can work too but more difficult to have enough strength to pull straight. Using the rotating power of the drill is no effort.

@@PoweredMeshtasticEurope True. I can pull up to 16SWG, but that's my limit.

@@PoweredMeshtasticEurope First of all, great video, thank you for posting. I do have a question, is there some way to "strengthen" the antenna, maybe some sort of PVC tubing etc just to make it more weather/wind proof?

thx

Great !

Thanks I'll try !

I keep your suggestion in mind for an eventual future video. Thanks

Nice of you. I'll see if I have time to make a tutorial on using Nano VNA but you can already find lots of these tutorials from others on youtube. This is how I learned myself...

Thanks for your comment. The pigtail which is delivered with the Heltec V3 is not a very high quality coax. I would suggest using a pigtail such as shown in my video instead. But technically you could do what your saying.

Any Recommendations how to tune it as NanoVNA comes with SMA i.e. is there suitable ipex-SMA adaptor that would allow tuning antenna that has ipex connector at the transmitter end?

I have personally stiffened the coax with a simple piece of electric wire (taped).

could be done but would require to move the Nano VNA on site

Or at least have the antenna in "free space" and not lying on the table. The proximity to whatever that material is in the near field will have an effect.

sorry to hear what happened to you. Thanks for the advice.

@@PoweredMeshtasticEurope Hah, while funny, he is right to some degree. I don't think your wire will cause it to break, but they can and DO, especially if you try to cut harder wire than copper, or larger diameter. They are little electronics nippers meant for .5mm and smaller. Trying to cut some like 6awg stranded wire might work, might break them. That's how I broke a set of my xcelite cutters. And when they DO break, it might be just the tip, might be a whole jaw! All that force goes somewhere, which ends up being turned directly into kinetic energy imparted on the part that breaks off. Which can make it move quite quickly, easily more than enough to pierce skin, or take an eye out. That's the same reason why it's extremely important to constantly 'dress' your punches and chisels. The end you hit with a hammer mushrooms out, and eventually a fragment WILL break off, and the entire force of the hammer hit shoots them out like a bullet! Same thing applies to these little cutters!

The coax does not "receive" (but is part of the circuit). Ideally the coax part should be 1 wavelength (1/2 wavelength is also ok. Other multiples will generate reflections). In practice it is difficult to have it tuned perfectly (there are so many factors : quality of the dielectric, thickness of it, impedance, reactance, etc).

a resonant dipole presents 50 ohms of impedance

print two

Omg really 😂

Yes sure, except you have to adapt the length of the two radiating elements in function of that 915Mhz frequency range (rule of 3 will work)

@@PoweredMeshtasticEurope And I should reduce the size of the coax wire a little bit. Thank you very much.

@@anlpereira the coax wire's length is not so important.

@@PoweredMeshtasticEurope thank you very much.

Yes ! The stripping i required to straighten the wire. Then The heatshrink will protect (against oxydation) and stiffen the wire.

@@PoweredMeshtasticEurope Thank you for replying - that makes complete sense👍

sure. But thickness will have an impact. In fact the thicker, the broader the bottom of the VSWR curve but not as deep. So you can choose to have a broader range antenna but not as good VSWR or a better VSWR with narrower bandwidth.

I would have to research these antennas a bit

That would be great

You're right. Ideally you should have a balun to get a perfect impedance match, without any reactance (capacitance or inductance). But this is out of reach of the common tinkerers and it works weel enough with that simpler approach.

I have updated teh description with the link to printables to download the stl file.

Thank you!@@PoweredMeshtasticEurope

If I find the time for it. But basically , divide all lengths by 2.76 (ratio between 2.4Ghz and 868 Mhz)

I do not know of anyone. But really you could build it yourself, you're capable !

Not sure what you mean ?

Yes, any coaxial feeding line does the job indeed (coax needs to be thick enough though for minimum losses)

What's your definition ?

@@PoweredMeshtasticEuropeHard to descibe without some background in physics. Pure resistor 50 Ohm has SWR 1.0, emits RF energy zero (but heat)

@@PoweredMeshtasticEuropeen.wikipedia.org/wiki/Standing_wave_ratio

Oh my. Antennas are rarely a simple 50 ohm resistor.