What did you build today (Pictures) ?
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@nca78 said in What did you build today (Pictures) ?:
I made a box so it can be easily customized depending on what you use it for.
Is it a 3D printed enclosure then, or did you find some other way to make it? Looks very nice.
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@neverdie said in What did you build today (Pictures) ?:
@nca78 said in What did you build today (Pictures) ?:
I made a box so it can be easily customized depending on what you use it for.
Is it a 3D printed enclosure then, or did you find some other way to make it? Looks very nice.
3D printed. Bottom of prints can look pretty good if find the good settings and print on a glass surface.
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@nca78 I would assume that pads 1 and 2 are capacitive touch surfaces, correct? very nice design.
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@dbemowsk said in What did you build today (Pictures) ?:
@nca78 I would assume that pads 1 and 2 are capacitive touch surfaces, correct? very nice design.
Thank you !
Yes using dirt cheap TTP223 breakouts at the back so no SMD soldering needed.
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I received the next version of the leak detector PCB today. Putting it together, it checks out: thanks to a change in layout, it has the same board size as before, but now no clearance issues. i.e. No need for Kapton tape!
If I had had my own PCB CNC etcher, it would have saved me the time I lost waiting for the earlier version from the fab, only to find out that the clearances were too tight and that I would have to re-do it. Looking forward to not having such delays ever again.
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Christmas wreathe for the techie in all of us.
pretty colors
flashing
wire wrappingUses a pro mini and a lot of wire-wrapping. Other components on the circuit boards are just there for show.
(ugh, google photos links not showing up so converted to links)
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@wergeld Hadn't thought of it that way... Good call....
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Finally got the PCBs from AllPCB.com (cost 5 Euros and took a total of 7 days from order submission to free DHL delivery to Europe!!!) for my own MySensors Arduino Pro Mini prototyping board. Unfortunately the soldering iron broke during my assembly, so it's not fully finished and I couldn't test it yet, either...
This board is inspired by the Nano IO shields that are offered on AliExpress and improves it further for my needs (and switched to the Pro Mini instead of the Nano).
- Each analog and digital pin of the Pro Mini has its own VCC and GND pins,
- the board also provides its own voltage regulator, solder pins for by NRF24L01+ and RFM69H are provided (plus the 5V->3.3V XC6206 regulator),
- either a tiny 55-pin breadboard or three IĀ²C connectors can be placed on the board.
- One can also use PogoPins instead of soldering the Pro Mini (or headers for it) to burn the bootloader or change fuses on the Pro Mini via the ICSP connector.
All design files are available on GitHub: https://www.openhardware.io/view/538/Arduino-Pro-Mini-IO-Shield
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@reinhold I like how you hid the pin holes for the ICSP underneath the breadboard.
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A temperature controlled PWM fan controller for my DPS5005 power supply!
The original 2-wire fan that came with the power supply casing made an incredible amount of noise.
Using PWM to reduce its velocity made it even more noisySo, I made a fresh start and ordered a quality fan (almost as expensive as the whole casing...)
Using nothing more than a 5V pro mini, piezo speaker, DS18B20 temperature sensor and a resistor I made a full fledged fan controller
It takes the current temp from the DS18B20 (which will be mounted on the heatsink) and ramps up the fan linearly in the 30..60 C range. Below 30 C, the fan is off.
If RPM readback indicates a stalled fan, or DS18B20 returns wrong values the buzzer will force me to invest what's wrong
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@yveaux next step is to use the piezo for active noise cancelling
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@mfalkvidd don't tempt me...
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@yveaux that looks like a Noctua fan. I have a DPS5015 and I was planning to make some mods on the case (I got the other model that is bigger), so I guess I am gonna ask you for some code
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@yveaux said in What did you build today (Pictures) ?:
The original 2-wire fan that came with the power supply casing made an incredible amount of noise.
Using PWM to reduce its velocity made it even more noisyLess funny that way but did you try to lower the PWM frequency of the atmega to it's minimum ? I had the same problem with the fan I put in my fridge cabinet and low PWM frequency solved it.
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@nca78 I did fiddle with the frequency, but the fan was just total crap, so I decided to replace it anyhow.
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An RC filter could probably also make wonders for the fan. I had to add one for the parts fan on my 3D printer. Couldn't control the speed with PWM without the RC filter..
Btw. probably a bit over the top of using an arduino as fan control? Unless you plan on adding a NRF radio, and report the temperature + PWM duty cycle to your mysensors system, and store the values in influxdb?
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@tbowmo said in What did you build today (Pictures) ?:
Btw. probably a bit over the top of using an arduino as fan control?
Really? How so? Seems like the end result will be as quiet as possible, yet avoids stalling.
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@neverdie said in What did you build today (Pictures) ?:
@tbowmo said in What did you build today (Pictures) ?:
Btw. probably a bit over the top of using an arduino as fan control?
Really? How so? Seems like the end result will be as quiet as possible, yet avoids stalling.
Indeed! I thought of going the analog way, but the final solution would be more expensive, I didn't have the parts at hand, it wouldn't have as many features and it would have cost me a lot more time...
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@tbowmo said in What did you build today (Pictures) ?:
An RC filter could probably also make wonders for the fan.
Probably, but again, the fan was total crap and made a lot of wind noise due to the bad condition of its blades.
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a 555 and a couple of resistors / capacitors..
https://electronics.stackexchange.com/questions/91102/555-temperature-controlled-pwm
But then again, I recon that most of us might have more atmega328 based boards, than 555's in the parts bin
about the RC for PWM, it was meant as a hint for others that might fight problems with a fan that they couldn't control properly with PWM..
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@tbowmo 555s need knowledge... i wouldn't know what to do with these except cufflinks
arduinos are much more accessible
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@tbowmo said in What did you build today (Pictures) ?:
a 555 and a couple of resistors / capacitors..
https://electronics.stackexchange.com/questions/91102/555-temperature-controlled-pwmStill, no tacho readback to detect stalled fans, no temperature sensor verification or overtemperature warning, no initial fan spinup and little control over how the fans reacts to temperature changes....
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Testing a flow meter.It works pretty well, but at high flow rates (90 pulses per second) the esp8266 resets. Not sure if the reset is caused by too many interrupts or if the sensor uses too much power.
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Though not fully finished, I am prototyping a new in-wall switch/scene controller with an integrated 128x64 OLED display. The design is made to fit my decora wall switch design that I had posted a while back. Here is a mock up of how I think the keypad and screen will be layed out.
!
For the screen, I am hoping to display the current room temperature and possibly the outside temp. I can also scroll messages across the screen if needed. I can also do some custom graphics and icons.
I have tested the display connected to my uno with the Adafruit sample code and think it does a nice job. This is not my video, but it is the same sample code that I used to test it.
128x64 cheap OLED display Adafruit library Arduino UNO ā 00:59
ā Cutter SladeI'll post more as I get further along.
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Well as you can see, my prototyping skills are not at the level of @dbemowsk (always interested in the under side of the boards, mine look .. yeah a mess?), however I managed to create this enclosure (once closed looks nice enough).
It should control the programmable LED lights in my livingroom (900 pieces).The board is powered 5v from the same power supply as the LED's. In addition it needs to measure the lux in the livingroom to decide if it is dark enough to turn on the lights.
Initial tests looked okay, however after finding 56 effects in the Doll House of @Yveaux I decided to use that FX library as well. However the Arduino Mega is out of RAM to accomodate a full controll of the 900 LEDS. It will only control around 650 LEDS with that FX library.
After being in contact with @Yveaux we decided to use an ESP solution. I have a spare NodeMCU v3 that can house the ESP gateway sketch and will have enough memory to controll the LEDs. Well now I have to look for a nice prototyping thing/case for the NodeMCU and add a level shifter as well. The LED's control line wants to be controlled by at least 3,7v.
This is the nice thing about these kind of projects.. "There is always something to do"
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@sincze I've done and seen a lot worse than this. Good job. Any particular reason you chose to use a Arduino Mega?
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@dbemowsk Well first I started with my all time favourite... the Nano, as I have prototyping boards available.;-) but even with some simple light shows it did not have enough memory to hold de states of each individual 900 LEDs.
I moved to the Mega. as it has more memory. My sketch worked fine so I started to build the node in its box. I also looked at the Github for the Doll House inspiration. I found the library that had 56 effects. So I thought why not use that one... Migrated my sketch, did a few tests with 300 LEDS, completed the enclosure and only than found out It could not controll all the 900 leds, due to memory issue. Insufficient RAM.
But as this forum is a learning curve for me please feel free to share your thoughts. I always look at examples from others and see what I can do with it myself. I don't have fancy PCB equipment, justs a soldering iron and my own Aliexpress wearhouse with components
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@sincze I should have known. All you had to say was memory and it would have made sense, or should I say sincze. LOL. With needing to hold states of 900 LEDs, I am going to guess that they are WS2812 LED strips.
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@dbemowsk I like your buttons-OLED a lot. It would be nice to have available a generic module like this with a screen and buttons and which "just works" to use on different projects. Nice work!
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@neverdie I am hoping to soon have all of my boards posted on openhardware.io. I am just waiting for a reply on a thread I posted last night on what OHL to use when I upload them. I currently have a power supply board, the controller board that you see in the pics above, and a universal switch board that allows you to build it into everything from a single paddle switch to an 8 button scene controller. All of this fits a standard decora style US wall switch box. I designed the controller to be somewhat universal which is what gave me the flexibility for this design. I had thought about a similar design with this OLED display in which the buttons were layed out in an up, down, left, right and center select (U, D, L, R, S) configuration. If I ever get around to designing a board for this, I might see if it is possible for me to fit the buttons in a multi-configuration layout similar to my original button board where you can choose to make the 6 button layout like in my pics, or the U, D, L, R, S layout.
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@neverdie As far has having a generic module, the display and button board, or even my original button board can be used with other things. The key is just knowing the connections, and you could plug these on to any header in that configuration. Below is the layout of my controller board, but if you layed out headers in the configurations I have on this board, you could use any of my switch boards.
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Since this is still in mockup stage, this is the other button configuration I was thinking about with an up, down, left, right, and center select.
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Assembling and testing rev 5 tonight.
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So last night I got the display connected and I now have the Adafruit sample code running on it:
Wall switch OLED display test ā 01:58
ā Dan BemowskiTonight I will be installing the buttons and hopefully working on some test code for the buttons and the screen. Here is my proposal for the switch wiring. The red traces are for the columns, and the blue are for the rows.
One thing that I would like to do with this is to possibly display some animated graphics for the current weather condition. Seeing the falling stars at the end of the Adafruit test code made me think of rain or snow falling. Something like that might go outside the limits of the pro minis memory, but hey, never hurts to try.
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So I have all of the keys soldered in and wired. I did some simple tests to see how things were working. I tested with a font size of 2, and again with a font size of 4.
Font size 2.
OLED keypad test #1 ā 00:27
ā Dan BemowskiFont size 4
OLED keypad test #2 ā 00:27
ā Dan Bemowski
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Today I build a basic node for temperature (DS18B20) and analog input. Most of my nodes feature a DS18B20 connection as it only 'costs' a 4k7 resistor and a connector.
PCB is etched.
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@dbemowsk said in What did you build today (Pictures) ?:
Seeing the falling stars at the end of the Adafruit test code made me think of rain or snow falling. Something like that might go outside the limits of the pro minis memory, but hey, never hurts to try.
Hey Nice Work!
I see you are using I2C, vs SPI... that may be why your display is so much slower than the demo in the Adafruit video.
Can't wait to see the final board!
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@boozz What are those 3 pin male connectors called?
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@neverdie said in What did you build today (Pictures) ?:
@boozz What are those 3 pin male connectors called?
I guess that is molex 3 pin tht pcb connector, like this https://uk.rs-online.com/web/p/pcb-headers/4838477/
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Hi
Its been a long time since I made something Mysensors.But now I made my first WIFI node with led dimmer. Using the ESP8266 NodeMCU.
I use the VeraPlus and made a new Mysensors Device, and put in the IP of the NodeMCU.
This is not my last wifi node. I am thinking of making a motion/temp sensor next
and the box.
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one step further...
ISP works, FTDI works, test code works, and looks like a genuine board
now comes the hard part
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@andrew
What is that spring loaded contraption? Is it for holding your PCB while you solder it? If so, I can see how that would be handy.
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@neverdie said in What did you build today (Pictures) ?:
What is that spring loaded contraption? Is it for holding your PCB while you solder it? If so, I can see how that would be handy.
yes. I have a "third hand" station as well, which is good for through hole parts and pcb handling, but for smd, this could be a life saver.
this is the exact item which I ordered and which you can see on the photo:
https://www.aliexpress.com/item/8-12cm-Fixture-Motherboard-PCB-Holder-For-Mobile-Phone-Board-Repair-Tool/32767458535.html
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Today's progress on the new switch consists of finishing the basic 3D model of the wall switch plate and working on some of the programming.
For the wall plate design I do not have buttons as of yet, but the main part of the wall plate turned out good. I did the initial print in yellow because I am out of white at the moment. I am still trying to figure out the best way of printing it. In the video, you will see that the tabs are looking a bit rough. That is because I printed this one face down with supports for the tabs. If I decide to print them that way, it won't be bad because the tabs will be hidden under the wall plate cover. I will try printing them both ways to see which comes out better.
For the programming, I created a couple bitmap icons and did a sample of those icons animated on the screen. The animations toggle back and forth and each runs for about 10 seconds. One bitmap is a rain drop, and the other is a snow flake. The idea is to use these to display weather conditions. I will probably design some clouds and a sun as well and have 4 possible animated weather displays.
raindrops and snowflakes ā 00:31
ā Dan Bemowski
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Yes these are 'molex' pcb connectors.
An ebay alternative can be found at: Ebay shop cayin34
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@andrew
Where did you buy that green thing that sits on your work desk (it has some kind of ruler on it and squares). I don't know how it's called but I keep seeing it and I think I want one too. Thanks.
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@mtiutiu
here I use esd safe mate etc when I do electronics (maybe too much paranoid.. and I don't know if there are with ruler), but these green mates are nice for tinkering, sure.
if you google "cutting mate ruler" you'll find what you want
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@mtiutiu just search for "cutting mat"
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@mtiutiu I got one of those blue silicon heat resistant mats with magnets so I can use the heat gun over it
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@gohan said in What did you build today (Pictures) ?:
@mtiutiu I got one of those blue silicon heat resistant mats with magnets so I can use the heat gun over it
Do you have a link for that? Sounds very useful, especially when soldering things that might get very hot (though maybe I won't need it as much after I get the PCB holder).
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Trying to get a programmer for Sigfox/LoRaWAN devices to work for a non-MySensors project. (the programmer is from a nice Dutch company called 1M2M)
I like the Swedish-branded usb cable
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from my previous posts the PCB CNC milling came out as an interesting topic. maybe another method, working with photo resist PCBs and UV exposure, could be interesting for others. so, for those, who are interested in this, I just documented my solution (not the technique, but my tool) recently.
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@neverdie they get on sale quite often on banggood but are also available on aliexpress: usually they are on 3 sizes and the biggest has some slots with a lid and others with magnets; there are also some small slots with numbers to keep track of the screws you are disassembling and a ruler at the bottom
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@andrew nice! Read about it on hackaday today!
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@yveaux thanks I finally managed to document it, there are some other stuff in the queue as well
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@dbemowsk You are correct , well at least I thought I bought those but got: SK6812 RGBW (comparable to ws2812b). The pretty work just fine.
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Some more sample display layouts.
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Reverse-engineering a bluetooth battery monitor from Conrad.The battery monitor has an Android and iOS app that displays voltage, but I wanted to read the data from an ESP32 (lower right corner of the pic).
This hack is probably worth a thread on its own, will add that later.
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More info on my ble hack: https://forum.mysensors.org/topic/8773/reverse-engineering-a-gl10-ble-bluetooth-battery-monitor-using-esp32
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Maybe a bit off-topic, but I use octoprint as server for my 3d printer, and use Domoticz as homeautomation server. I want to know when 3D print is done, so I created a node-red flow that connects this via MQTT, so domotics shows print progress...
https://www.domoticz.com/forum/viewtopic.php?f=21&t=14021&p=162935#p162935
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@bjacobse I literally just started using octoprint about a week ago. I am curious how you get the progress data into node-red to send over MQTT?
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Well.. I didn't build it as it was already assembled, but I did had to some soldering to put it together and also did a mod to the case by adding 2 extra binding posts to the front. Btw it is a DPS5015 with a BT module that I fitted behind the screen
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@dbemowsk
hi did you check the link I supplied? I rather discuss the topic in domoticz forum, as it could benefit other Domoticz/octoprint userrs
https://www.domoticz.com/forum/viewtopic.php?f=21&t=14021&p=162935#p162935
but I have installed on the octoprint the mqtt plugin, as my domoticz is also running both mosquitto and node-red, I specify the ip adress for domoticz in setup the broker in octoprint plugin mqtt,
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Finalised my indoor weather station with light intensity measurement build around a WeMos D1 mini. The system is using a BME280 module for pressure, humidity and temperature measurement. The light intensity is using a normal plain good old LDR.
Step down converter to convert input voltage towards 5 Volt.
Of course using the esp8266 MySensors solution! Great achievement to all involved in building it. Really awesome!Case designed in Onshape and printed on a Ultimaker 2+.
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@arnold the print quality of that box looks amazing
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@gohan Thank you! Although I have some warping on one of the corners unfortunately.
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@arnold So that is a 3D printed case? Curious where you got the knurled screw inserts that you used in the case for the cover? I am a computer tech and deal with a lot of E-waste disposal and on occasion have grabbed some similar ones from old laptop case parts, but those are really small. The ones that you have there are a decent size.
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@dbemowsk ], yes it's a fully printed case using PLA material.
I bought some nice and decent brass knurled from Banggood. Bought directly some M3 bolts made of stainless steel also at Banggood.The bolts you can get in different lengths.
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@arnold said in What did you build today (Pictures) ?:
@dbemowsk ], yes it's a fully printed case using PLA material.
I bought some nice and decent brass knurled from Banggood. Bought directly some M3 bolts made of stainless steel also at Banggood.The bolts you can get in different lengths.Nice. And thanks for the links.
How do you secure the brass knurls in the box? Do you glue them or press fit them or...?
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@neverdie, a very very easy handling. Just heat and melt them in the PLA
I use longer M3 bolts so that I can heat them up (in a flame of a stove or lighter)
and able to position them very accurately into the holes which are already there in the case it self. The knurled inserts have 5mm of diameter and I'm designing the holes @ 4.8 mm. If the inserts are heated you will melt them into the 4.8 mm holes and after cooling down...it solid and fixed in the case.
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Awesome! Thanks.
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@neverdie The ones that I have done in the past, I just heat up my soldering iron with the knurled piece in the tip for a bit, and then just press them into the holes and let them cool. I have done this too with just plain old nuts, but I like the knurled pieces better.
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We could make a new topic about making sensor boxes with projects already done and how to make them
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@gohan There is the 3D printing category
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So I have a basic switch plate done. I think I need to increase the font size on the button text a bit.
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@dbemowsk indeed there is, but nobody uses it
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So I now have 4 weather animations designed. Rain, snow, sunny and cloudy. The idea for now is to have the screen switch between 4 screens. Indoor temp, outdoor temp, current weather animation and current time read from my Vera controller. Here is a sample of my 4 weather animations.
Weather animation tests ā 00:51
ā Dan Bemowski
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I've build this temperature & humidity node.
It uses a Si7021 for the temperature and humidity, a power converter from a Li-ion cell to 3,3v. Voltage measurement with a voltage divider on pin A0.
I've removed the led and converter from the mini pro and also the power converter from the Si7021 (next time I will buy one for 3.3v instead of 5v). This really prolong your battery time, more then 4 times in my case. Looks like the node can run approximately half a year on a full Li-ion cell, scavenged from an old laptop battery.
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@woeka .... and the enclosure is from Surtronics.
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So I started work on a PCB for my OLED keypad scene controller. While designing it I wanted to make it with a few different switch configuration options. One design is the current layout like I have posted in my pics. One other proposed layout was one with up, down, left, right and select buttons. I designed it with 9 buttons which would allow for both of these configurations and more. Here is the proposed board:
If anyone can see any problems or have any other suggestions for this design, let me know.
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@dbemowsk said in What did you build today (Pictures) ?:
If anyone can see any problems or have any other suggestions for this design, let me know.
You had earlier lamented the low refresh rate. If you have the gumption, how about adding an SPI OLED interface such that it can do either I2C or SPI for the OLED? Having that extra option would only cost you at most 2.54mm in the vertical dimension.
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Recieved some PCBs today and one is the HLK-PM01 breakout which I will start working on for a project.
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@neverdie I'll look into that option. I'll have to see the difference in the pinouts between the I2C and SPI displays. Thanks for the suggestion.
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@neverdie I was exploring your suggestion of having both I2C and SPI options for the OLED display. One issue is that I do not have the SPI bus MOSI AND MISO PINS broken out on the headers. Because of this, to run it over SPI, I would have to modify the controller board, which I may do on a future release of the board.
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Finished assembling my HLK module...
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@sundberg84 Out of curiosity, How did you solder your thermal fuse on? What temperature thermal fuse did you use?
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@dbemowsk 74dgr C and solder it as usual (but quick and make it go down in temp before solder again). No problem. I have longer legs so it can touch the HLK module and that might help.
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@sundberg84 the last few I did on my scene controller power supply boards I ended up using an ice pack on it while soldering. I had blown a good handful of these till I figured that out. I use similar 73Ā°C fuses and keep the legs as long as I can and attach it to the side of the HLK case with a tiny dab of superglue.
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Holding the leg with a big pair of pliers is, in my experience, a good way to keep the temperature down. Something like this can absorb a lot of heat:
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@mfalkvidd I would agree, but when space is cramped, those are not always a workable solution. Great suggestion though.
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@dbemowsk true. But from the photo sundberg84 posted, there seems to be a lot of space so in his particular case it should work. Needle-nose pliers are also useful. They can't absorb as much heat, but they absorb some (especially if you put them in the freezer first ) and fit into tight spaces.
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@neverdie So because of your suggestion, I decided to explore the revision to the main controller board. I have not posted this revision to OpenHardware.io yet. Thought I'd get some feedback here first.
Some of the minor changes that I made were to the definitions of the headers. The headers now are labaled J1, J2 and J3. One other change was to combine the old J2 and J3 together into one header which is now designated J2. The biggest change was breaking out the MOSI and MISO SPI lines to the new J1 header. All changes are backward compatible with the old switch board hat. Here is the proposed board design. With the SPI bus now broken out, this will now allow the use of SPI capable displays and sensors such as the 128 x 64 OLED display for my current display/keypad board. I will make the changes to that soon.
The schematic is simple.
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@dbemowsk I thought they were all on the same board. I hadn't realized that they were separate boards. Also, at least on the schematic, the pinout on your pro-mini looks unusual.
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@neverdie It was one that I found on EasyEDA that was contributed by a user. Some of the other ones didn't have A4 and A5 for I2C on them. All parts are correct on the board layout though which is what matters.
My setup for these is 3 boards. Power supply, controller and switch/sensor board with faceplate. This is how the 3 boards stack together.
This setup allows me to build different faceplate boards with various switches, displays and sensors depending on what the needs are.
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So here is an updated board layout that with the new controller board layout will allow for either a 6 pin SPI or 4 pin I2C OLED display. J4 through J7 are jumper headers that tell whether you are using a 6 pin SPI or 4 pin I2C display.
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@dbemowsk Or maybe use solder jumpers instead.
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Building some loggers which i might sell later on.
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And want to make a tip about smd component organisation...
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@neverdie I thought about adding jumpers, but being that these are in-wall switches which are pretty much permanent, and the fact that because of space the OLED display needs to be soldered in place, there's not much chance of the display getting changed from I2C to SPI or vice versa. I figured that the pads could just be bridged one way or the other depending on configuration.
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@sundberg84 said in What did you build today (Pictures) ?:
And want to make a tip about smd component organisation...
I think we should make another topic for this kind of tips ? We could discuss pros and cons and give reference to online shops to buy items, your boxes are quite nice for DIP components and small breakout boards, where are they from ?
For SMDs components I went for the lab supplies on AliExpress, I started to sort my SMD chips using 5ml tubes and 3D printed holders, I need to print more holders to sort by categories as it's a bit messy at the moment. I put a bigger sticker on the side of tubes with more details as top sticker is pretty small Same holders can also holder bigger tubes for bigger stuff like here mini/micro USB plugs.
For resistors, capacitors, inductances, ... I went for lab tube boxes. I use smaller tubes (1.5 or 2ml) but they can hold probably thousands of 0603 or 0402 and even hundreds of the 0805 and 1206 resistors. I use different colors to differentiate size (and later precision/voltage/... when I'll have more boxes) and put bigger stickers on the lid of the box with information for each color.