Just a warning upfront - I'm an engineer, but not an RF engineer, so I do see some things, but I'm almost guaranteed to miss others.

As far as your highlighted line, it is a trace, but not a via. A via connects the trace on one plane of copper with a trace on another plane.

That trace should really be as short and direct as possible. Wrapping around the back of the module and along other signal lines is not a good idea. I see that the closest line to it is 3.3V power, so that acts basically as ground for small signal, but any power spike is bound to couple into the antenna line as well, at least some. If possible, it would be best to have ground on both sides of the antenna trace on that side of the board, as well as the whole surface on the other side of the board from it. Might also want to guard it by having vias connect the ground planes on either side of it to make kind of a 3d cage around it.

Additionally, you should try for 50 ohm trace impedance on the antenna line. However, there is no one-size-fits-all answer for the width of this line. It depends on the exact board parameters, and even to a small amount on the frequency of the signal. There are trace width impedance calculators that you can use to get this answer. https://resources.pcb.cadence.com/blog/2019-just-how-wide-should-a-pcb-50-ohm-trace-width-be

Almost guaranteed that it's correct to ground those 4 outer pins of the antenna connector. View the datasheet of the specific connector you are using to be 100% sure.

@NeverDie said in Which vector network analyzer should we buy?:

It said version 2 was due in January.

It looks to me like it's available now. After where it mentions the 2.0, there's a link where it says 'authorized dealer.'

That link goes here: https://www.tindie.com/products/hcxqsgroup/nanovna-v2/

And it says you can buy it now for a little under $60 US.

I don't know anything else about it, but I'm also considering getting one, now that I've read about it in this thread. I like the idea.

I think your numbers look good. Nice job getting the trace much shorter - that should help a bunch.

I wouldn't even bother with an Arduino/microcontroller at all for this. Just some diodes on each circuit and maybe some transistors for powering the large LED strips, or could also use tiny relays.

But I don't see where it has anything nearly complicated enough to have code running on a chip to run anything on it. @itjobhunter if this is not helpful and you need more specific details and/or a quick napkin sketch I can throw something together to show what I'm trying to say.

At least here where I am - West coast of US - they're allowed +/- 10% and still be counted as within spec. So those numbers are fine.

The thing is, they have voltage transformers with multiple contacts inside, and they will step the voltage up or down on the neighborhood feeders as necessary to account for varying voltages on the higher voltage lines. Actually, I think the switching happens going from high to medium voltage, and there aren't really that many of the switching transformers in the system. All of your local transformers for the houses wouldn't have them - that would be far too spendy. They do it on a large scale.

But as the residential power demands change over the day, they use the switchers to keep everything balanced. They could keep the voltage variance smaller, but at the cost of more frequent switching, and every switch of the contacts creates some wear, so more maintenance eventually. Every switch also creates some ripples in the rest of the system, I'm pretty sure. But those are probably pretty minor - it's a very stiff system. Also having higher resolution on the switchers would be more complicated and have more parts/windings inside every one of them. They keep the frequency very tightly regulated, but allow the voltage to float a bit. The frequency variances they have to make up for throughout the day so that over the course of a whole day there's practically no net change at all. (For the sake of clocks that literally count cycles and therefore don't need a crystal.)

Actually, allowing the voltage to vary also has another nice benefit to the system - it allows for a natural damping of disturbances. When the voltage dips a bit because of increased demand, the power used by many resistive appliances will also dip, so that can help the system in recovering as potentially more generation is brought online. I don't think something like AC that has a spinning motor helps much, as the frequency won't vary much.

Sorry if you're aware of most of this. I worked for the power company for a while, though that has been some years ago now.

I know this an old topic now, and I don't know if this would still help you @otousset, but I ended up running across this while searching for a solution, as I had the same problem. I finally found the solution at this page: https://docs.platformio.org/en/latest/platforms/ststm32.html

What it comes down to is that there are two different 'Arduino' cores with platformio, and we have to use the 'maple' one, which has the libraries in the format that the MySensors expects to see. The line:
board_build.core = maple
has to be added to the platformio.ini file in the project folder, which switches the core to be what MySensors framework needs. Then I got it to compile without complaint. (Well, but I guess I haven't actually finished my installation to be sure that it works with the gateway...)

Yes, that does look nice, and I'm going to have to think about doing something similar. Water leak can really ruin your day!

However, how can you just casually mention "home made smart speakers" without giving more detail??? That's what I want to hear about!

I was about ready to make a bunch of them using snips.ai and was even starting on 3d printing enclosures when they announced that it was being taken over and was no longer available.

I still plan to do it, but I haven't been able to make the time yet, and I haven't settled on which setup to use instead of snips. Though most likely is Project Alice, which is kind of/sort of an open source fork of snips. (With a lot less polish. We'll see how it goes.)

Yes, lower frequencies are better for going longer distances and penetrating walls, etc. I also would not try the NRF radios. 2.4GHz almost certainly won't do it.

The 433MHz RFM69 might do it, but I would be a bit surprised. I think your best shot is to try a LoRa module, so the RFM95 might do it.

If it doesn't work right away with just the boards and basic antennas, it's always possible to get better range with a good setup of directional antennas. In fact, sometimes having the right antenna is almost more important than the radio. (Not really, but it is super important.)

Sorry about all the replies, but I just remembered one more thing. I was using the current version of MySensors, but I also then switched to the development branch, just to see if it changed anything, but that also didn't do any good. (Didn't do any harm, either.)

@CrankyCoder Rhasspy is a good one to add to my list!

I've seen the name before, but I suspect I thought it was tied to something else? For some reason I've never looked deeper into it. That was a silly oversight on my part. Thanks for the clue!

Would you mind adding your experiences to the Smart Speaker topic that I started? It would be great to hear from another user direct feedback on what that system is like! (And I would like to keep from driving this topic too much off into the weeds. )

@CrankyCoder pointed me to another candidate for the speech-to-text part; Rhasspy in a post in another thread.

Funnily enough, in reading through the documentation, it states that it interoperates with Snips, and provides a link. Even though going straight to the Snips website provides nothing but a landing page, using their docs link ends up with all kinds of info. So it's still there, but hidden from a casual search.

@CrankyCoder Rhasspy is a good one to add to my list!

I've seen the name before, but I suspect I thought it was tied to something else? For some reason I've never looked deeper into it. That was a silly oversight on my part. Thanks for the clue!

Would you mind adding your experiences to the Smart Speaker topic that I started? It would be great to hear from another user direct feedback on what that system is like! (And I would like to keep from driving this topic too much off into the weeds. )

@KevinT Yes, that was my question, thanks. I didn't realize that Android had that built in - I thought the voices you hear were generated in the cloud and then the wav or mp3 was sent to the phone. (Like when using GPS to get around or whatever.) Or is it the same voices that you hear while doing that? Is it more basic?

Anyway, thanks for the answer - that's interesting.

Yeah, Alice must be able to run on pretty much any server, but I don't know how much manual effort would be required to alter settings. Maybe they even have an easy-to-use config change that will set up everything?

What I like the most is that the 'satellites' don't need much power, because all they really need to do is wakeword detection and then piping audio back and forth. Just need one with enough grunt to do all the speech to text and back. With our use patterns, that one wouldn't even get worked all that hard for the most part.

Actually, I'm really looking forward to this, because I have a Death Star 3d printed to hold all the electronics, and an addressable 60-LED lightring to go around the outside. So it will also function as a clock and timer/stopwatch with the ring.

And I'm also adding a piezo mic to act as an impact sensor, so you can use them as targets for nerf darts. I got that idea from someone who made an alarm clock that you turn off by shooting. As soon as I saw that I knew I had to add it to my speaker.

Oh, and the depression for the laser beam from the Death Star is where the speaker mounts. I have all that 3d modeled and printed, just need to do all the electronics and programming... I just need to figure out a way to make some simulated lasers and to be able to light them up. That would also work as a bit of a speaker grille to protect it. I haven't spent much time on that part, but I think it would be a nice addition, and I need to see about it...

@KevinT What is it that actually does the conversion from text to speech? Is it on the phone? Did you create that part, or did it come with the phone, or something else?

Yes, I'm aware of the keyword spotting, but I can't think of any applications in my house where that would be enough, except for using it to get the wake word for a more fully-fledged speech to text. I hadn't see the Edge Impulse learning site, though, so thanks for that!

I also hadn't even considered something like the mid-range like in the Wio Terminal link you have. I have to study that some and think about it. That could be enough for what I'm doing... But in any case I want to work through the tutorial and see what I can learn.

But overall I'm still a bit set on the full-fledged idea with Project Alice. Which might actually not be reasonable. I need to think about it. It could just be that I set myself on that a while back and now going with anything else feels like giving up? But in any case, these other options will be great learning experiences, so I'm going to look into them.

Thanks!

@KevinT yes, besides electrical issues and fires, there's not much that will destroy a house faster than water! Very important to catch it quickly!

As far as the speakers, I did start a new thread. https://forum.mysensors.org/topic/11853/smart-speakers

Well, this is not super on-topic for the site, but there's probably a lot of cross-over interest with people here on doing a local smart speaker.

It came up in another thread with @KevinT, but was really not the topic of that thread, so I'm starting this one to have a better place to hold the discussion.

So the current "smart speakers" of yours are really just output devices? Is the MQTT to speech internal to the phone, or does something else do that?

I'd definitely be interested in continuing the discussion. Kind of off topic for this whole site, since its use of MySensors would be minimal. There would be a two-way integration, but it wouldn't be very tightly coupled.

My thought was a raspberry pi, or even a powerful server if needed for the speech recognition and also for responses, and then just raspberry pi zeros for the satellite devices. (They would be doing wake word detection and then simply passing audio back and forth, so not a lot of power needed here.) It would be able to be a pretty cheap overall solution, while keeping full privacy because everything would be done here at the house, not sent out to the cloud.

I'm going to add links here to what I think are relevant projects.

https://snips.ai/ is what got me started on the idea and general architecture, but they got bought out and shut down before I could really get my whole plan off the ground. I was still fighting the learning curve and only had a single device kind-of working like I wanted when the announcement was made. Their website now is just a landing page that points to sonos, so it's useless. Used to be that you could still view the old info there for a while.

Project Alice is an open-source fork of what was snips. Snips had been mostly open-source, with the large exception of their web-configurator tool. Project Alice is not a finished product, but it looks like it's in a useable state, though it also looks like it's mostly the passion project of a single developer. I think this is the way that I'm going to go, once I get enough free time to wrap my mind around it all. https://github.com/project-alice-assistant/ProjectAlice https://community.projectalice.io/

Then there's Mycroft. https://mycroft.ai/ It looks reasonably good for a front-end, but they use Google on the speech recognition. At least they realize the privacy downside of this, and they aggregate everyone's speech snippets and proxy it through their own server, so that minimizes the amount of info that Google could get out of it. They have been supporting Mozilla's Deep Speech project, but I don't think that you can send requests to that over the cloud. Though they also say that if you have hardware with enough power to run the Mozilla service locally that you can set it to do that. https://mycroft-ai.gitbook.io/docs/using-mycroft-ai/customizations/stt-engine#default-engine

While Mycroft will run on a Raspberry Pi, it needs to be a larger, more powerful one. It can't just run on a zero. https://mycroft-ai.gitbook.io/docs/using-mycroft-ai/get-mycroft/linux#system-requirements Although, now that the Zero 2 has come out, it might be enough.

Finally, just to be complete, there was the Jasper project. https://jasperproject.github.io/ I was especially interested in this one when it came out, both because it ran on a Raspberry Pi and my son is named Jasper. I thought that would be cool. It seemed like a great start, but then it died off pretty quickly. I got the feel like it was a student project and the students then were done with school and it didn't go anywhere.

That could be totally false - I didn't follow it closely. But it's been basically abandoned for quite a few years now. I didn't understand the code well enough to just pick it up and run with it, so I never did anything other than read up on it every year or two.

So that's my list for now. If nothing else, it's nice to have this all in one place for future reference. Right now I still think I'll end up going with Project Alice, but with how long it takes me to get to these things it might be a long time before I actually get anything going. If anyone else has suggestions, or things that I've missed, I'd love to hear about them!

Yes, that does look nice, and I'm going to have to think about doing something similar. Water leak can really ruin your day!

However, how can you just casually mention "home made smart speakers" without giving more detail??? That's what I want to hear about!

I was about ready to make a bunch of them using snips.ai and was even starting on 3d printing enclosures when they announced that it was being taken over and was no longer available.

I still plan to do it, but I haven't been able to make the time yet, and I haven't settled on which setup to use instead of snips. Though most likely is Project Alice, which is kind of/sort of an open source fork of snips. (With a lot less polish. We'll see how it goes.)

@kasparsd Yes, this is a very disheartening thing to see.

I would rather not have to maintain a local version with some of the fixes that I see talked about on the forums, but since there's no movement on the code, at least from looking at github, I'm left with doing a bunch of it myself if I want to incorporate the changes.

Especially bad when the changes are in a pull request and just languishing there. It's discouraging when I want to go work on something but I need to deal with the core mysensors code before I can even get to that step.

I mean, I'll deal with it cause I still appreciate mysensors and find it a net benefit, but I can certainly understand why some people either give up on it or maybe never pick it up in the first place, seeing stuff like that.

I don't know how well it would match just what you want, but there's a framework built with MySensors that is supposed to make this kind of thing pretty easy.

Check out: https://www.mysensors.org/download/node-manager

I haven't actually used it yet, but I plan to once I get some of that type of sensor up and running in the next little bit. (So I can't personally vouch for its quality or anything, but it seems like a reasonable way to get started, and for it to be on the site it has to meet some minimal level of working well, I expect.)

@nexus1212 You're using a 3V Arduino. It looks like all the patterns are correct, but it's just not getting things right. A lot of the unprintable characters in ASCII are at the start of the table, so I'm thinking maybe you have a serial connection that is expecting 5V as the 'high' voltage and what it's actually seeing is so borderline that it's not always registering correctly.

So look if there's a setting on whatever you're using to read the serial data to set it to be 3V compatible. (Maybe a physical jumper on the board?) It's so close to getting it that I bet it's something super simple like that and your Arduino is really doing it's job pretty well.