I noticed in Jason's latest newsletter he mentioned Meshtastic devices he saw at the Dayton Hamvention. I've been playing with these things for a couple months and thought I'd share some of my learnings. None of what follows is intended to dissuade anyone from playing around or running their own experiments, they are neat toys, but (jumping to the bottom line real quick) Meshtastic is not ready for prime-time as a reliable comms mechanism in a disaster scenario in a way that APRS or even VARAC might be (my opinion).

There are alot of Youtube videos and Internet articles explaining what Meshtastic is and how to get started with it, so I'll not cover that part. I'll just cover some conclusions I've drawn.? There are many device makers, but two primary (most common) ones: Heltec and RAK WISBlock. Heltec have many models and are generally cheaper, but draw more power due to the chips used. People who want to build a solar-powered unit, for example, usually go with the RAK WISblock units as many have had success keeping them running for days/weeks in decent solar locations with just a 3K amp-hour battery as backup. The Heltec's, with the same battery, run down in 1-2 days (although you can power down several of the functions such as GPS and extend this to maybe 3-4 days, see this article for more about that: .

If you don't care about location tracking of your Meshtastic node (and I'll dare say for most home-based use this isn't needed) you can skip the GPS and save money and power. This is not like FT8 or other digital modes where an accurate time is required -- GPS is mostly not necessary unless you are actually using the Meshtastic node as a tracking device.?

As a beginner selecting a device to purchase, go to , drop down the "Select Target Device" list and make sure the device you intend to buy is on that list.? There are hundreds of other LoRa devices that will not run the Meshtastic software/firmware and are not listed there.? Flashing your new device with Meshtastic using that Flasher website is the first step once you have the device in hand. After that refer to the meshtastic.org website for configuration guidance.? The factory default config will work without tweaking to start. There are ALOT of config options, and lots of ways to make your device not work -- but you can always reflash back to "factory".?

The antenna you choose also plays a huge part, as in most radio comms. After testing a couple dozen of the stubby antennas that come with the Lora boards from Heltec and RAK, only about 10% of them actually had decent SWR (below 3:1) -- even when they physically appeared identical.? I've decided to build my own antennas for 915MHz (for USA use).

I'm skimming over a very few high points of a topic where there is alot to learn.? I'll leave most of that fun up to you. But why do I say "Meshtastic is not ready for prime-time as a reliable comms mechanism"? Because in areas where there are few Meshtastic nodes, messages do not get passed.? And in areas where there are many Meshtastic nodes, congestion occurs and messages do not get passed (examples are England and Sweden, with other European countries rapidly approaching the congestion level). There seems to be a narrow sweet spot where Meshtastic works nicely. There is also a contentious Meshtastic feature called MQTT.? This feature uses the Internet to pass messages if the radio-radio connections cannot be made. It is contentious because in practice it causes congestion if many nodes in an area use it. It is turned off by default and best practice calls for it to stay turned off. A bad actor could also use a bunch of MQTT-enabled Meshtastic nodes to disrupt communications -- there isn't any protection against this as of now.?

So, again, the above is my take on things to date. New firmware may modify some of the concerns above in the future.? The little Meshtastic nodes are fun to tinker with are are still relatively inexpensive, and there is alot of information available about it online.? There are Facebook groups as well as Discord groups to learn more. Have fun!
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Steve Johnson
K0OIL

Very helpful, Steve.? Thanks for taking time to share your experience.

Like many, I've been thinking about jumping on the bandwagon for exploration purposes, at least.? I have several Heltec ESP32/8266 wifi devices doing various yeoman duties and can attest to the fact that they're power-hungry.? Most are set up as sensors pumping out MQTT messages on the LAN.? Just yesterday, I was thinking about putting one in with a 25-watt solar panel, but doubts that the small batteries that I have in hand can float it continuously.

That's an important point about the "sweet spot".? From experience in disaster and other intense emergency response, I'll say there is a delicate window between not enough and too much communications.? That also depends where you sit in the response, too, of course.? From a technology perspective, we often just think that more is better without seeing how it performs under realistic stresses.? The cybersecurity of wireless communications is kind of a big thing right now.

It would be interesting to see some analysis of Meshtastic denial-of-service vulnerabilities.

?Dan
?N7SHM

Thank you for your thoughts Steve.? I've been interested in Meshtastic for about a year and finally bought two Heltec v3 devices off of Etsy, as well as some better antennas from "Garth" who makes a lot of the solar units and seems to be pretty well regarded on the Mesh discord.? I've also joined the local SoCal Mesh group as well, which has had some interesting experiments and is actively building out a solar repeater system.? Where I live there are several repeaters installed on the towers that house our amateur radio/telecom/county services radio systems, so there is some real good coverage.

I'm currently waiting on a case for one of the "Blackberry" style units.? I have the RAK board, keyboard, battery, and a third party GPS, now just waiting on the case which comes with an SMA connector for an external antenna.

I like it because with limited training I can give a unit to someone and have encrypted comms with them and they don't need a license.? With the "MeshBerries" (my term for the Lilygo T-Deck Blackberry looking units), you can just hand one to someone and go.? No phone sync needed.

I've gotten messages from San Diego, CA all the way up here near Malibu, CA (DM04 land), with the repeating and I've read reports of mesh units connecting over 200km away from each other in the UK.? Granted one was on a SOTA type site and the other was in a hot air balloon, but for the tiny devices they have and running less output power than a QRP rig, that's pretty impressive!

I think some of the DoS issues and flooding can be controlled with sub-channels.

The downsides: The Heltecs I have, on a full charge, lasted maybe 6 hours.? Pretty much have to keep them plugged in all day.? Second downside, not a whole lot of people locally to talk to.? Send a message and hope you get a response.? But there are plenty of nodes, so that's useful.

My use case - I have a group of prepper friends who would like to communicate over a large regional area in the event of an earthquake or other major disaster to make sure everyone is OK.? We're assuming that cell phones and tools like Signal are down (which they were during one of our more recent fires when a major fiberoptic line got severed by a dozer).? Some are hams, but not everyone wants to go that route and a General class would be needed.? These look like viable options.? I'm also trying to get them on GMRS as well as some of those repeaters may have range, though it appears the MyGMRS site does not always have accurate range calculations.

In a PACE plan, Mesh is likely to be the E with HF and GMRS as the A and C, respectively.? On the bright side, in our group each unique geographic region (we have three) has at least one General ham in it that can gather and relay information locally with VHF/UHF/GMRS

My area is 300+ nodes with a very active mesh. It’s fun. Cheap to jump into.?

k

开云体育

I have been playing with a RAK board/plugins for a few weeks.? The RAK unit is low current draw (also no display).? I charged my ion battery and after two weeks, still had a 60% charge.?

NOT many stations in my area (FM@(ER) But I have picked up about 6.? Only one has location info.? I have location, only because I entered its fixed location.

I have one beam printed on PC board. It has a good match to 915.?

I purchased a PC board dipole "listed" for 915, NOT.? VNA showed over 1.2G.? (Amazon).? IF it WAS made for 800+, it could be adjusted to 915, NOT.??

I only have one unit (now)? it sits in my attic, pointed out a window toward the SW.? I have picked up an airplane (so they say)? no, GPS...

I am looking at the RAK with case:

I am thinking about ECOM for the family...? I think HT's will be the best (all licensed), BUT if you "need" secure coms - it might work for short range (or longer with a repeater).

73, steve WB3LGC