After a really long time I received the boards. I finished the assembly for one and uploaded some code to it. So far it seems to work but I need to perform some more tests. I attached some pictures of the finished product. .

The silkscreen text is a little bit blurry and it was a little bit too small for the fab to print it so in some places is not right...anyways this is not important but the functionality is.
One note: the board round edges may be a little bit off the limits but that can be corrected by using some abrasive paper to remove the excess material(which I did in the above pictures and then the board fitted perfectly).

@Nca78

Elecrow is a good fab imho and yes they are very generous - I received too my boards today and instead of 5pcs I received 11pcs !!!. And this is not the first time they deliver more than requested. The price - 5$ for boards and 3.5$ shipping(standard mail) - 8.5$ in total. And yes they are the cheapest and pretty good quality pcbs - I'm very pleased about their services so far. They beat all the Chinese fabs including shipping so far(and the quality is pretty good - at least for what I need my pcbs for it's well beyond my expectations).

@NeverDie

Thanks. Well because it was cheaper/smaller than all of the Aliexpress modules found so far and it's shielded also(talking about the PTR5518 module here). So I found it to be perfect for this solution when this project was created(almost 2 months ago). Other than that nrf51 even if it's older or not so powerful than its nrf52 counterpart I found it to be more "mature" when it comes to the software part - just like atmega328p is for the Arduino world. If I remember well it was among the first one supported in sandeepmistry's nrf5 core: https://github.com/sandeepmistry/arduino-nRF5 or any other Arduino core for the nrf5xx modules so I assume its software support should be more richer than nrf52xxx.

@toyman

You can find it in my kicad repo: symbol and footprint

I didn't used it in any design so please double check.

@NeverDie

For me, elecrow is the best. But you can query this online tool which is very good: https://pcbshopper.com

OK...another remake for the classic Livolo 2 channels 1 Way EU switch and THE LAST ONE that I will make(well except for the 1 channel one which I need to work on it after this one) - @shabba I know that you waited for this. This is just the other Livolo hardware project of mine "ported" for the new hw revision that the Chinese manufacturer made. They made the 12V line available on the connector and moved it on the opposite side(the new connector is a 2mm pitch one and SMD - I choose to use the THT variant as it doesn't have any impact from a mechanical point of view and it's easier to solder for all of us the mortals around here).

The good news is that the power board is the same as the old one with some minor modifications(more or less):

1. the big MOSFET is in the same place but with a 45 degrees orientation
2. the power connector is a 2x7 pins one with the 12V line already supplied on one of the pins - less hacks for the board
3. the bistable relays are the same and drived by a ULN2003 IC(current buffer) in a TSSOP package

Thanks to @tonnerre33 for creating the new board outline which I borrowed from his project. The rest of the board is the same as the other one that I made with the dc-dc converter moved on the opposite side and with some rearrangements. Next I need to create the boards AGAIN using some external manufacturer(China of course) and then wait...and patience and... patience again and...wait.

And as always big thanks to the Mysensors community for their great effort and for maintaining this great project.

Oh...and for some reason the boards are not rendered correctly in the browser - I'm referring to the openhardware.io gerber viewer(both 2D and the 3D one) - maybe it has to do with the latest changes from KiCAD regarding the way the gerber are generated or maybe some bug in there? (I'm using the latest nightly version). The Linux gerbview utility displays them correctly.

@d00616

Hi,

This is a such great addition for this project. For long time I wanted something like this: a RF SOC with pretty good and usable software support and low power also(and a Cortex arch - pff..that's too much :simple_smile: ). I just wanted to congratulate you for your work and bringing this in to MySensors project - it's very neat and useful.

I tested it and it works just great so far. I would give you 100 likes on openhardware.io if it would be possible :simple_smile: . Thanks once again for your effort.

@NeverDie

For the swd connector - some simple wires soldered temporarily :simple_smile: and removed afterwards. The project doesn't support OTA - but can be added if desired as a DFU upload service - needs some extra work and research. But once the switches are flashed there's no need to reflash them as all the MySensors stuff is on the linux board node which can be reconfigured very easily through that web interface(the services behind it will restart automatically when the configuration file changes and the new settings are applied automatically also). I will prepare the required documentation about the whole system on my blog and there's a lot to write :simple_smile: .

Ok, so after posting some questions to CDSENET Aliexpress store(in regards to the E73-2G4M04S module):

1. Is the nrf52832 IC DEC1 pin decoupled with a 100nF capacitor as per Nordic datasheet recommendations?
2. Is the nrf52832 IC  DEC2 pin decoupled with a 100pF capacitor as per Nordic datasheet recommendations?
3. Are all the power pins of the nrf52832 IC decoupled as per  Nordic datasheet recommendations?
4. Are the external components already provided so that the internal DC-DC converter can be used?

I received this part of schematic:

The module that I bought is this one: CDSENET E73-2G4M04S

I hope that it helps demystify some things in regards to this module. Maybe @NeverDie can confirm this by checking his module connections as seen in the above schematic. I'm saying this because Chinese support is well..not so user friendly in my experience and I don't know if the above schematic is indeed what they used on their module or they just provided me an example schematic of how to use the NRF52832 IC in general instead.

nRF52832 2.4GHz Transceiver Wireless rf Module CDSENET E73-2G4M04S1B SMD 2.4 ghz Ble 5.0 Receiver transmitter Bluetooth Module

$3.12

@MiKa

I bought this switch(non-radio variant): https://www.aliexpress.com/item/Free-Shipping-White-Crystal-Glass-Switch-Panel-EU-Standard-VL-C702-11-Livolo-AC-110-250V/512770913.html?spm=2114.01010208.3.11.JqUULi&ws_ab_test=searchweb0_0,searchweb201602_4_10065_10068_10000009_10084_10083_10080_10082_10081_10060_10062_10056_10055_10037_10054_10033_10059_10032_10099_10078_10079_10077_10000012_10103_10073_10102_10000015_10096_10052_10053_10107_10050_10106_10051-10050,searchweb201603_9,afswitch_5,single_sort_0_total_tranpro_desc&btsid=518f103c-2c52-4311-9b72-2375b87824c5

The power/relays board looks like this:

Livolo EU Standard 2 Gang 1 Way Wall Touch Light Switch,Wall power sensor switch,7colors Crystal Glass Panel,with led backlight

$15.99

@skywatch

OMG...

@berkseo

Yes, it's available here. The documentation is a little bit scarce I admit but if you understand Apache MyNewt and its build system it should be pretty straightforward theoretically.

I will add more details when I have the time. The code was tested and it's in production. Works without a glitch so far.

@scalz
Thanks.

To answer your questions:

• Range is not that "big" if having multiple walls - if more than 1-2 walls things start to degrade but having more nodes in the mesh helps to overcome this. Also one can tune the number of retransmits as shown on my blog and having more relaying nodes will help a lot also. Of course my custom RF design is not perfect or that optimized. Add to that the ceramic antenna which is not that great...
• Power consumption is a plus also indeed as per node I get around 7mA x 3.3V ~ 24mW. Let's add to this the leds and touch capacitive sensor and make it 30mW on average but no more than that. I enabled the internal DC-DC converter of the MCU and add to that the fact that the nodes will stay more in RX mode hence the 6-7mA constant current draw.
• The boards are a little bit different but not much from a RF performance point of view (I'm still learning this part when it comes to PCB layout)
• The hatched ground plane differs around the capacitive pad(s) but that's because the PCB was designed initially using EasyEDA which offers "90 degree" hatches. Then I ported the PCB to KiCAD where I had to do a little trick with some polygons at 45 degree as it doesn't support hatched ground planes (not now at least or in the stable version).

I tested already both designs - the original one and the KiCAD conversion also and both are working as expected.

Yes it was lots of work and especially the power supply PCB design for which the main inspiration was the DER-622 application note from Power Integrations.

But I'm very happy with the overall result. I will update the blog with some real life videos of the whole system in action in the near future also. There will be more blog entries targeting this topic - that's for sure.

For those interested I started "documenting" my work and what I achieved so far on my blog (first time I'm "blogging" ).

@jeremushka

Same software can be used. The pin definitions need to be changed though.

@jeremushka

It can be used in a MySensors network if desired. In my case it will be used as part of a Bluetooth mesh network.

And the real product pictures now:

Short demo of touch functionality (will post later on the bluetooth mesh network functionality):
https://streamable.com/b52qb
https://streamable.com/dj3z7

Sorry for the solder bridge replacing the R20 inrush current limiting resistor..that's just temporary until I get the real component . And yes, the capacitor across the bulb is still needed but it's a very small one of 0.1uF/250Vac and it should fit near the light bulb on the ceiling (only one is needed if there are two light bulbs on the same circuit).

The aluminum foil wrapped around that sponge is to "extend" the capacitive sensor so that it reaches the front plate fake plastic button. The 3d printed clear plastic around it is to hold it in place and also to spread the small leds light.

Everything is custom made except for the front plastics.

As promised the final design! This is for one channel which I will use mostly in my house. The backside is 3d printed and it holds the electronics. The front panel and fake button are bought from the local store (Leroy Merlin) and I like it very much (it's part of modular switches design and it's very cheap). I could 3d print the front side plastics..but it I can't get the same look and feel - can't beat the molded plastic with a 3d printer for now ... (well you could use some resin or other stuff to fill the holes and then spray paint but still it's a lot of work and it doesn't worth imho)

Here are some pictures from the design. I will post later the pictures with the real product also.

@berkseo

50pcs/lot EE10-A1 Switching Power Supply High Frequency Transformer 220V to 5-12V Maximum Output 3W
https://a.aliexpress.com/_sOShjH

It's the same supplier that I used also and the lot seems to be fine...well at least the 2 pieces that I tested so far .

Now the latching relays. I found them on Aliexpress only and I received something else instead (which seems to happen from time to time) but luckily it works OK so far. So instead of Hongfa relays I got Massuse which seem to be equivalent.

Rest of the components can be sourced from LCSC which is a more trusty component supplier compared to various vendors from Aliexpress (which I already knew..but I didn't had other choices).

Oh and the PCB design and everything else was done using EasyEDA for obvious reasons (JLCPCB is very cheap and pretty good quality for a hobbyist, also their SMT service). I really like their ecosystem - you just create the design using their tool and order everything from there - very, very handy and cheap also as I already mentioned.

I did some final testing and everything seems to work just fine so I can say that this is the final revision. The touch sensing board including radio/mcu must not draw more than 10mA (it will work but won't be stable).

I updated the BOM and schematic with required voltages for caps where it's more important - the rest are 10V or so not that critical (the ceramic caps should be X5R or X7R).

Oh and I replaced the 22uF/25V capacitor with a tantalum type. Initially I used a ceramic one and the board started to sing . Well not quite..it was a more of a buzz because as you all know SMD multi layer caps are known to have this property.

Next step as already mentioned above is to design the enclosure which will be 3D printed with PETG. The front side will be a custom glass plate also which I'm thinking now how to make it look and fit better.

It works slow on my side because...well my free time available for this hobby is kind of limited.