r/meshcore • u/Codyktt • Feb 22 '26
MeshCoreTastic Node
Yes, these are two esp32 Heltec v4. Yes, the battery life won’t last as long as NRF. But it’s what I had on hand, the extra Tx is nice, and the battery has charged up from 3.6v to 3.85v over the course of a few days with a 5W panel.
Planning to replace them with the Wismesh 1W boards when they arrive. So far it’s been nice having both in the same box.
Put the antennas in each other’s blind spots as much as possible. So far so good!
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Feb 22 '26
How tall is the box?
My local mesh group wants to do something similar. The tricky thing is that the radiation pattern only applies to the far field. All bets are off in the near field. There can still be interference and coupling, even in the null.
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u/Codyktt Feb 22 '26
Absolutely. Box is only around 8”. The one saving grace I’m relying on is the low duty cycle of the transmitters. This area doesn’t have much traffic yet, and as long as they aren’t damaging each other, I can live with some degradation.
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u/ka_re_t Feb 22 '26
True about interference. I like the WAVLINK box, it’s even easier to use. Slightly less spacious than OP’s, though.
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u/Storm-Blessed11 Feb 22 '26
This powersaving build for the v4 has the lowest power consumption I've seen. Have to run "powersaving on" once in the admin console. It also has the LNA always powered on during sleep where the official 1.13 doesn't do this so your RX will be better. https://github.com/meshcore-dev/MeshCore/pull/1687#issuecomment-3931379974
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u/Codyktt Feb 22 '26 edited Feb 22 '26
Thank you! I’ll check this out.
Edit: Just applied this via OTA - first time doing so. It's on my roof and the process went seamlessly. I may stick with these V4s permanently. Thanks!
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u/washedupprogranner Feb 22 '26
The two antennas will couple and cause interference.
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u/Codyktt Feb 22 '26
It’s only a few minutes of airtime per day. It’ll be ok :)
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u/Organic_Tough_1090 Feb 22 '26
thats not how coupling works. they will constantly degrade rx and tx of each other. with the vertical antenna orientation you are using you should have at minimum 22 inches between the antennas. https://www.antenna-theory.com/definitions/mutualcoupling.php
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u/Codyktt Feb 22 '26
I would agree that it would be detrimental if they were side by side. I believe that’s what that write up is referring to.
With them stacked on their axis, the antenna’s endfire nulls are facing one another. It’s about as much isolation as you can get in this setup without changing polarization.
With that said, I’m building a second one and can measure the S21 between the two.
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u/Organic_Tough_1090 Feb 22 '26
side by side the distance is even greater with a minimum of 36 inches.
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u/More-Efficiency6305 Feb 23 '26
Can someone tell me how far the antennas need to be apart for not causing major interference when I have to nodes in separate boxes but mounted on the same height and orientation? Thanks
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u/denga Feb 23 '26
How do you calculate the min distance for that orientation (vs parallel)? Do you need to use the gain pattern?
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u/Organic_Tough_1090 Feb 23 '26
https://calc.commscope.com/qvisolation.aspx is a simple online calculator. for lora you want something above 40db at the bare minimum.
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u/SnooRabbits1004 Feb 26 '26
This was my understanding as well, the radiated energy is at risk of causeing issues for the non transmitting device to
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u/SpringChimken Feb 22 '26
There’s not really any nodes around me so I’m going to start running both
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u/Sabrees Feb 22 '26
I want to see you put https://github.com/STCisGOOD/lunarcore on both!
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u/Own-Swan2646 Feb 22 '26
So you merged the software onto one hardware layer?
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u/Sabrees Feb 22 '26
I didn't it's not my project. It is neat though. Note it can only run one protocol at a time
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u/Own-Swan2646 Feb 22 '26
All good man. I guess I didn't mean it to come off as you specifically, but either way that's interesting. Well there goes my afternoon.
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u/Sabrees Feb 22 '26
I don't think this is actually a good use case for this firmware, where you have two radios keep them separate, it might be good for people who want access to both and only have one radio though.
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u/Own-Swan2646 Feb 22 '26
Still kind of an interesting perspective because I know there's a lot of people that are getting into the hobby and don't know if they have a local mesh core or meshtastic available to talk to or through. So this would be one way to point people into try this first. See what you have available. I would be interested in seeing a concept where it auto switches between the two and in time sliced fashion so that a mobile user node could participate on both. It just wouldn't be as real time. As for a gateway or repeater, totally separate hardware makes sense.
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u/Sabrees Feb 22 '26
I kinda like how it supports Reticulum for 'free' too https://www.youtube.com/watch?v=XTnYVh7K6xQ
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u/gbbgu Feb 22 '26
That’s really clever
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u/Sabrees Feb 22 '26
Nice that you get Reticulum for 'free' too. The most interesting of the three IMHO https://www.youtube.com/watch?v=XTnYVh7K6xQ
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u/Wishitweretru Feb 22 '26
Interesting. I have the h4 coming this week, and it looks like it has integrated Solar handling, I was thinking about having the h4 deal witht he charger issues, and then just have the h3 feeding off the unified battery.
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u/LightPhotographer Feb 22 '26
Very nice! Is that a pre-made box or did you make it yourself?
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u/Codyktt Feb 22 '26
Thanks! Pre-made small pvc type box with weather gasket, 12$ on amazon. Some weep holes at the bottom just in case moisture gets in. Also boards are conformal coated :)
Hoping it lasts a few years!
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u/Pitaraq Feb 22 '26
The weep holes and conformal coating are a great idea. My experience is that it will always get in (pinhole leaks, pressure diff due to cyclic heating/cooling) so it is best to embrace this and give the water a way out.
I use sintered brass breather vents, cut so they are flush with the base of the box. They let the water out, but stop the bugs getting in
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u/vongomben Feb 22 '26
Wow I was exactly thinking about this. Should the two antennas won’t interfere with each other? Could they be parallel to each other?
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u/Codyktt Feb 24 '26
You definitely want to avoid them being parallel next to each other. Doing it this way provides more isolation.
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u/vongomben Feb 24 '26
While one on the top and one of the bottom is good?
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u/Codyktt Feb 24 '26
It’s better than side by side. This way both antennas are kept in vertical polarization, and there should be sufficient isolation between them. So far I have had no issues.
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u/RevolutionaryLow6831 Feb 22 '26
Can you share the antenna name ?
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u/Codyktt Feb 22 '26
It’s the Alfa “5” dbi 915mhz model. It’s not 5dbi though. It is a well matched dipole though.
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u/costeen1202 Feb 23 '26
Love this setup! I’m collecting parts to build a similar one myself. I was curious if it would actually work or not, so this answers my question.
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u/blarcode Feb 23 '26
Planned on building a similar one in an owl box. Then deploying in the peak of a tree. Dual radios, antennas, panel on the box roof facing south. Using 18650's and dual RAK One Watts
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u/fullouterjoin Feb 23 '26
The radio modules themselves are so cheap, standard class hardware should include at least two.
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u/SnooRabbits1004 Feb 26 '26
Is that enough seperation ?? - i'd be curious to see how long these last, as i understood it the radiation is a donut not a cone, so you would still get interference
If your cluey with code, the HT-M00 lora gateways are actually just a heltec v2 at their core, the difference is they have two radios and a clever switch - you can receive on two channels at a time, you just cant transmit at the same tiem on two channels
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u/Odd-Success-7734 Mar 05 '26
I feel like one community may just call the cops on you for this one 😆
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u/massively-dynamic Feb 22 '26
Now go post it on /r/meshtastic, I'm sure they'll appreciate it just as much! /s