 419mhz mark with narrow band. on the thingverse page you will see the calculations used, it was actuall centered around the 450 to 460mhz mark if I recall to compensate for plastic. I suspect designing it around 470 to 490 region will get you closer. I am still working on this antenna and probably not to difficult for me to adjust this design to a aimed 430mhz version. also trying to see how to size it for 137mhz but at this stage it will end up in 6 different prints lol
@@EngineerMeThis An idea: make a design that minimizes the plastic i e the dielectric loading, in a way that lets you calibrate (or "analyze impact on") the frequency by intentionally adding dedicated pieces of plastic. Would be interesting to be able to predict center frequency better, but adjustability is even better(?). Also wonder how small (and thus portable or attic-hidable) it could be made with maximum loading (with common materials).
Any way: great video, even more inspired to make one now! /SM7UID
To clarify: I mean printing and adding small pieces of plastic of controlled sizes, is way easier than rebuilding/reshaping/resoldering and connecting any of the copper parts, so it would be an easier experiment testbed to measure the impact that different amounts (a wide range) of plastic has on the center frequency and bandwidth, and even how it matters WHERE you add it.
Then you could try to make one as small as possible.
Another idea: I guess you could load it dielectrically even more by pouring molten plastic into the inside of the pipes (before bendning) ?
I wonder if you could hybridise this with a magnetic loop design - with a variable capacitor to tune it. Rather than trying to lower the Q to give wider bandwidth, use it to your advantage, getting a lower noise floor. G7DMQ
I tried printing this in one go with a skirt. Around the halfway point it seemed like the printer head was bumping into the model or something as while printing the spiral arms, would violently be pulled then snap back. At times I had to physically had to hold the model in place to print it.
But it did finish and it looks great, except for a small scar in the middle that occurred before I started steadying the print. Perhaps a support tube printed around the main print could help this? I haven't tried that yet, but thinking about it.
Nice design, though, thanks :)
Ya its a tricky beast, one way to deal with it is to enabled Z hop in the slicer so that the head is raised between printed areas
@@EngineerMeThis I will try that!
That worked! And I slowed the print speed down. The whole thing printed beautifully. No glue required!
Good Work. Quite impressive.
Just wondering what the gain of the antenna might be ?
This Antenna does not have alot of gain to speak of and you don't really want it to either becuase that would mean it's somewhat directional and the point of QFH Antenna is to be omni directional antenna.
@@EngineerMeThis but this is a directional antenna isn't it ?
Its a helical antenna right. I thought helicals are directional ?
@shakaibsafvi97 the Helical part refers to the circular polirization of the coils around the core. But the propegation pattern is omnidirectional in nature. It has a slight directiveness towards the top of the antenna but it's is not enough to be determined as a directional antenna like the video released today ( actual helical) that is very directional.
I wonder if the shortening of the antenna elements through the additional loading that the plastic former causes, is what is leading to your narrow bandwidth? Loading an antenna will increase Q , which reduces BW, in general. Does your BW improve if you reduce the loading and make a more full sized QFH?
Hi Wayde, Spot on. the plastic loads the antenna to a point where the diameter of the conductor has little to no impact, this makes the antenna harder to tune but also rubust to interference, I have tested this by slowly cutting away plastic that was not needed structurally and the center started to shift. so alot of trail and error testing is needed for this to be perfected in the desired freqeuncy range.
@@EngineerMeThis I fully agree with VA3NCA's conclusions. I would suggest avoiding the printed skeleton in the finished antenna although I see the advantages for preforming the spirals. To that end you might consider a central backbone with Tefon standoffs placed at suitable intervals. As you may know Teflon is ideal for higher frequencies with low dialectric losses.
Hey Rob, Thanx for the message, I appreciate the input, just to recap the point of this antenna is to reduce the overall size of the antenna, this is achieved by loading the antenna capacitively. If i Use Teflon and reduce the antenna to just the core im simply left with an antenna that needs to be twice the size to be resonant at the desires frequency.. in otherwords, if the plastic is removed from this antenna it will resonant at 465mhz if not higher depending on the conductor used if the same size was kept.
@@EngineerMeThis How about using the plastic only as a jig and filling the tube with a slow setting resin, bending it using the jig before it polymerizes and later removing the jig?
so why use the copper tube? you printed a beautiful frame. Why not use aircell7 instead of the copper pipe? aircell is a closed surface so exactly the same effects as the tube.
Great point. The original idea was simple 1.5mm copper wire. But bandwidth was limited. So tried copper tube to see if it would increase bandwidth since the inductor was larger but due to the loading seems to have little effect. New Version I'm working also uses copper tube. But it's to keep its form without the need for mold.
Cloning keyfobs from 5 miles away?
ufb
Good engineering job!
I am always looking for an antenna, that meets the requirements and is small enough for neighbors view.
73 de Peter, DG8DZ😋
I've been consulting for a ca startup developing long range sky hop communication for sensor networks. Bounce rf off ionosphere. We need to find an antenna design that is as small as possible, broadband 2 to 10 mHz, with some gain 5-8dB. Any ideas?
Hi Kurt, Thanks for the comment. My first reaction is 2 to 10mhz seems very low for that application as the lower frequency would have less trouble to pass thru the ionosphere then let's say 5.8gjz or even 27ghz but you have other disadvantages obviously related to freq and link budget. And the antenna being directional to focus energy would make sense. But the challenge is that that freq you wave lenght is so large to make an effective small formfactor antenna is asking alot. First question would be what is the Transmitter output power ? and seconds a loaded quadratic loop antenna is the first thing I would test but it's not directional
"small as possible" with 5-8dB gain from 2-10MHz (not milliHertz I assume) is a physical contradiction... I'm assuming you are not a comms / RF guy (no offence)? A google search for HF antennas will give you thousands of possibilities for antennas, again because of the wavelengths "small" and "reasonable gain" don't come as a pair sorry. You could start the experiments with HF helical whips as used by hams and 4WD HF users. A quarter wave vertical on 2MHz is about 121ft long, on 433MHz it is about 6.7 inches.
@ingmar M you had me going there for second. I saw the comment notification on email but it does not show context around where you posted this only what video. And I couldn't understand how you got to 2 mhz for a 433mhz antenna video. Untill I saw you are replying to someone in the thread. Lol
Have a look at Magnetic Loops. They give about the best performance to size ratio. I use a 1.5m diameter loop on 80m which works really well.
The place you solder, would you be able to wrap the sections with a thin gauge wire and then solder them or would the loops create EMF issues?
I suspect if the copper wraps is covered in solder into solid mass then should be fine.. the correct approach I think is to make a termination PCB. Will make tuning easier
Can you share the editable .sldpart? I'm a Solidworks novice and cannot figure out how you did the swept feature with the shape. I'm attempting to redesign it for GPS L1.
@EngineerMeThis just printed and put together the wrongest way possible... Hahaha still work's excellent for receiving and decoding Radiosonde weather balloon's!!!!! Excelent work!!! Do you have the stl files for a top cap and bottom bracket of some sort???
Nice work!
@@EngineerMeThisHi! The QFH is working flawlessly!! I asked the guys who printed the antenna for me to create the top and bottom(for tripod/screw mount) covers! I have the .STL file if anyone wants it.
@@juanjocastillo i would love the stl files!
Abshire Falls
💚
Hello, compliments for realization. Have also the 137 MHz version?
You are not the first person to ask this, I'm looking at it. The issue is size. You would need to split and print this antenna in 6 pieces with the current design. So I'm working on the princple to see if different method can be used
👍@@EngineerMeThis
A 137MHz version would be fantastic. I appreciate the step-by-step video. Thank you.
what's the best antenna for digital tv broadcast reception?
What's the intended frequency of the channel you looking for and do you know if it's digital or analog signal
Katelynn Well
Lockman View
Schimmel Summit
Could you use heavier wire and do away with most of the form?
This antenna is made out of copper tube. Why are you suggesting wires instead?
@@EngineerMeThis so why is the large plastic form needed -- why isn't the tubing self-supporting?
@Mr Techie may have missed the into portion. The point of the plastic is to load the antenna capcitivly to make the antenna physically smaller. Without the plastic the antenna would need to be 40% larger to resonant at the same freq
@@EngineerMeThis thank you.
Hello Sir i need you help with some clarity i am trying to make a Helical antenna for 2.4 Ghz band (2400Mgh) but the calculators on the internet seem to give different values for the different measurements and diameters. And the other is am having some dish old huge dish laying around so i also want to make a helical antenna for digital Tv setellite channels but for this i have no measurements. is it okay if you could guide me on this. for my builds i wont use 3D printed frames I will use simple plastic in center. Thansk in advance
Could you have used a slinky?
Hey, Thanx message. No a slinky would form a different type of antenna called a helical antenna. And I plan on making a video on that soon. This antenna has different radiation pattern then helical.
@@EngineerMeThis Thanks , I'll watch for it.👍
Would this be able to download images from the Meteor M2-3
I bet the center insulator is melted and causing a short circuit @28:30
If that was the case I would have seen it in the test results
@@EngineerMeThis Perhaps the effect on the test result is minimal? I would short it with a jumper wire and see if the result is still the same. If a wild swing on the result took place, then maybe you are correct and no shorting on melted insulation?
whats the use of a QFH at 433Mhz? I am interested in building a QFH for NOAA APT and see some Space pictures but I don't recall what this antenna would provide at that freq.
I have built it and use it on my TinyGS. Receiving 20-80 Lora satellite messages per day.
@oljobo I looked up tiny gs and Lora. Neat project but not a lot to do if it's just packets of satalite heath and status.
@@tratzum yeah true 👍😊
what is qfh? do not know qfh.
quadrifilar helicoidal antennas
@@EngineerMeThis thanks for your information.
Hello,
If I ask, could you send the CAD file.
Thank you.
In the description
hmm.. wonder if I can make a 10m version... lol
80551 Ratke Turnpike
Is there something like this for 137mhz?
Lang Glen
This is RHCP or LHCP
RHCP
LOL.... Karens for neighbours 😅
Have you tried placing the antenna into a 1.5 or 2litre soda bottle? Will it detune it detectably?
With 3D printing you could form wire guides for the co-ax so that you just push it through the holes and it bends 90 degrees gently.
Reed Parkways
could you please send the STEP file
The solid works file is already loaded
Rahul Expressway
Could you build me one of these for 300mhz?
What usecase do you have for 300mhz ? You should just be able to scale the size larger for 300mHz as a quick fix
@@EngineerMeThis used for SATCOM
Allen Cynthia Young Paul Anderson Richard
What I dont like is the repetitive On Hold Music. Do you really need that?
Lol working with what's available to me for free. Hopefully the elevator music lead to good place where I can buy music for better production
@@EngineerMeThis Dont use music at all.
Brown Jessica Jackson Jeffrey Miller Linda
bye bye background music.
Yet another CZcamsr overusing the words "actually" and "actual"! Sad
Lol thanx for taking the time comment, you have actually made my day. Cheers 🍻
We’re all disappointed. This could have been a 2 minute video. Yer a ⏰ / 💵 artist.
I don't understand how can nobody be disappointed? It's in the name... nobody.
@EngineerMeThis1 seems he's saying the video could have been shorter. I prefer the how-to content to be there, and use the double tap fast forward to push through info I don't need. Thanks for taking the time!
in czcams.com/video/OJy-XjGYlGw/video.html you show a guide for turn the wires . Can you put the stl on thingiverse? i,m interesting on that sistem for buildld an antenna for tinygs mesh. 73 EA8DEC