Most reliable "best" radio
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@skywatch said in Most reliable "best" radio:
That 'antenna modification' just looks crazy to me,
And that is why it will be fun to test. I corrected my post above and made comments on testing.
[Edit: It was my bad for drawing people down this dark alley of antenna modifications. I’ve learned much from dark allies and only been beaten-up a few times. Yet, I still go there… to learn. Therefore, I will test it and reply.]
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@skywatch said in Most reliable "best" radio:
Yes it would, but positioning needs to be carefully maintained to avoid false results.
I think for a gateway it could make sense to use two nRF24L01 modules spaced a half wavelength apart. Then for reception you'd get all the benefits of antenna diversity, and for transmission to a particular node you could simply pick the module that receives the most packets out of the two from that node, which should give the better signal path. That could cut down on the sensitivity to positioning by better avoiding null zones.
@NeverDie I know what you mean, but "half a wavelength apart would have them in very close proximity with risk of interference. Better if the were 300mm+half a wavelenght apart. But can mysensors cope with 2 gateways on the same frequency? I didn't think that would be possible... Or were you thinking one gateway node with 2x RF modules? Now that would be interesting!
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@NeverDie I know what you mean, but "half a wavelength apart would have them in very close proximity with risk of interference. Better if the were 300mm+half a wavelenght apart. But can mysensors cope with 2 gateways on the same frequency? I didn't think that would be possible... Or were you thinking one gateway node with 2x RF modules? Now that would be interesting!
@skywatch said in Most reliable "best" radio:
@NeverDie I know what you mean, but "half a wavelength apart would have them in very close proximity with risk of interference. Better if the were 300mm+half a wavelenght apart. But can mysensors cope with 2 gateways on the same frequency? I didn't think that would be possible... Or were you thinking one gateway node with 2x RF modules? Now that would be interesting!
Either way, I suppose.
Anyway, I ordered the last 10 of the nRF52805's modules from a supplier at just $2.50 each. At that price I would have bought more, but that's all they had. I think that for that price it's a very convenient integrated MCU + radio package for Rx listening and very short-range communication. I look forward to seeing whether the arduino software for the nRF52x arduino library support has noticeably improved since the last time I tried the nRF52x series. I have fond memories of programming it then, and it can only have gotten better since then. Yes? Hopefully? Funny enough a $1 si24R1 will beat it on transmission oomph, but, meh, the nRF52805 wins with 1/3 the Rx current and decently low sleep current, even with built in RTC turned on and full RAM retention.
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@skywatch Will be interested in your results!
Here is my proposal for a test of antenna modifications that I will attempt:
- Keep it fun, light and fast.
- Use ESP8266's (ESP01's or ESP12's) because I've got some to burn.
- Antenna modifications only on either receive or transmit (recommendations?)
- Based on ESP-NOW protocol - my comfort zone.
- Report on RSSI and SNR.
- Pick one fixed range so I can keep this close to home and limited in scope.
- Most importantly, follow the hack of Pete B. and record
A. base case original
B. the 1.0, 0.75, 0.5, 0.25 wave length options
C. finally test the base case again.
Any suggestions on other points? I really don't want to burden/distract NeverDie's fine thread here, though I fear I have already. I've never hosted a thread and really don't want to. Perhaps I can post a spreadsheet somewhere.
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@skywatch Will be interested in your results!
Here is my proposal for a test of antenna modifications that I will attempt:
- Keep it fun, light and fast.
- Use ESP8266's (ESP01's or ESP12's) because I've got some to burn.
- Antenna modifications only on either receive or transmit (recommendations?)
- Based on ESP-NOW protocol - my comfort zone.
- Report on RSSI and SNR.
- Pick one fixed range so I can keep this close to home and limited in scope.
- Most importantly, follow the hack of Pete B. and record
A. base case original
B. the 1.0, 0.75, 0.5, 0.25 wave length options
C. finally test the base case again.
Any suggestions on other points? I really don't want to burden/distract NeverDie's fine thread here, though I fear I have already. I've never hosted a thread and really don't want to. Perhaps I can post a spreadsheet somewhere.
@Larson said in Most reliable "best" radio:
I really don't want to burden/distract NeverDie's fine thread here, though I fear I have already.
No worries. I welcome it. Literally, any content is good content as far as I'm concerned.
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@Larson said in Most reliable "best" radio:
I really don't want to burden/distract NeverDie's fine thread here, though I fear I have already.
No worries. I welcome it. Literally, any content is good content as far as I'm concerned.
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@NeverDie said in Most reliable "best" radio:
No worries. I welcome it. Literally, any content is good content as far as I'm concerned.
You remind me of my favorite teachers/professors. I was lucky to have many.
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@Larson This is kinda bluesky, but I was thinking it would be nice to have not just different radio modules to be pluggable into a test platform, but maybe even different MCU's to be similarly pluggable That way when moving from one version of the test platform to the next, you wouldn't necessarily have to desolder mcu's and other parts. I guess what I'm saying is that maybe the test platform could be either mainly or entirely a backplane that things get plugged into. Especially these days, when finding available MCU's is kinda hit or miss, and you might have to switch to a different MCU because of either price or availability. Anyhow, just putting the idea out there. I'm not at all sure what the best form of such a thing would be, but something that revolves around 2xAA batteries as the form factor makes sense to me.
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@Larson This is kinda bluesky, but I was thinking it would be nice to have not just different radio modules to be pluggable into a test platform, but maybe even different MCU's to be similarly pluggable That way when moving from one version of the test platform to the next, you wouldn't necessarily have to desolder mcu's and other parts. I guess what I'm saying is that maybe the test platform could be either mainly or entirely a backplane that things get plugged into. Especially these days, when finding available MCU's is kinda hit or miss, and you might have to switch to a different MCU because of either price or availability. Anyhow, just putting the idea out there. I'm not at all sure what the best form of such a thing would be, but something that revolves around 2xAA batteries as the form factor makes sense to me.
@NeverDie I like the idea. What other mcu's were you thinking of? My limited experience, and supply, is with Atmega328P, Atmega328PB, Attiny 85, Attiny 45, ESP01, and ESP12s. I do have an assortment of PIC chips but can't claim relevant experience as I left that Microchip avenue long ago once I met the easy ArduinoIDE. The downside to multiple mcu’s is, of course, scope creep and even more infinite variations.
Pluggable? Are you thinking of making a commitment to positions for VCC, GND, several digital pins, maybe an analog pin or two like your Barebones design? Then build PCB's to that footprint for different MCU's? That sounds interesting. Kind of like a MCU/PCB/Radio sandwich.
I've been studying your Barebones board and enjoy the versatility of the pin locations' multi-functional slots for different projects. Very clever. What brought me to this was that I'm building a radio PCB for yet another radio, the RFM69HCW; the footprint is different than your RFM69HW design. The reason why is that I have 10 HCW's on hand already. I'll share it after I verify that it works. Yesterday, 4 DRF1262's arrived so I'm about to make multiple OSH Park orders. Once they arrive, I'm ready to fab since the flux, the Chipquick, the Keystone AA connectors have all arrived. I've never soldered, or desoldered, a QFN before so I'm anxious about the scavenging of the 328 from a promini. Here we go!
I am going to have to take a break from my present intensity/study. I’ve got some eldercare things coming up that will dominate my schedule. But I’ll keep in touch.
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@NeverDie I like the idea. What other mcu's were you thinking of? My limited experience, and supply, is with Atmega328P, Atmega328PB, Attiny 85, Attiny 45, ESP01, and ESP12s. I do have an assortment of PIC chips but can't claim relevant experience as I left that Microchip avenue long ago once I met the easy ArduinoIDE. The downside to multiple mcu’s is, of course, scope creep and even more infinite variations.
Pluggable? Are you thinking of making a commitment to positions for VCC, GND, several digital pins, maybe an analog pin or two like your Barebones design? Then build PCB's to that footprint for different MCU's? That sounds interesting. Kind of like a MCU/PCB/Radio sandwich.
I've been studying your Barebones board and enjoy the versatility of the pin locations' multi-functional slots for different projects. Very clever. What brought me to this was that I'm building a radio PCB for yet another radio, the RFM69HCW; the footprint is different than your RFM69HW design. The reason why is that I have 10 HCW's on hand already. I'll share it after I verify that it works. Yesterday, 4 DRF1262's arrived so I'm about to make multiple OSH Park orders. Once they arrive, I'm ready to fab since the flux, the Chipquick, the Keystone AA connectors have all arrived. I've never soldered, or desoldered, a QFN before so I'm anxious about the scavenging of the 328 from a promini. Here we go!
I am going to have to take a break from my present intensity/study. I’ve got some eldercare things coming up that will dominate my schedule. But I’ll keep in touch.
@Larson said in Most reliable "best" radio:
What other mcu's were you thinking of?
Well, that's the thing: not really sure. But tentatively maybe the attiny3224 or the atmega4808/4809. Attiny3324 is very low priced, and presently available, and atmega4808 is more capable than the atmega328p. atmega4808 is same mcu as the atmega4809 (used in the Arduino Nano Every), but with a lower pincount (same as the atmega328p). A counter-argument is to just stick with the atmega328p, since everybody is already familiar with it, and just pay inflated prices for it if you don't already have spares. After all, for a test platform, you don't need many anyway. And scope creep is a very good point.
[Edit: I just now did a draft. It gives up compactness, because the 14 radio pins have to be run outside of the MCU module to connect with the radio module. Well, it was worth a shot I suppose. To keep it compact, It would need a way to make connections in a very compact way, maybe like the way some of the press-fit connectors on the Pebble watch work. Yet another thing to look into. ]
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@Larson said in Most reliable "best" radio:
What other mcu's were you thinking of?
Well, that's the thing: not really sure. But tentatively maybe the attiny3224 or the atmega4808/4809. Attiny3324 is very low priced, and presently available, and atmega4808 is more capable than the atmega328p. atmega4808 is same mcu as the atmega4809 (used in the Arduino Nano Every), but with a lower pincount (same as the atmega328p). A counter-argument is to just stick with the atmega328p, since everybody is already familiar with it, and just pay inflated prices for it if you don't already have spares. After all, for a test platform, you don't need many anyway. And scope creep is a very good point.
[Edit: I just now did a draft. It gives up compactness, because the 14 radio pins have to be run outside of the MCU module to connect with the radio module. Well, it was worth a shot I suppose. To keep it compact, It would need a way to make connections in a very compact way, maybe like the way some of the press-fit connectors on the Pebble watch work. Yet another thing to look into. ]
@NeverDie said in Most reliable "best" radio:
press-fit connectors
I had to look that up. https://www.connectpositronic.com/en/press-fit-connectors/
Very interesting. Way too advanced for my Flinstone ways.Just today I completed my first KiCAD PCB. It is every bit as challenging as Eagle. Though it does offer some advantages in 'clickability' (my term).
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@NeverDie said in Most reliable "best" radio:
press-fit connectors
I had to look that up. https://www.connectpositronic.com/en/press-fit-connectors/
Very interesting. Way too advanced for my Flinstone ways.Just today I completed my first KiCAD PCB. It is every bit as challenging as Eagle. Though it does offer some advantages in 'clickability' (my term).
@Larson said in Most reliable "best" radio:
I had to look that up. https://www.connectpositronic.com/en/press-fit-connectors/
EEVblog shows an example of one here at time index 6:50:
EEVblog #761 - Pebble Time Smartwatch Teardown – 32:40
— EEVblogIt looks way cool. There must exist something like that which doesn't need ribbon cable, where you can just press two boards together.
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@Larson said in Most reliable "best" radio:
I had to look that up. https://www.connectpositronic.com/en/press-fit-connectors/
EEVblog shows an example of one here at time index 6:50:
EEVblog #761 - Pebble Time Smartwatch Teardown – 32:40
— EEVblogIt looks way cool. There must exist something like that which doesn't need ribbon cable, where you can just press two boards together.
@NeverDie said in Most reliable "best" radio:
There must exist something like that which doesn't need ribbon cable, where you can just press two boards together.
Oh yea, that reminds me of a few teardowns of my own with malfunctioning displays in commercial products like temperature displays. There is some kind of foam boards that are pressed into the display contacts. I figured that they (manufacturers) were doing some complicated LCD pulsing to achieve what was needed much like the POV thing with 7-segment LED displays. Just looked: there are 20 connectors on the ribbon cable, and it was a pretty simple screen on a cheap device. I wanted to dig into it further but there were other shiny-objects that kept getting in the way.
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@NeverDie said in Most reliable "best" radio:
There must exist something like that which doesn't need ribbon cable, where you can just press two boards together.
Oh yea, that reminds me of a few teardowns of my own with malfunctioning displays in commercial products like temperature displays. There is some kind of foam boards that are pressed into the display contacts. I figured that they (manufacturers) were doing some complicated LCD pulsing to achieve what was needed much like the POV thing with 7-segment LED displays. Just looked: there are 20 connectors on the ribbon cable, and it was a pretty simple screen on a cheap device. I wanted to dig into it further but there were other shiny-objects that kept getting in the way.
@Larson said in Most reliable "best" radio:
@NeverDie said in Most reliable "best" radio:
There must exist something like that which doesn't need ribbon cable, where you can just press two boards together.
Oh yea, that reminds me of a few teardowns of my own with malfunctioning displays in commercial products like temperature displays. There is some kind of foam boards that are pressed into the display contacts. I figured that they (manufacturers) were doing some complicated LCD pulsing to achieve what was needed much like the POV thing with 7-segment LED displays. Just looked: there are 20 connectors on the ribbon cable, and it was a pretty simple screen on a cheap device. I wanted to dig into it further but there were other shiny-objects that kept getting in the way.
I think those may be called zebra connectors, if it's what I think you're referring to. I never could re-align those things. Once they're off, it seems like you need some kind of jig to realign them with enough precision. They appear to be pure electrical connectors. You need something else to provide mechanical regidity and hold everything in place.
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@Larson said in Most reliable "best" radio:
I had to look that up. https://www.connectpositronic.com/en/press-fit-connectors/
EEVblog shows an example of one here at time index 6:50:
EEVblog #761 - Pebble Time Smartwatch Teardown – 32:40
— EEVblogIt looks way cool. There must exist something like that which doesn't need ribbon cable, where you can just press two boards together.
@NeverDie said in Most reliable "best" radio:
It looks way cool.
Having a bit more time I watched the entire Dave Jones teardown. Very stunning review. I was feeling quite fancy after my KiCAD design but this 2015 video reminds me who I am. I am Fred Flinstone. only with Youtube. And happy enough with that!
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@NeverDie said in Most reliable "best" radio:
It looks way cool.
Having a bit more time I watched the entire Dave Jones teardown. Very stunning review. I was feeling quite fancy after my KiCAD design but this 2015 video reminds me who I am. I am Fred Flinstone. only with Youtube. And happy enough with that!
@Larson said in Most reliable "best" radio:
@NeverDie said in Most reliable "best" radio:
It looks way cool.
Having a bit more time I watched the entire Dave Jones teardown. Very stunning review. I was feeling quite fancy after my KiCAD design but this 2015 video reminds me who I am. I am Fred Flinstone. only with Youtube. And happy enough with that!
Why go half-way? Let's light up some Winston's while we're at it. ;-) Yabba Dabba Doo!
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@Larson said in Most reliable "best" radio:
@NeverDie said in Most reliable "best" radio:
By the way, when I checked the voltage remaining on the coincell taken from this keyfinder receive, it measures about 3mv. So, it got drained practically all the way to zero.
I've seen this when playing with 328's and 8266's. When voltages drop to the min threshold, the devices fail into a funky state drawing big current. For that reason, my current designs give out a yelp at a moderately low voltage, if there is a radio attached. Then go into deep sleep hoping that a rescue arrives. Deep discharges are really problematic for rechargeable liOn batteries. The advice is to abandon the battery because of potential changes to chemistry and the risk of fire on recharge.
What kind of device/component do you use to make the yelp sound? I've looked for tiny piezo's that could maybe do this, but they all seem to be different degrees of large. I know it should be possible to be tiny, becaue, for example, a digital wristwatch is able to make audible beeps. On the other hand, after looking at some teardowns, I guess digital watches uses piezo disks that are at least 1/2" in diameter. Hmmmm.... Is that really as small as it gets? Anyone here know? What about hearing aids? Surely they have something smaller. The smallest thing I've found so far has been this: https://owolff.com/page140.aspx?recordid140=534&output=pdf&delay=3000&margin=1cm which is 5mm in diameter. So, I guess forget mounting anything directly to the PCB board: wired discs are the way it's done apparently and then just tuck it somewhere inside the project enclosure.
@NeverDie said in Most reliable "best" radio:
I've looked for tiny piezo's that could maybe do this, but they all seem to be different degrees of large. I know it should be possible to be tiny, becaue, for example, a digital wristwatch is able to make audible beeps. On the other hand, after looking at some teardowns, I guess digital watches uses piezo disks that are at least 1/2" in diameter. Hmmmm.... Is that really as small as it gets? Anyone here know? What about hearing aids? Surely they have something smaller. The smallest thing I've found so far has been this: https://owolff.com/page140.aspx?recordid140=534&output=pdf&delay=3000&margin=1cm which is 5mm in diameter. So, I guess forget mounting anything directly to the PCB board: wired discs are the way it's done apparently and then just tuck it somewhere inside the project enclosure.
I found these recently: https://www.cuidevices.com/micro-buzzers. Digikey seems to carry them but the smallest was listed as "0 quantity in stock" (https://www.digikey.ca/en/product-highlight/c/cui/micro-buzzers). The 4mm square version was available but of course that's just my local digikey, YMMV.
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Surprise! I'm getting it the nRF24L01 modules to send and receive, even along my worst-case transmission path, though for some reason ack's aren't being received along that worst-case path. Not sure why there would be an asymetry like that. Apparently the RadioLib library didn't default to full transmission power, because when I set transmit power to 0dB (which gets amplified by the PA), I'm now getting great radio communication. And this is the 2.4Ghz band, no less. Who would have thought? I'm flabbergasted. If anyone wants to replicate, I've posted my modified RadioLib sketches to source-code tab of the openhardware.io project for the nRF24L01 adapter.
Even if I increase the datarate to 1mbps, the majority of the packets are still getting through. This may turn out to be a closer horserace than I had originally thought: it may yet require some careful measruements to separate out the winner.
[Edit: As a result, I just now ordered some of these E01-2G4M27D: https://www.aliexpress.com/item/3256801616913450.html?spm=a2g0o.order_list.0.0.24f21802jP9dtI
presently on sale for $4.34 each with free shipping, which allegedly contain TCXO's and, hopefully, should be a further step-up in performance. In fact, these may be the top-end of what's currently available on the market in the nRF24L01 series.Now the long wait for them to arrive....]
@NeverDie said in Most reliable "best" radio:
As a result, I just now ordered some of these E01-2G4M27D
Please let us know if they arrive with or without antennas. I've been eyeing them recently but haven't pulled the trigger yet.
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@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
— Electronoobsand the very first thing he talks about is long wires.
@NeverDie said in Most reliable "best" radio:
It does already have 100n (=0.1uF) across the DC power line, extremely near the inputs to the nRF24L01
Add a 10uF cap there. I found these radios are more stable with enough power to draw on during transmission.
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@NeverDie said in Most reliable "best" radio:
Makes me wonder what those two through-holes are for near the antenna?
On ESP8266's, I wondered if the PCB antenna could be cut with a dremel tool and be fitted with an equivalent whip-wire. It would be cheap enough to try. It looks to be that the NRF24's are maybe making that easier? Again, cheap enough to try.
Thanks for all the updates to https://www.openhardware.io/user/310/projects/NeverDie#view=projects I've been busy updating all the files I've collected. You have been hard at work. All the added *.png and *jpg pictures really help. The *.rar files make it really easy to get into the guts of it all. I got KiCAD downloaded and am looking at the E28 project at the moment. Learning a new CAD tool will be a climb of its own for me.
For the benefit of others: To extract the *.rar in Windows 10, I downloaded a utility program (WinZip 21-day trial). Maybe everyone already knows that. What I have learned is that getting to the KiCAD files is a three step zip-sandwich procedure:
- download and unzip the openhardware *.zip file.
- find the *.rar file and use a utility like WinZip to unwrap it.
- unzip the resulting *.zip file.
The resulting four files (*.pcb, *.prl, *.pro, and *.sch) will deliver KiCAD access as a project via the *.pro file. It took me most of the day to learn that. There is probably an easier way.
@Larson said in Most reliable "best" radio:
To extract the *.rar in Windows 10, I downloaded a utility program (WinZip 21-day trial).
7-Zip is an open-source alternative that will do the job equally as well. https://www.7-zip.org/