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Most reliable "best" radio

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  • L Larson

    @skywatch said in Most reliable "best" radio:

    Do you have any links to this please?

    Sure, Here it is on Amazon. I got mine at Coastal Farm and Ranch. While I'm now using it for skunks and racoons, I initially used it on the swim platform of my old wooden boat that was a party scene for sea otters. They can really stink up the boat after a winter.

    skywatchS Offline
    skywatchS Offline
    skywatch
    wrote on last edited by
    #68

    @Larson Thanks- they are a LOT more expensive here, but cheaper versions are available - sorry for diverting the thread a little.

    1 Reply Last reply
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    • skywatchS skywatch

      @NeverDie Maybe just ripple on the DC? Did you scope it to see? Maybe try with 10n , 100n and 470uF caps across the DC power line? - Or if there is an onboard regulator on the RF module, then maybe that gets more noisey as the voltage drop across it increases?

      NeverDieN Offline
      NeverDieN Offline
      NeverDie
      Hero Member
      wrote on last edited by NeverDie
      #69

      @skywatch said in Most reliable "best" radio:

      @NeverDie Maybe just ripple on the DC? Did you scope it to see? Maybe try with 10n , 100n and 470uF caps across the DC power line? - Or if there is an onboard regulator on the RF module, then maybe that gets more noisey as the voltage drop across it increases?

      It does already have 100n (=0.1uF) across the DC power line, extremely near the inputs to the nRF24L01. I didn't check those other things though. However, given how widespread the use of the nRF24L01 is on this forum, if anyone happens to know whether powering it with voltage at the higher end of its range improves performance, please post. I think for the LoRa chips it doesn't matter, because they all down-convert anyway. Maybe the nRF24L01 does as well? I really hadn't expected the nRF24L01, boosted as it was with PA and LNA, to do as well as it did. So, there's that added layer of PA + LNA complexity that may have something to do with it, not just the nRF24L01 chip itself. If I was focused on just one particular chip or module, I could do those tests. But multiply that workload by six or so other radio modules, all with different idiosyncrasies, and I quickly run out of time. I may have bitten off more than I can chew. So, I just have to draw the line and either come back to it in the future or not, depending on how the global picture develops. But if someone already happens to know the answer, then hopefully they might make a posting.

      This guy just recently did a video on nRF24L01 problems:
      NRF24 Frustration - Radio module doesn't work? – 12:46
      — Electronoobs

      and the very first thing he talks about is long wires.

      skywatchS A 2 Replies Last reply
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      • L Larson

        @NeverDie said in Most reliable "best" radio:

        I started this radio testing with the expectation that one radio, or at least one type of radio, would stand head-and-shoulders above the rest, regardless of antenna type.

        Yep. And that is why I was thrilled with your earlier conclusions about the SX1262. Andreas Spiess convinced me that maximizing design parameters depend on the needs. Bit rate, bandwidth, power demands, range, and other factors are all working against each other, or with each other. Wish I knew the fundamentals and that is my aim. It would be fun to stay with one radio and just change the parameters and antennae. That has probably been done in academic circles. Imagine what led to the progressive development of different radios. I'm sure it wasn't random. We are left to discover why.

        Back to school for me.

        NeverDieN Offline
        NeverDieN Offline
        NeverDie
        Hero Member
        wrote on last edited by NeverDie
        #70

        @Larson said in Most reliable "best" radio:

        @NeverDie said in Most reliable "best" radio:

        I started this radio testing with the expectation that one radio, or at least one type of radio, would stand head-and-shoulders above the rest, regardless of antenna type.

        Yep. And that is why I was thrilled with your earlier conclusions about the SX1262. Andreas Spiess convinced me that maximizing design parameters depend on the needs. Bit rate, bandwidth, power demands, range, and other factors are all working against each other, or with each other. Wish I knew the fundamentals and that is my aim. It would be fun to stay with one radio and just change the parameters and antennae. That has probably been done in academic circles. Imagine what led to the progressive development of different radios. I'm sure it wasn't random. We are left to discover why.

        Back to school for me.

        I did that once with the RFM69, and the parameters on that radio are numerous and a real challenge to fully understand. The API of the newer LoRa radios is a lot simpler, which is fine by me.

        If it weren't for the 2mbps, or even 1mbps, capability of the nRF24L01 (and related nrf5x modules, of course), I would drop the nRF24L01 like a hot brick. But those high datarates, and especially mysensors support for OTA updates using it, offer a compelling advantage.

        So, now that there's a common test platform--one without long wires--we'll just see how it all develops.

        It would be fun to test the si4468, which looks very capable, but I think I'm already at the limit of what I can consider all at one time.

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        • NeverDieN Offline
          NeverDieN Offline
          NeverDie
          Hero Member
          wrote on last edited by NeverDie
          #71

          @Larson Now that you have a PPK2, there's an easy way you can check for whether or not your plain, ordinary nRF24L01 chips are fake or not: looking at the Tx and Rx current draws and comparing them to the datasheet. For instance, on this particular nRF24L01 module:
          alt text

          Here is the Tx and Rx profile from running the RadioLib transmit script I posted in source code section:
          nrf24L01_tx_rx_currents.png

          The first plateau is the transmit current. The second plateau is the Rx current, where it's listening for an ACK. Well, as you can see, the Tx current is about 26-27ma and the Rx current is around 14-15ma. So, next, compare that to the specifications in the nRF24L01 datasheet:
          nrf24L01_datasheet_currents.JPG

          and you can see that the values don't match. Not even close! 26-27ma is way beyond the spec of 11.3ma for maximum current draw,and 14-15ma is above the max of 12.3ma for Rx. So, the chip on this module, even though it says, as you can clearly see in the photo itself, that it is NRF 24L01+, it's a total fake. No question about it. Not only that, but if you want to, you can identify exactly which fake chip that it is, by looking at the datasheets of known fakes and looking for a match.

          When in doubt you can also measure and compare sleep currents, which varies between the real and various fake chips. As you'd probably expect, Nordic has the lowest sleep current of any of them, at least as far as I'm aware.

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          • NeverDieN Offline
            NeverDieN Offline
            NeverDie
            Hero Member
            wrote on last edited by NeverDie
            #72

            @Larson In this case, it's almost certainly the si24R1 chip, because if you look at the datasheet here: https://datasheet.lcsc.com/lcsc/1811142211_Nanjing-Zhongke-Microelectronics-Si24R1_C14436.pdf and zoom in on the electrical specification, you see that the specified currents are:
            si24R1_datasheet_currents.JPG

            which is a very close match.

            :smile:

            I've written about this before (here: https://forum.mysensors.org/topic/1664/which-are-the-best-nrf24l01-modules/285 , where it took me a lot of effort to finally figure all this out), but it's so buried at this point that I doubt anyone new to the game is even aware of it. So, I include it here, as bonus perk for anyone who happens to be reading this thread. Nice, ya?

            L 1 Reply Last reply
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            • NeverDieN Offline
              NeverDieN Offline
              NeverDie
              Hero Member
              wrote on last edited by NeverDie
              #73

              By the way, if I did end up using the nRF24L01 (or nRF5x series), I'd like to do what I outlined in the last post on that thread (https://forum.mysensors.org/topic/1664/which-are-the-best-nrf24l01-modules/309?_=1654977950928), which is to do channel hopping and time synchronization among motes. There are some interesting demos on distributed time synchronization which are pretty cool:
              Proportional Integral Clock Synchronization in Wireless Sensor Networks – 01:00
              — Kasım Sinan Yıldırım

              One simple (but maybe not the best technique) is to have each node transmit its local time in some kind of sequence, while the other nodes listen and take note. Then by averaging these local times over a few iterations, the group converges onto a single time. Pretty neat, huh? I would imagine that, more efficient and less complex, would be to have a powered wireless time server, and then everything syncs to that.

              L 1 Reply Last reply
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              • NeverDieN Offline
                NeverDieN Offline
                NeverDie
                Hero Member
                wrote on last edited by NeverDie
                #74

                And this youtube succinctly explains why it's worthwhile:
                Wheel of Blinking LEDs – Wireless Time Synchronization – 02:50
                — Analog Devices, Inc.

                TL;DR: much longer battery life, among other things.

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                • NeverDieN NeverDie

                  @skywatch said in Most reliable "best" radio:

                  @NeverDie Maybe just ripple on the DC? Did you scope it to see? Maybe try with 10n , 100n and 470uF caps across the DC power line? - Or if there is an onboard regulator on the RF module, then maybe that gets more noisey as the voltage drop across it increases?

                  It does already have 100n (=0.1uF) across the DC power line, extremely near the inputs to the nRF24L01. I didn't check those other things though. However, given how widespread the use of the nRF24L01 is on this forum, if anyone happens to know whether powering it with voltage at the higher end of its range improves performance, please post. I think for the LoRa chips it doesn't matter, because they all down-convert anyway. Maybe the nRF24L01 does as well? I really hadn't expected the nRF24L01, boosted as it was with PA and LNA, to do as well as it did. So, there's that added layer of PA + LNA complexity that may have something to do with it, not just the nRF24L01 chip itself. If I was focused on just one particular chip or module, I could do those tests. But multiply that workload by six or so other radio modules, all with different idiosyncrasies, and I quickly run out of time. I may have bitten off more than I can chew. So, I just have to draw the line and either come back to it in the future or not, depending on how the global picture develops. But if someone already happens to know the answer, then hopefully they might make a posting.

                  This guy just recently did a video on nRF24L01 problems:
                  NRF24 Frustration - Radio module doesn't work? – 12:46
                  — Electronoobs

                  and the very first thing he talks about is long wires.

                  skywatchS Offline
                  skywatchS Offline
                  skywatch
                  wrote on last edited by skywatch
                  #75

                  @NeverDie You probably already considered this but using a co-ax cable for the power would offer some sheilding and also after watching the video you linked maybe some of those tiny ferrite beads on the data and power at the radio might be of help.

                  I had to chuckle when the guy in the video showed how he connected an external antenna without first removing the link to the PCB one!

                  If I can I will try one of the cdebyte modules on 3.6V and see if they are still good... Remind me in a week if I don't get it done!

                  NeverDieN 1 Reply Last reply
                  1
                  • skywatchS skywatch

                    @NeverDie You probably already considered this but using a co-ax cable for the power would offer some sheilding and also after watching the video you linked maybe some of those tiny ferrite beads on the data and power at the radio might be of help.

                    I had to chuckle when the guy in the video showed how he connected an external antenna without first removing the link to the PCB one!

                    If I can I will try one of the cdebyte modules on 3.6V and see if they are still good... Remind me in a week if I don't get it done!

                    NeverDieN Offline
                    NeverDieN Offline
                    NeverDie
                    Hero Member
                    wrote on last edited by NeverDie
                    #76

                    @skywatch said in Most reliable "best" radio:

                    those tiny ferrite beads

                    Have you tried it before? Exactly which tiny ferrite beads do you recommend? Mouser lists over 4,200 different ones.

                    skywatchS 1 Reply Last reply
                    0
                    • NeverDieN Offline
                      NeverDieN Offline
                      NeverDie
                      Hero Member
                      wrote on last edited by NeverDie
                      #77

                      Well, the nRF24L01 datasheet says, "The nRF24L01 transmitter PLL operates in open loop when in TX
                      mode. It is important to never keep the nRF24L01 in TX mode for more than 4ms at a time."

                      Disappointing, but I believe I can work around that limitation.

                      Why is there a limitation on Tx time but not Rx time? Is it a thermal issue of some kind?

                      skywatchS 1 Reply Last reply
                      0
                      • NeverDieN NeverDie

                        @Larson In this case, it's almost certainly the si24R1 chip, because if you look at the datasheet here: https://datasheet.lcsc.com/lcsc/1811142211_Nanjing-Zhongke-Microelectronics-Si24R1_C14436.pdf and zoom in on the electrical specification, you see that the specified currents are:
                        si24R1_datasheet_currents.JPG

                        which is a very close match.

                        :smile:

                        I've written about this before (here: https://forum.mysensors.org/topic/1664/which-are-the-best-nrf24l01-modules/285 , where it took me a lot of effort to finally figure all this out), but it's so buried at this point that I doubt anyone new to the game is even aware of it. So, I include it here, as bonus perk for anyone who happens to be reading this thread. Nice, ya?

                        L Offline
                        L Offline
                        Larson
                        wrote on last edited by Larson
                        #78

                        @NeverDie said in Most reliable "best" radio:

                        I've written about this before (here: https://forum.mysensors.org/topic/1664/which-are-the-best-nrf24l01-modules/285 , where it took me a lot of effort to finally figure all this out), but it's so buried at this point that I doubt anyone new to the game is even aware of it. So, I include it here, as bonus perk for anyone who happens to be reading this thread. Nice, ya?

                        Yes, very nice. But how would you know where to look for the si24R1 chip amongst the others? I haven't read the other thread, just yet - it is the end of a very long sweaty fuse-setting day. Not only just a perk, your writing on these subjects is a library for others. Like today, I'm reading Nick Gammon's posts from 2012. They are there and very relevant still - I spend much of the day reading them. In 2032, should we get that far, folks will be upstudying your material.

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                        • NeverDieN Offline
                          NeverDieN Offline
                          NeverDie
                          Hero Member
                          wrote on last edited by NeverDie
                          #79

                          @Larson Somewhere I found a list of known clones. I linked to it in the original thread that I referenced above. si24R1 is China's clone of the nRF24L01. Ebyte even explicitly advertises it as a clone on their website and in their aliexpress store. A lot of times if you see an advertisement for an "enhanced power" nRF24L01 that doesn't otherwise contain a PA, it's an si24R1, because it has a 7dBm Tx power, versus a max 0dBm Tx power for the nRF24L01.

                          L 1 Reply Last reply
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                          • NeverDieN NeverDie

                            @skywatch said in Most reliable "best" radio:

                            those tiny ferrite beads

                            Have you tried it before? Exactly which tiny ferrite beads do you recommend? Mouser lists over 4,200 different ones.

                            skywatchS Offline
                            skywatchS Offline
                            skywatch
                            wrote on last edited by skywatch
                            #80

                            @NeverDie I have not tried them for this particular application, but have used them for SMPSU and the larger clamp on styles for SDR and other RF devices.

                            They used to be quite cheap so trying a size that fits snuggly over the wires you are using should help.

                            I see that guy in the video you posted twisting the ground wire with the data wires. This could simply be adding capacitance to the circuit or acting as a common mode rejection against transient interference. I wonder why he didn't try different value pull-up resistors on the data lines to see if that would help.

                            L 1 Reply Last reply
                            0
                            • NeverDieN NeverDie

                              Well, the nRF24L01 datasheet says, "The nRF24L01 transmitter PLL operates in open loop when in TX
                              mode. It is important to never keep the nRF24L01 in TX mode for more than 4ms at a time."

                              Disappointing, but I believe I can work around that limitation.

                              Why is there a limitation on Tx time but not Rx time? Is it a thermal issue of some kind?

                              skywatchS Offline
                              skywatchS Offline
                              skywatch
                              wrote on last edited by
                              #81

                              @NeverDie I suspect that in 'open loop' (i.e. no feedback as I understand that to mean) then frequency stability over a longer period might be questionable. So to be safe they recommend a limit across which frequency drift won't be noticable. But as always, I could be completely wrong!

                              NeverDieN 1 Reply Last reply
                              0
                              • skywatchS skywatch

                                @NeverDie I suspect that in 'open loop' (i.e. no feedback as I understand that to mean) then frequency stability over a longer period might be questionable. So to be safe they recommend a limit across which frequency drift won't be noticable. But as always, I could be completely wrong!

                                NeverDieN Offline
                                NeverDieN Offline
                                NeverDie
                                Hero Member
                                wrote on last edited by NeverDie
                                #82

                                @skywatch said in Most reliable "best" radio:

                                @NeverDie I suspect that in 'open loop' (i.e. no feedback as I understand that to mean) then frequency stability over a longer period might be questionable. So to be safe they recommend a limit across which frequency drift won't be noticable. But as always, I could be completely wrong!

                                That's what I was thinking also, but if that were the case, why would the 4ms limit apply only to Tx and not to Rx? I guess the only way to find out is to run it longer than recommended and see what happens. In the worst case I burn out a module, but they're so cheap it would be worth the sacrifice.

                                What's a bit weird is that it doesn't say anything beyond not keeping it on for more than 4ms. It doesn't indicate that it needs a rest period or anything, so, yeah, I'm guessing you're right: it's some kind of frequency stability thing that mysteriously applies to Tx and not to Rx for some reason.

                                skywatchS 1 Reply Last reply
                                0
                                • NeverDieN NeverDie

                                  By the way, if I did end up using the nRF24L01 (or nRF5x series), I'd like to do what I outlined in the last post on that thread (https://forum.mysensors.org/topic/1664/which-are-the-best-nrf24l01-modules/309?_=1654977950928), which is to do channel hopping and time synchronization among motes. There are some interesting demos on distributed time synchronization which are pretty cool:
                                  Proportional Integral Clock Synchronization in Wireless Sensor Networks – 01:00
                                  — Kasım Sinan Yıldırım

                                  One simple (but maybe not the best technique) is to have each node transmit its local time in some kind of sequence, while the other nodes listen and take note. Then by averaging these local times over a few iterations, the group converges onto a single time. Pretty neat, huh? I would imagine that, more efficient and less complex, would be to have a powered wireless time server, and then everything syncs to that.

                                  L Offline
                                  L Offline
                                  Larson
                                  wrote on last edited by
                                  #83

                                  @NeverDie said in Most reliable "best" radio:

                                  which is to do channel hopping and time synchronization among motes.

                                  A guy by the name DeKay played with frequence hopping when trying to hack a Davis Pro Vantage Pro Weather station. He has several blogs about this. Here is one: [http://madscientistlabs.blogspot.com/2014/02/build-your-own-davis-weather-station_17.html] but there are others. Kobuki was one of the contributors of note.

                                  1 Reply Last reply
                                  1
                                  • NeverDieN NeverDie

                                    @Larson Somewhere I found a list of known clones. I linked to it in the original thread that I referenced above. si24R1 is China's clone of the nRF24L01. Ebyte even explicitly advertises it as a clone on their website and in their aliexpress store. A lot of times if you see an advertisement for an "enhanced power" nRF24L01 that doesn't otherwise contain a PA, it's an si24R1, because it has a 7dBm Tx power, versus a max 0dBm Tx power for the nRF24L01.

                                    L Offline
                                    L Offline
                                    Larson
                                    wrote on last edited by
                                    #84

                                    @NeverDie said in Most reliable "best" radio:

                                    ...si24R1 is China's clone of the nRF24L01. Ebyte even explicitly advertises it as a clone on their website and in their aliexpress store.

                                    On reading the comments in one of the refered Electronoobs links, I saw that the si24R1 was celebrated. If the higher TX power demand is effective ... then it it would be good to look at. I do marvel at the value that is delivered from China. It makes it possible for me to explore without worrying too much about smoking a few chips... which I have done.

                                    NeverDieN 1 Reply Last reply
                                    0
                                    • skywatchS skywatch

                                      @NeverDie I have not tried them for this particular application, but have used them for SMPSU and the larger clamp on styles for SDR and other RF devices.

                                      They used to be quite cheap so trying a size that fits snuggly over the wires you are using should help.

                                      I see that guy in the video you posted twisting the ground wire with the data wires. This could simply be adding capacitance to the circuit or acting as a common mode rejection against transient interference. I wonder why he didn't try different value pull-up resistors on the data lines to see if that would help.

                                      L Offline
                                      L Offline
                                      Larson
                                      wrote on last edited by Larson
                                      #85

                                      @skywatch said in Most reliable "best" radio:

                                      I see that guy in the video you posted twisting the ground wire with the data wires. This could simply be adding capacitance to the circuit or acting as a common mode rejection against transient interference. I wonder why he didn't try different value pull-up resistors on the data lines to see if that would help.

                                      One of the comments I saw about this twisting technique referenced a radio tech from 50 years ago and it worked for them. I like your ideas. Is there a circuit for common mode rejection? It would be worth exploring. And using a test port for different pull-up resistors, better yet a variable resistor, would allow for testing. We have tools today to explore.

                                      [edit: Now that I've learned from Hartley and Bogatin to think of the return path of signals, the twisting technique looks really appealing for prototype fly-wires. Is the common mode rejection an idea for more final PCB's? Or is it more of a breadboard idea?]

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                                      • L Larson

                                        @NeverDie said in Most reliable "best" radio:

                                        ...si24R1 is China's clone of the nRF24L01. Ebyte even explicitly advertises it as a clone on their website and in their aliexpress store.

                                        On reading the comments in one of the refered Electronoobs links, I saw that the si24R1 was celebrated. If the higher TX power demand is effective ... then it it would be good to look at. I do marvel at the value that is delivered from China. It makes it possible for me to explore without worrying too much about smoking a few chips... which I have done.

                                        NeverDieN Offline
                                        NeverDieN Offline
                                        NeverDie
                                        Hero Member
                                        wrote on last edited by NeverDie
                                        #86

                                        @Larson said in Most reliable "best" radio:

                                        @NeverDie said in Most reliable "best" radio:

                                        ...si24R1 is China's clone of the nRF24L01. Ebyte even explicitly advertises it as a clone on their website and in their aliexpress store.

                                        On reading the comments in one of the refered Electronoobs links, I saw that the si24R1 was celebrated. If the higher TX power demand is effective ... then it it would be good to look at. I do marvel at the value that is delivered from China. It makes it possible for me to explore without worrying too much about smoking a few chips... which I have done.

                                        Yes, from the standpoint of having an inexpensive transmitter without a PA the si24R1 does very noticeably outperform the Nordic nRF24L01. 7dBm vs 0dBm. I like them. Just saying that it's good to know what you have. There are known to be some imcompatabilities, but I'm forgetting among which chips they arise. IIRC, it has to do with how ACK's are handled. It can be a source of frustration if you aren't aware of it, and it doesn't help that the chip labeling may lie about just exactly what they are. I'd have no complaints if the si24R1 chips were actually labeled si24R1 instead of trying to pass themselves off as nRF24L01's by labeling themselves as such (as in the photo that I posted). Sometimes they are, but more often than not they aren't.

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                                        • NeverDieN Offline
                                          NeverDieN Offline
                                          NeverDie
                                          Hero Member
                                          wrote on last edited by NeverDie
                                          #87

                                          Judging from the "power enhanced" title in this listing: https://www.amazon.com/dp/B082VLQK1M?psc=1&ref=ppx_yo2ov_dt_b_product_details
                                          I'm guessing that they are probably si24R1's, even though the chip labeling in the photo says that they're nRF24L01's. I ordered some, and with the aid of the PPK2, I'll know soon just what they are.

                                          On Aliexpress they're even cheaper, but the wait is much, much longer: https://www.aliexpress.com/item/2251801699158809.html?spm=a2g0o.cart.0.0.202b38dax6gRtv&mp=1

                                          They're so inexpensive that for short-range maybe they're good enough. I'm sure once the chip shortage is over that atmega328p's will be back to around $1 each. A $2 transceiver is pretty amazing. Like you say, the golden age.

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