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.

Nice one! Thanks for the details and 'small' tipps!

Really neat innovation and experiment! Thanx for sharing.

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

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.

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 respect ppl doing the antenna stuff ... it's so unpredictable and easy to fuck up.

Sweet!

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...

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

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.

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.

Super video!

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.

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.

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

Nice job, need more bandwidth make the copper thicker, FYi I use copper tape on formers 10-20mm wide > Kaplah !

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.

Converting the holes at the top to slots would probably make bending and mating the tubes.

Perfect for 10km extension for drones it seems

You might want to use a small pipecutter for that tubing.

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?

Oh! What a nice build. I would wish a tutorial like this for a 137mhz build. Do you have any plans?

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)

That antenna looks great, thanks for your valuable lesson. I am wondering if a smaller version would be possible for 868MHz?

Too clever, by half. Without the plastic your link budget will increase by at least😊 10dB.

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 )

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?

@EngineerMeThis , Great video. Would we need an impedance transformer at the base of this helical, or is the coiled coax doing this job?

Put a chuck in the end of the former and you have an Archimedian drill

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?

💚

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.

*¡¡¡ ANDA YA !!!*

You could tinn the ends before feeding it through

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.

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?

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.

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.

You might want to look into the application of a tuning slug

Look Forward To seeing test results on VNA etc. Have you upgraded this to another version?

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!!

Good Work. Quite impressive. Just wondering what the gain of the antenna might be ?

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 :)

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.

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?

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

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

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.

Hello, compliments for realization. Have also the 137 MHz version?

what's the best antenna for digital tv broadcast reception?

@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???

Cloning keyfobs from 5 miles away?

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?

Could you use heavier wire and do away with most of the form?

Would this antenna work for TV signals ?? How can one make a killer TV antenna similar to this design Sir ???

Hello, If I ask, could you send the CAD file. Thank you.

Is there something like this for 137mhz?

Could you have used a slinky?

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.

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😋

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.

Have you tried placing the antenna into a 1.5 or 2litre soda bottle? Will it detune it detectably?

That would solder a LOT better if you Actually added some solder instead of just using brute force transfere

hmm.. wonder if I can make a 10m version... lol

This is RHCP or LHCP

could you please send the STEP file

I bet the center insulator is melted and causing a short circuit @28:30

Could you build me one of these for 300mhz?

what is qfh? do not know qfh.

What I dont like is the repetitive On Hold Music. Do you really need that?

bye bye background music.

Yet another UKpostsr overusing the words "actually" and "actual"! Sad

We’re all disappointed. This could have been a 2 minute video. Yer a ⏰ / 💵 artist.