Meshtastic (LORA) range test : Dipole antenna vs out-of-factory antenna 

Nice!

So, how did the 3-node network work out? Best regards from Brasilia, Brazil.

Yes I thought about that too. To be tested...

sure. It is also a nice project to build its own antenna.

The antenna was built for 868 in previous video.

@@bjorn2625Indeed.

Thanks. I do not sell antennas. It is not hard to make it yourself and it is a fun learning process.

LORA frequency (868Mhz band)

Because I'm the only one in Brussels right now...And I checked the received messages by the base station

Merci. Quel chance d'etre au soleil a Antibes, mieux que la Belgique...

for a HAM user emitting watts of power, you most probably need a licence. For LORA/LORWan, the 868Mhz band, as far as I know, is licence free to use at up to 20dbm (100mW). This frequency and 433Mhz are licence free (under power limits) to be used for IOT and drone use for example.

Thanks will pay extra attention to radio strengths and not boost over these numbers you stated. 2 heltec units are ordered last week, so hope soon to play with it.

Yes. I forgot to mention it indeed. So actually we could expect better range with slower-longer range settings

I tried the range test functionality with mixed results. It does not work fully as far as my experience goes. I might do a video about this "weakness" in the meshtastic app.

@@PoweredMeshtasticEurope I tried with the latest firmware, seemed to be ok thou tbh I didn't fully analyze the logs, but it did send/rec until I moved about 1.3 miles apart then it started missing a few. (heavy pines nearly the entire way between nodes)

But alors you speak french ! :)

That could be caused by many different factors : your environment, interferences, what frequency you use (is this frequency "polluted" by other uses around), etc What frequency do you use (433, 968, other ?). What antenna did you try and what meshtastic board ? Maybe you radio module is faulty ? (could have happened if you powered your device once without an antenna connected on it)

@@PoweredMeshtasticEurope I really have no clue and will surely repeat my tests soon. I am using EU868 on two T-Beams and as far as I remember I tried the tiny stock antenna, two bigger ones from Amazon that seemed to perform well earlier (good SWR too) and a DIY moxon antenna. I actually had good reception amongst houses up to 800-900 meters away but then in the forest with a better line of sight I ran out of luck. I actually did turn on the devices without an antenna by accident a couple of times but so far they seem fine. Or is it a GIVEN that turning them on without an antenna will instantly fry them? Will they still send, just badly (which might be an explanation) or will they stop working entirely if that happens (then they are still fine)?

@@UnknownUser-pf9rk - Powering the Meshtastic device without a proper antenna load could damage the transmitter. The device will appear to function but there will be little or no transmitted signal. I"d try a new LoRa device.

@@Liberty4Ever Like I mentioned it has worked up to at least 900m. Would a damaged board still do that? What about those horrible tiny stock antennas with horrible SWRs? Wouldn't they also damage the board?

@@UnknownUser-pf9rk - Certainly, the cheap antennas that have a dead short could damage the transmitter, and probably the antennas that are an open circuit as well. Transmitter damage can vary. Sometimes the final drive transistor is completely destroyed and there is no signal transmitted. Other times an area of the semiconductor is damaged and the transmit power is degraded. Slightly Different Topic: Ironically, power FETs are usually more sensitive to electrostatic discharge damage than analog ICs or digital logic ICs. Most semiconductors won't be damaged by handling in most cases once mounted to a printed circuit board, but that's probably not true of power FETs as may be found in the transmitter on a LoRa board, yet I see a lot of videos of people handling these little boards with little care and no ESD safe handling procedures. It probably isn't an issue with these little boards that only output around 100 mW, but it might be.

Polarization matters a lot. You have to position the antennas of both emitter and receiver in the same polarization (typically vertical since the radiation pattern is a slightly flattened donut shape)

A dipole is in the category of omni antennas, meaning non directional antennas. They radiate in a slightly flattened sphere , therefore the 2dB. You can of course increase the range with very directional antenna but at the cost of only working in a certain narrow direction. Which to use depends on your use case and needs.

​@PoweredMeshtasticEurope you could stack dipoles in a collinear fashion to achieve more "flattening" of the doughnut at the cost of sensitively to orientation, this is probably worthwhile for the base unit and is how many high gain comercial antenna for the band are assembled if you peak inside just a bunch of dipoles goin up, one can roughly guess the gain by eyeing length if they know the band and rough math.

A central forum for this Meshtastic project is the discourse forum. (Search meshtastic discourse in google)

the size (length) of the radiating elements (in this case, the two soldered copper pieces) is indeed governed by the frequency (wavelength). The size (length) of the coaxial also has an impact. Ideally it should be the length of the wavelength.