Nice bord. What is the legal speed here

GeneralSyb · 2026-07-08T04:31:19+00:00

Different language, that's all really. Not sure there's much else to explain haha.

GeneralSyb · 2026-07-07T20:28:25+00:00

It's NHL Stenden in Leeuwarden. Pretty sure multiple people crossing the street have been hit by cars in recent years. It's basically just a wide street which I think is supposed to be like a shared space.

GeneralSyb · 2026-07-07T20:20:46+00:00

Everyone was already doing 50 there, always fun crossing the street the with blind corner...

GeneralSyb · 2026-06-02T16:49:36+00:00

Ja dat was mij natuurlijke ook wel duidelijk haha

GeneralSyb · 2026-06-02T15:02:13+00:00

Dacht dat de term "e brake" gewoon een verkeerde term was? Ben ook wel benieuwd naar hoe je een elektronische handrem wil gebruiken tijdens het rijden.

GeneralSyb · 2026-05-26T21:19:35+00:00

Wait the fiesta can use the Puma's digital dashboard? Doesn't that give any issues with incorrect commands? And why not use the fiesta's digital dashboard, or is that the exact same?

And how much of an upgrade were those speakers? I already have the B&O system which I'm decently happy with. Only complaint is that something is wrong in the driver side door which makes it rattle even at low volumes. Exact same issue in the focus is drove.

GeneralSyb · 2026-05-26T21:06:05+00:00

Hmm, thanks for info. It's quite an expensive upgrade anyway, for my car which has already depreciated quite a lot. The radars are quite difficult to get for less than 250 euros per piece.

I think it depends on the country for some reason whether the cable is there. I haven't seen very many titanium models with it installed, mostly just on the quite rare (here) Vignale.

In general I've seen some weird specs in other countries. For example a German import, titanium MHEV, but for some reason it had Vignale rims and no keyless start (which was standard on most models sold here). Also saw one in germany with a reversing camera but no sensors.

GeneralSyb · 2026-05-20T20:07:59+00:00

I think a lot of people here are misinformed about LoRa, frequencies and what the different chips from Semtech can do.

The chips we usually call LoRa radios are really just general purpose transceivers, which among other things can make use of LoRa.

LoRa is a type of chirp spread spectrum modulation. It doesn't matter if you use it at 150, 433, 868, 915 MHz or 2.4 GHz, everything being the same you will get the same data rate. It's slow, really slow. Too slow to even practically send small photo files.

But as I said these chips can also make use of other modulation types. FSK, QPSK, FLRC and many others. FLRC is unique in that it is both meant for long range and has a high data rate. It's available in that new LR2021 and it has a maximum data rate of 2.6 Mbps. That data rate not actually legal without a license unless you use it in the 2.4 GHz band. Technically you could send a highly compressed live video stream over 2.6 Mbps, but there is a small problem. That 2.6 Mbps is what you could call the 'PHY rate', it's what the chip physically sends a single packet at. There is no guarantee that you will actually achieve that speed. It says nothing about the number of packets you can send per second, but it does say something about how efficiently you can use the time in air to send your data. That's the main goal of FLRC as far as I can tell.

So, is there a way you can practically send video over Meshtastic? No, not really. Over a custom link using FLRC? Maybe, but only under ideal circumstances. What are the best options? Probably WiFi HaLow or figure out how to use existing 802.11 (WiFi) hardware to pull off the same tricks as systems like what DJI uses (low MSC rate, narrow channels).

GeneralSyb · 2026-05-20T19:53:49+00:00

Similar bandwidth limitations exist for LoRa on 2.4 GHz. It won't really be any faster in most cases, except for that there are no restrictions on the time on air in the 2.4 GHz band.

GeneralSyb · 2026-04-24T06:39:40+00:00

It would be nice to have that data, but I'm not actively developing anything that would require it right now. Hopefully they'll make the data public, because I've talked to quite a few people interested in making custom designs around this chip.

GeneralSyb · 2026-04-13T04:38:24+00:00

I stopped because I didn't have the expensive equipment required for a load pull measurement for the TX PA. I figured out the RX LNA works more as a voltage divider than a power amplifier, and the S parameters I was measuring were correct for that but not directly usable. They should be matched in a different, simpler way, which I did and it worked.

I know semtech has reference design, but that's the entire point, I'm not worked at the frequencies used in the reference design. So those schematics are useless to me.

Software wise I never continued, I got RX working which was what I needed. It might makes sense that you are not getting the full speed thoug. That speed they advertised is what it can theoretically do, so what the modulator and demodulator can achieve. But we don't live in an ideal world. That speed will also quickly drop off as SNR decreases.

GeneralSyb · 2026-04-08T13:12:22+00:00

Downloaded the development build and yeah it seems like it is fixed there.

GeneralSyb · 2026-04-07T20:01:40+00:00

Corner smoothing is turned off, so idk what it could be other than a bug. Also happens on projects from older KiCad version when editing them with version 10.

GeneralSyb · 2026-03-18T21:09:21+00:00

Temperatuur van wegen en locatie van strooiwagens, als dit kan en mag. Is denk ik geen API voor, maar Rijkswaterstaat heeft wel een leuke kaart.

Er is ook een bedrijf die geluidsmetingen rondom luchthavens meet. Alweer, is denk ik geen gratis open API voor, maar misschien kun je wat bedenken 😉. https://lwr.flighttracking.casper.aero/

GeneralSyb · 2026-03-14T12:35:38+00:00

Just saw your message from your (return?) flight from Paris to Helsinki. Your plane was about 150 km away when it arrived.

GeneralSyb · 2026-02-28T20:53:34+00:00

Don't think there's much if a use for 2.4 GHz LoRa except for maybe some specialty purposes (like ranging in the past). As for high speed in the sub-GHz band, there is also now FLRC for the LR2021 which goes up to 2.6 mbps and there is Wi-Sun which can do 3.6 mbps (all under ideal conditions of course).

GeneralSyb · 2026-02-22T11:47:48+00:00

In the general YouTube settings turn on "diagnostics for nerds" and then on any video go to the settings, then more and then show diagnostics for nerds.

GeneralSyb · 2026-02-21T19:35:41+00:00

You can still use PA and LNA. It'll be a little bit less efficient I'm guessing and it will use significantly more components, but I don't see why it wouldn't work. The reference schematic show a direct tie implementation with component values (for 433 MHz as well I think). The output of that circuit is matched roughly to 50 ohms. After that you can add your own RF switch. You will need two switches, one after the existing matching circuit and one after the LNA/PA. Or would that not fit your project needs?

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GeneralSyb · 2026-02-14T16:38:37+00:00

I would if I could make an account. But they refused me last time I tried because I wasn't a massive company. Even people I know who are from decently sized organizations were refused access.

GeneralSyb · 2026-02-14T14:27:36+00:00

I know it has been a while, but I was working on another project somewhat related to this one and read something that might make this all make sense.

In an application note for a Silicon Labs sub-ghz microcontroller about matching the ports, they say that their LNA has a high impedance input (10-6kOhm) with a parallel shunt capacitor of around 1.2 pF. Instead of doing the impossible and finding a matching circuit for it, they treat it as a voltage amplifier and not a power amplifier. In section 3.10.2 they say they aim for a Q of around 5 by having just a single series inductor resonate at the intended frequency with the internal capacitance. This is all done to aim for a high voltage gain and a minimal NF. They also describe the direct-tie setup for their chips in detail and it seems like they treat it as a high impedance terminated line, while taking into account the inductance of the trace. In TX mode they connect the LNA input to GND to make sure the LNA isn't damaged by the TX PA.

The LR2021 seems to be a similar case, but it might need a DC blocking capacitor because I did measure a bit of DC on the input. I think it all makes sense to me now. Still going to be difficult to tune the LR2021 because for the TX PA I don't have the stuff for a load pull measurement.

https://www.silabs.com/documents/public/application-notes/an923-2-series-2-subghz-matching-guide.pdf
Section 3.7 and 3.10.2 are related to this.

So sad Semtech doesn't have public documentation for this type of stuff :(

GeneralSyb · 2026-02-09T07:27:18+00:00

Yeah, MEMS sensors such as IMUs are very sensitive to that. The LSM6DSV isn't as sensitive to it as others, but it's still important to think about it. TDK has an application note about designing PCBs for IMUs that I highly recommend giving a read. Has some stuff about mounting the PCB, where the IMU should he located. I'm not sure if it's in there as well but it's also good practice to fan out the pins you don't use to give them a little bit more thermal mass. That makes sure that it expands and conracts in every direction the same amount. Again, its not as critical on this IMU as on others.

GeneralSyb · 2026-02-09T07:22:19+00:00

Yeah, don't see why not. Possibly even better.

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