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 !
https://www.youtube.com/watch?v=G6yEdSyoMYw

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.
https://www.youtube.com/watch?v=064Jlx2eawI

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.

@Diego-Serrano said in Pir AS 312 with 2 rechargeable AAA battery. Boost needed?:

@franz-unix Hi, this post is very old I hope I can get an answer
I have ME2188 here but the behaviour of CE pin in extrange.
If I apply high to CE pin I get my correct 5v but if I change CE pin to low I get 4v on the output and I hope to get 0v.

Hello, this is the normal behavior for this chip. CE will enable the step up, but with CE low it acts as a bridge so you get input voltage at output.
Pretty annoying

Anyone can share your experience?

My experience was to add an MT9700 power switch before the voltage input of the ME2188. The EN pin of the power switch is connected to the same signal than the CE pin of the MT2188, driven by the microcontroller.
It works fine like this driving a Plantower PM sensor not a PIR (don't pay too much attention at the caps at output I just wanted to have different footprints available).

@Tmaster said in 2021 EU customs regulatory changes — where should I buy now?:

What sense makes pay 5€ on a arduino promini that cost 1.5€?

It makes perfect sense when the idea is to stop the flood of dirt cheap packages from China that abused the Universal Postal Union by paying extremely low terminal dues to receiving postal companies, making them lose money on each delivered parcel.

Hello @ANTaro, this is an ULN2003 stepper motor driver.

Hello @troost, I have no time to investigate your case (and without code, it would anyway be impossible), but maybe you can try my (basic) library for PM sensors here: https://github.com/Nca78/NcaPMSensorLight to see if you have a similar result with it.

@berkseo said in Best time of year to buy higher quality small project solar panels?:

@NeverDie
When to buy? Now.

https://mobile.twitter.com/UnbelievableEv1/status/1402321586246623232

Base materials of solar panels produced in Xinjiang using coal as energy source, not looking so great for the final carbon footprint

@Ivanli said in Private BLE Beacons with nRF52840:

Does it only work for Arduino nano? I have an Arduino UNO board and I don't know if I can achieve the same function.

Only on Nano BLE 33 not on classic nano which has no Bluetooth connectivity

@NeverDie said in LCDUINO:

the LCD components don't appear to be named, not even on the schematic

Looks like a typical text LCD like 1602 on the picture.

@DenisJ you can just wait for the arduino to be in sleep mode to switch from mA to uA.

Having a common plug for mA and µA range as the one you bought is the minimum, else you have to unplug/re-plug before the nodes gets out of sleep and obviously this will make measurement impossible. Unfortunately a lot of cheap multimeters have a separate plug and are useless in this scenario.

Best is to find a multimeter with more digits and that can use them all in the µA range. With 20 000 count you can go up to 20mA which is usually enough to measure power consumption for both sleeping and running node.

@NeverDie The study is only about "mild or moderate" illness, as long as there is a decent effect on severe cases, hospitalization and death, it's still worth distributing. And it is a preprint only, done on a low number of cases so it's a bit far fetched to draw some final conclusions from that.
AZ is very efficient against "old" variants and UK variant, and until now that's all we've seen arriving in Vietnam, so it's already a great progress if we can limit transmission of those variants. If people are less severely ill, it also means than in addition to limit the overload of hospitals people are less contagious (shown by all studies on this subject until now), so it will still slow down the spread of the virus, even for variants for which it can't really protect against.

And yes probably they don't want to use AZ in SA because the interaction with other vaccines is not known, so using AZ when the vast majority of cases in your country have a variant against which people will have a low protection is a loss of chances for people in the future. In their situation it's logic. But for most of the world where this variant is in minority in declared cases using AZ vaccine makes sense, it will help limit the propagation of the virus and limit the risk of seeing new variants appear.