Hello,

one of my big concerns with sensors is to have something good looking without my wife asking me what this ugly plastic box is. After failed searches for good looking and small enclosures, I decided to search for electronic items and only keep their boxes. I have tried with a tiny 333cm 2$ mp3 player and managed to fit a jmodule and sensors + cr2032 inside. But the plastic is still looking too cheap.
Then I discovered those great looking wireless chargers and bought 2 different models, they are pretty bad at charging but they look really good. Only problem: they are flat. No way to put a jmodule inside so I went for an EasyPCB and removed the plastic stripes on the headers to make the pcb as flat as possible. I choosed the smaller (but thicker) black one as in the other the PCB + NRF24 was already too thick (because of the crystal).
https://www.aliexpress.com/item/QI-Wireless-Charger-Charging-Pad-for-Samsung-Galaxy-S7-S6-edge-Note-5-Nokia-HTC-8X/32694769031.html
https://www.aliexpress.com/item/Factory-price-Qi-Wireless-Charger-Charging-Pad-for-LG-V10-Other-Qi-Phone-Mmar25/32639543557.html

To fit the pcb I had to remove the right part, and then cut the corners. Still, the antenna of the NRF 24 was too much so I had to cut it too I put a 10cm wire instead, soldered at the beginning of the cut pcb antenna and ... it works really well !
Unfortunately I couldn't fit a CR2032 after putting the PCB, so I decided to experiment with alkaline button cells, the more convenient solution was to take tiny ones (LR41/AG3) and put them between power connectors of the PCB.
I also added a bicolor led (green / red) aligned with the led window of the charger, it blinks at each sending loop, wether data is sent or not so I know it's still running. When battery level is high it blinks green, when it gets low it will blink red color so I know it's time to check if I have spare batteries. Also, voltage drop is smaller on red led so it's brighter, green led is dim even at full battery and would be invisible with low battery.

I use a SHT21 sensor and at the moment I send every minute (if values changed) the temperature, humidity, battery level (%) and battery voltage (to have history). With the led blinking that's a lot to bear for LR41 batteries (rated between 25-30 mAh) but it's done on purpose, to see how fast they get empty.

The PCB ended up pretty atrocious as I did many trials and errors with it (and kept long pins 11,12,13,RST to program the board and have to bend them to fit inside the box) but fortunately when I close the box everything is hidden and the sensor really looks good. With the led flashing it really feels like a commercial sensor you could buy in a shop. I put the sensor not too far from the usb plug hole, but there are also a opening all around the bottom of the enclosure, so I have no visible difference in measure temperature/humidity when I open or close the box.
Next step is a dedicated PCB to have a clean board and be able to fit bigger coin cell(s).

Wow I'm typing too much Here are the pictures...

Everyone is busy reading your NRF5 thread @NeverDie

Today I (finally) finished a full working version of that old Livolo 3 buttons switch. I removed the RGB led on the central button as it's not visible, but the basic switch functionality with buttons/relays and blue/red status leds runs fine.
It's running with MYSBootloader, it's really convenient to update without having to switch of the fuse and unmount everything.

A (quick) video, touch sensibility is perfect now, I'm really happy with it !
MySensored Livolo 3 buttons Switch - v3 – 00:11
— Nicolas Cambier

I have to agree with @skywatch and a few others here, MySensors is relatively easy to start with using the documentation, you wire your pro mini & radio for gateway and sensor and you're running your first sensor in no time.
But as soon as you want to make things a bit more advanced, you face a lot of challenges that the doc on the website and suggested components make harder to solve :

• PA/LNA radio that fail, need wrapping in foil to have decent performance etc etc I'm pretty sure this is the most frequent cause of failure for MySensors network.
• examples with DHT sensors that are not convenient for battery usage => use of step up converters that create a whole set of new problems and unreliability
• PIR example with SR501 that runs at 5V so you need to alter them to run at lower voltage (3.3V) that's still not so convenient and they become unstable (triggered by radio tx/rx)

I'll make a list of suggestions to improve the docs, it will probably include writing a few more examples also, and some tutorials for a few things that are easy in fact easy to do but can seem hard from the outside like flashing bootloader on a pro mini or OTA update.

Currently I have restarted to test my NModule "shields", I will improve and/or fix them and probably convert the most useful ones to MySX Connector.

Working on clearing up the backlog of unfinished NModule shields, today I finished to test the dual touch button shield, made a script to use it as on/off button or as dual button with short press = on and long press = off, as seen below as a dual scene controller.
Scene controller with NModule dual touch button – 00:23
— Nicolas Cambier

I made a box so it can be easily customized depending on what you use it for. Unfortunately internet is too bad at the moment in Vietnam to use Fusion 360 so I made it with 123D Design which is less convenient and it's not really high-end assembly

Not related to MySensors but I also assembled a first version of a battery powered led light, it's small and cheap and I will assemble a bunch to put around my home when there are some power cuts in evening/night. I'm using 3020 leds and they emit a lot of light for their small size, even with low current so I expect to get around 2 hours of battery life with the cheap aliexpress 16340 batteries, and way more than needed with the 18650 cells salvaged from my old laptop battery.
My first board with a li-ion charger and it is working well, now I'm waiting for the battery protection ics (cheap DW01 from AliExpress) to arrive as my batteries are not protected.

@dbemowsk said in What did you build today (Pictures) ?:

The nice thing about owning a 3D printer is that I don't have to buy enclosures any more. I just have to buy rolls of plastic. The sky is the limit when you have a 3D printer. I do like that enclosure though.

Can't agree more, made a quick box for the lights with "crystal" PLA. You need a lot of imagination to believe it's crystal, but it's nice for a light enclosure as it acts as diffuser.

Today, a 5uA always on display with a PCF8553 LCD driver and a GDC1038 LCD from GoodDisplay. Power consumption varies with voltage but mostly with what segments are on/off, but at 3.3V with segments on to display data on all parts of display (2*4 digit numbers and 3 letters) it's always below 6uA.

Not sure why the Youtube video won't integrate as it should, but here it is for a more animated version:
Arduino ultra low power LCD (5uA) – 00:21
— NicolasVietnam

Today I finished to fix failed soldering (too old solder paste made a mess ) on the "motherboard" of my air quality sensor.
It's based on ESP32, uses a charging IC with power path so it can run on batteries for around a day or stay plugged without destroying the battery, step down from USB/battery to get VCC, storage on I2C EEPROM, flash and/or µSD card (depending on use case), one SK6812 mini RGB led as indicator, a small 240*240 IPS LCD (backlight driven directly by ESP32 pin in high drive capability mode), a 3 way switch for basic user interface + footprint for PAJ7620 gesture recognition module, accelerometer and I2C IO expander to manage the 3 way switch and interrupts from sensor modules.
Sensor modules will be added on top, connected using an FPC connector. At the moment I made only one sensor PCB able to manage usual PM, CO2 and formaldehyde sensors. Only one sensor per sensor board where an attiny841 manages the UART sensor and convert it to I2C, it also manages the 5V step up to power the sensor.
On the main board I also added an NRF24 footprint so with the same PCB I will be able to make a gateway with integrated battery backup.

I'm pretty happy with the relatively well aligned components (no, I don't have OCD ) , too bad I had to unsolder, clean and re-solder each component as it now looks botched up. But at least everything (except a missing connection on µSD card, hence the blue wire) is working,

LCD test showing jpgs from SD card

@EddyG said:

Any news on the new board? I am really interested.

I'm testing a first version right now
It's running fine but there are some annoying defaults.
I'm making improvements to the PCB now and I will publish on openhardware.io in the coming weeks.

I'm using SMD NRF 24 with antenna outside for better reception. Radio capacitor is SMD also but big size (1206) so easy to solder.

This is what the assembled board will look like, it takes a bit more surface than jModule but as you can see it's really flat, around 7mm and less than 6mm if you remove the big reset button on the pro mini.

Hello @mntlvr,

yes it has been use, see for example here :

https://forum.mysensors.org/topic/10327/rf-nano-nano-nrf24-for-just-3-50-on-aliexpress

@idanronen this is a UART to BT module, and from what I understand in the documentation the CP2102 is only here to give you access to the serial port of the module, but not to program it ?

To program it you will have to use the SWDIO/SWDCLK pins I suppose, and I'm interested to know if it can be reprogrammed because that would make a tiny NRF52832 module for boards that don't require many IOs.

@matheus-galvao said in Best options for a low current display for a battery operated node?:

GYTN-2490

Hello, I didn't do much for this one, I just used an existing PCF8576 arduino library. Are you using this exact same LCD driver, or another one ? They are not very difficult to make libraries for, I made a library for PCA9553 (much lower power) and it was easy, the annoying part is sometimes to convert the digits to "raw" data sent to the LCD driver when LCD driver designers and lcd manufacturer didn't have the same idea for segment mapping

@helmuteke said in Unkown Touch switch PCB : How to make them push instead Toggle:

ATMHK218

From google this looks like a serial eeprom.
For the other chip if it has no writing then it's impossible to help, especially when the picture is in such low resolution.

My guess is the HTTM sensors have no resistance soldered so there is no way to change it unless you remove them, add the resistance and put them back...

@zmatokan said in NModule:

@Nca78 Are you still working on this pcbs? i think it would be great to add a version that supports HiLink 220ac->5dc module on powerboard.

No I'm not working on NModules anymore, I have a few old nodes using atmega/nrf24 but I switched to NRF5 for "basic" nodes now, and to ESP32 for more "advanced" stuff.
NModule was designed for beginner and simple/riskless use, so I don't think adding high voltage option is a great idea, it's better to use an external power supply and connect the output to the powerboard.

@zmatokan said in NModule:

@Nca78 Thanks man! I managed to make it work. Seems like the problem was with radio modules. Now it works fine!

Happy to hear that, thank you for the feedback !

@NeverDie said in Coronavirus (way, way, off topic):

I'm just amazed that by now such basic, practical questions like this, which it should be fairly easy for science to answer, haven't been pinned down with certainty. Or, maybe it has, and we just need to find it somewhere in the scientific literature, unfiltered and undistorted by mass media?

The only things they can detect are some specific DNA sequences that are specific to the virus. So the tests can either find those DNA sequences, or not. There are probably ways to check if there are indeed viable viruses in the samples taken, but it must be a very hard task and not worth the energy.
For survival time of the virus I guess the most practical approach is to put live virus on different surfaces and check after x hours/days if the viruses are still "alive" and able to contaminate people, like the studies you quote earlier. Based on these studies, it doesn't seem credible that the traces found are still dangerous after 17 days.

@skywatch said in Coronavirus (way, way, off topic):

See the full article here.....
https://www.scmp.com/news/china/science/article/3080771/coronavirus-mutations-affect-deadliness-strains-chinese-study

I would take this with a grain of salt, because of this: "The authors say their findings - based on just 11 patients - are the first to show the mutation could affect the severity of illness."

You can't pretend to trace mutation and link them to different regions of the world with only 11 patients...

They claim the strain in Europe is more deadly, but it's the one that arrived in Vietnam (vast majority of the 270 cases recorded here are linked to people arriving from Europe in March) and it doesn't seem to be that deadly: most people are now cured and no none died.

Thank @skywatch that's interesting, especially the nearly 18% of asymptomatic cases, it explains why the epidemic could progress silently in many places before beeing noticed.

For the "surviving" that's not what I understand, they say "traces of SARS-CoV-2 RNA" it means they can still see it was there on some surfaces, but the virus is probably "dead". Looks more like a trace of blood that you see after a murder.

@ghiglie said in NModule:

Hi there! In these days I got some boards from my drawer - I spare quite a lot, I ordered 10 panelized one, so I have 40 NModules!
4 sensors are yet running on battery (2 on CR2032 and 2 with with 2xAA). The fifth module had an accident and I need to program it via SPI. is it safe to flash it with the antenna still soldered?

Haha that's a lot of boards. May I know what the accident was ? There was a case of a nmodule having a shortcut when manipulated, is it something similar ?
The radio SPI pins can handle 5V but not it's power supply. So as you have no regulator on radio for these boards, I see 3 choices :

1. best one = use a programmer running at 3.3V and you can power the board & radio with it. 100% safe. You can do this with the ArduinoISP sketch, a 3.3V pro mini and a ftdi adapter.
2. if you only have a 5V powered programmer, power the board separately and connect only the SPI pins with the 5V programmer. But this is out of spec as the voltage on SPI pins will be higher than VCC + 0.5V
3. open the JRDIO jumper so that the radio is not connected to VCC and use 5V programmer for SPI pins + power supply of the board. In that case to respect the datasheet of NRF24 you need to supply separately at least 3V to VCC radio, else you are in the same situation than point 2, but with the radio and that is I think a worse situation so in that case solution 2. is safer.