💬 Easy/Newbie PCB for MySensors

[sundberg84]

Well it looks like your battery goes to some sort of regulator before the Easy board? If so my guess is that that board is providing 2.7 v regardless of battery voltage? Have a look at @gohan and his posts about solar power and different batteries. EasyPCB is designed for 2xAA and it will not work with other voltages out of the box. The voltage divider is also dimensioned for 3.3v max and will not work with higher voltages. Again @gohan has made some experiments with this. Check his posts out. If you re-dimension the voltage divider it will work with your higher voltage.

[gohan]

@hiddenuser I don't know why you have a booster in place (unless it is a buck boost) and you need to change the voltage divider resistors if you want to read higher voltages (look at my solar project). In addition I'd put in place a LDO regulator if you want to use a lipo battery since a normal voltage regulator would require a higher Vin than a lipo battery can provide.

[hiddenuser]

@gohan said in 💬 Easy/Newbie PCB for MySensors:

Thanks @gohan for the feedback. Can I have the link to your solar project!

[gohan]

@hiddenuser look in the my project section (I'm on mobile now)

[Barna]

Hi Sundberg,

I have read there could be some problem about radio connection if the temperature is ~0C or minus, I have met this issue so I will replace the existing 4.7µ capacitor with a bigger, e.g. ~20µ.
The battery measurement contains a 0.1 uF capacitor, What do you think I do have to replace it with an another bigger one ?
thanks

Barna

[sundberg84]

@barna - i don't know to be honest. As I wrote I had issues last winter but never with that 0.1 cap. I'm running second winter now (have been as low as -8C so far) without issues.

[dbemowsk]

@barna check out this thread:
https://forum.mysensors.org/topic/186/new-library-to-read-arduino-vcc-supply-level-without-resistors-for-battery-powered-sensor-nodes-that-do-not-use-a-voltage-regulator-but-connect-directly-to-the-batteries
It is a way to monitor battery voltage without the need for the 0.1 uf capacitor and resistor setup on the board.

[Nca78]

@barna said in 💬 Easy/Newbie PCB for MySensors:

Hi Sundberg,

I have read there could be some problem about radio connection if the temperature is ~0C or minus, I have met this issue so I will replace the existing 4.7µ capacitor with a bigger, e.g. ~20µ.
The battery measurement contains a 0.1 uF capacitor, What do you think I do have to replace it with an another bigger one ?
thanks

Barna

I don't think you need, it's made to stabilize the measured voltage, in the worst case the measured voltage will be a little bit unstable but your node will still run fine.

[markjgabb]

on the subject of batteries i have to say im really impressed with the setup of these boards....
ive got a DHT and lux resistor measuring every 10 minutes, and i cant even remember how long ago i last changed the batteries...i think its about 3-4 months now....nothing special, just aldi batteries (australian cheap shopping chain)

last check they are still 65%

[dbemowsk]

@markjgabb Don't know if it's the same chain, but we have aldi stores here in the US.

[marvin78]

@dbemowsk It is. It's a german chain though ;)

[dbemowsk]

@marvin78 Never knew that.

[akamap]

Hi everybody. Finally got my newb pcb and I soldered everything needed for the pro mini 3.3v. But I ran into problems.

I think it's the cheap chinese pdo mini but I want to ask you guys. Problem id that my node doesn't work. But when I debug my node I plug my pro mini in my computer's usb and then it works.

What I could see is that when it is battery operated I can read a 3.3v value on the vcc pin of the pro mini. When I also connect via usb this value is about 3.5v.

Could it be that my pro mini requires 3.5v.
I did solder the capacitor for the radio and i'm using a 3.3v step up converter also.

Thank you

[dbemowsk]

@akamap an you post a picture of your board setup?

[gohan]

@akamap without knowing how you are powering the node, it is difficult to say.

[sundberg84]

@akamap - listen to the guys above, let us know with pictures :) Its the best.
Did you by any chance miss to solder to jumpers?
The best approach is to measure with a multimeter... put the black to GND and measure your way through the circuit from batteries, booster, jumper, pro mini and radio with the red put on each components VCC (or Vout on booster). Then you know where it goes wrong. Try to follow the schematics or the traces in the pcb to figure out how the current flows.

[dbemowsk]

@sundberg84 That's why I wanted him to send pictures. There are a number of variables that need to be in place depending on the configuration that you are using with this board. Is he using a 3.3 or 5 volt arduino, does he have a regulator, are the correct jumpers in place. Any one of these missing factors can make it not work.

[akamap]

EDIT : Seeing the pictures this big, I think I know why and it is my fault. I tried to save energy by desoldering the led on the arduino. I followed a post here on mysensors.org. But I just realized I might have desoldered the wrong thing on this arduino. I'm not sure what I desoldered, but it might be what is causing the problems (I desoldered the tiny thing below the led) I'll put a fresh one to see if this is working.

Thanks

Original response :

Ok, thank for all the answers and here is more information.

I power it via 2AA battery. I did put a jumper on the battery point. And I am using a pro mini 3.3v (Cheap chinese clone). I am using a step up regulator to step it up to 3.3v for the arduino.

I measured the voltages and they are as follow :

Without USB programmer (Not working) :
Battery : 3.00V
Input step up : 3.00V
Output Step UP : 3.35V
VCC and GND on arduino : 3.34V
VCC and GND on Radio : 3.01V

With the USB programmer pluggued in (Working) :
Battery : 3.00V
Input step up : 3.00V
Output Step UP : 3.47V
VCC and GND on arduino : 3.48V
VCC and GND on Radio : 3.00V

Another information, I did not solder directly the arduino pro mini (you will see on the pictures). I don't know what the are called but I'll call them "extender". I use them so I can unplug the arduino in case I fried the pro mini.

Here are some pictures with and without the usb programmer plugged in :

[sundberg84]

@akamap thats just the resistor... should not be the problem.
I cant see anything obvious. I have some radios without silkscreen and they work....... like a clone. Not the best but most work ok. Try adding a capacitor on the booster - might be a noisy one... I would recommend to try a 0,1uF ceramic if you have. Otherwise just wack in what you have... not to big i think.

If you power it from the booster/bat you cant power it the same time from USB! Disconnect VCC from the ftdi adapter.
Connet RX/TX and GND to begin with. RST if you need to upload. Two power sources makes one to much.

[gohan]

@akamap remember also the cap on the battery measurement side if you want to get good readings. If you want to use batteries you need to remove the voltage regulator from the pro mini, once you done your troubleshooting