Welcome to a new Voltlog project video, today I’m gonna be presenting this little guy called ESP32 CanLite. This is a CAN hacking / development board based on an ESP32 and this is the results of my adventures into hacking the CAN network on my vw golf. I have not made any significant progress on the actual task of hacking the can bus other than what’s shown in Voltlog #342 simply because I got very busy with the professional work I do, consulting for various clients, you know just designing and building electronics but nonetheless I found the time to design and refine this board because this is already the second revision.
InTheMail | Voltlog #369
Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time and I must say that I’m worried about the future of mailbag videos given the new EU regulations on imports from China which are going into effect starting 1st of July here in Romania, I’ll have to do a separate rant video on the subject but there might not be any mailbag videos going forward.
I’m gonna start with this mailbag with a brand that you are already familiar with here on the channel, it’s difficult for me to pronounce this, I don’t know how it should be pronounced but these guys make affordable adhesives and related products. I haven’t had this one before, it’s the first time I’m getting the Kafuter K-5203 which is a thermal adhesive and to be more specific, their description is reinforced thermally conductive silicone elastomer with great adhesion, insulation and dissipation. And to give you some numbers they claim it can withstand variations of temperature between -60°c and +280°c and it has a shear strength of 30kg/cm3. The thermal conductivity is 1.2 watts per meter kelvin. I don’t need to tell you how to use this, it’s good for attaching stuff to a heatsink, in general stuff that also needs some form of bonding to the heatsink.
I Made A 10 Channel Thermocouple Data Logger – Voltlog #368
The idea for this project started when I got the T-962 reflow oven, after running a few tests I discovered that it had some hot-spots which meant some areas inside the oven were hotter than others and this could lead to trouble, you could get melted connectors in some places and cold joints in other places. Now it’s hard to tell how bad the situation is without doing some measurements so I decided to design & build this board which is capable of reading 10 thermocouples and logging the data. This way I could place the thermocouples inside the oven, something like a 3×3 or 4x2x2 matrix and I could get a sense of what’s going on inside the oven.
New Lab, New Voltlog Electronics Workbench | Voltlog #367
The most important part of this lab is obviously the workbench and this is something that I designed myself, I guess I can call this the Voltlog Workbench Design, it’s 2m wide with 80cm deep. The working surface comes out at about 95 cm from the floor. It sits on these adjustable feet but I haven’t even leveled it so far. Thanks to my friends at Welectron.com my working surface is protected with these nice premium ESD Mats. They are 100% and phthalates free, no bad smell, Heat and solder resistant, Chemical resistant, two layer ESD bottom side is conductive, top side is dissipative and they have this nice anti-reflective surface finish which is very comfortable to work on. I went with gray because it works best as a background for video shooting but you can opt for Blue as well. I’ll put a link to these in the description below, I highly recommend Welectron for their services & customer care and I highly recommend these ESD mats they are top quality.
InTheMail | Voltlog #366
Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. I’m gonna start with this EVA hard carry case, it has a rather strange shape but, this will fit one of these budget label printers perfectly. And if you are like me, using the label printer in the lab, where everything is clean, it might be perfectly fine to just keep it in a drawer but at some point a friend asked for my help to figure out the networking wires in a building, basically to identify every wire, crimp it and install some networking gear. Well when you start doing stuff like that you need a carry case for your label printer because it’s gonna get dirty, there will be dust and grime and the LCD might get scratched, you might want to toss this into your tools bag so that’s when I decided to order one of these hard carry cases, they’re fairly inexpensive so well worth getting one.A higher price printer might get one by default from the manufacturer but for these discount $30 printers you can’t really expect to get one from the manufacturer so you need to order it separately.
Upcoming Projects Teaser – Voltlog #365
Welcome to a new Voltlog, for today’s video I want to share with you some of the projects I currently have on my workbench, these are projects that still need some work to be done before they can be published but this will give you a glimpse of what to expect in the upcoming weeks on the channel.
I have these 3 projects on my workbench, the first one is a multi channel thermocouple data logger device based on an ESP32. This has 10 channels based on the famous maxim thermocouple interfacing chips and all of those are read by the ESP32 and data can be logged on an SD card. This should help me measure the temperature inside the T962 reflow oven that I reviewed a while ago in a grid to check how the heat is distributed inside the oven. I’m pretty sure there are some hotspots inside the oven and some cold spots, I don’t know if there is anything I can do at mechanical/design level to correct for them but it would sure be nice to be able to know what’s going on inside the oven and with such a board I can just connect 10 of these cheap braided K-type thermocouples from aliexpress and hopefully get some consistent readings but more on this in a future video.
The next one is an FT2232 based interface which I designed with the main purpose of allowing me to interface via JTAG to FPGA boards. The chip itself is capable of other protocols as well but my goal here is like I said to interface to various FPGA boards. I plan to dip my toes into the FPGA world and try to get a blinky up and running on an FPGA board for a start. I have designed the board to include a voltage level translator because the chip is running at 3.3V but whatever you connect this to might be running at 1.8 or 2.5V so there is provision for that and it uses USB Type-C like all of the boards that I’ve designed in the past year.
The third project is an ESP32 based CAN development board that I plan to use in my adventures of hacking the CAN bus on my car. I should be able to install this into my car to intercept, modify or send CAN messages while at the same time having two outputs which I can use to control various stuff with on/off 12V power. It has a dc-dc converter on board to step down the car 12V to 3.3V to power the board and if I remember correctly the chip was chosen to have a wide input voltage range to accommodate for any potential spikes on the 12V rail of the car.
How To Create High Voltage Isolation Slots In Kicad – Voltlog #364
Back when I published the video on the aquarium controller I built, someone asked how are these high voltage isolation slots or cutouts done in Kicad and I thought I’d do a short video to explain how you can design these into your next project but first, let’s talk about their purpose and whether or not you need them.
There is a common confusion between the terms creepage and clearance, myself I’m guilty of sometimes making this confusion but to give you a clear view on this, I found this picture online which shows everything very clear. Spacing between conductive elements through air is clearance while Creepage is spacing between conductive elements over an insulating surface.
By adding these cutouts in the PCB we are only increasing creepage distance, but if you would also like to increase clearance you will need to add some kind of barrier, and this is usually built into the enclosure and it will slide through the slot creating a barrier to prevent any potential high voltage arc to jump over the barrier by increasing the length.
There are also secondary purposes for putting cutouts into your PCB, I have used them in the past to create a thermal barrier or to accommodate various enclosure walls and features but I won’t talk about those today, those applications tend to vary a lot on a case by case basis.
But if you are using them as high voltage isolation you need to be aware of some aspects: first and most important remember to make the slot at least 1mm wide, if possible go with 2mm as this is required by some standards. There is a min width required by the fab house anyway because they are going to use a router bit on a CNC machine to cut that slot into the PCB and this may vary from one board house to another but I’ve seen 0.8mm mentioned by most PCB manufacturers. For example PCBway which is the sponsor of the channel, gives a min value of 0.8mm non plated slot and 0.5mm for plated ones. For isolation purposes you only want non plated ones.
There might also be other limitations on the size of the corner radius, I’ve not hit any of those so far myself but just imagine that router bit going around, it will not be possible to create very small features at your request.
InTheMail | Voltlog #363
Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. I’m gonna start with this little board which is an ethernet shield type of module which can bring TCP/IP connectivity to your project via a SPI bus. So this could mean any microcontroller that is able to talk over SPI to this chip can become internet connected. Now ofcourse these days the ESP32 is pretty popular, everyone is using wifi but for the highest reliability in network, wired connections are still preferred and there are also other microcontrollers that do not have a built-in ethernet interface so you need to add it externally with something like this. It’s fairly inexpensive so I think it’s worth keeping one of these around however interfacing to it might not be as trivial so it’s best to stick to the platforms that already have libraries written for this chip, like Arduino. Same as always, you will find a link to this in the description below the video.
Use These LEDs For Your Next Project – Voltlog #362
Welcome to a new Voltlog, this will be a rather short video where I will be talking about a rather common subject, LEDs. I’m sure everyone uses them in their projects but if you are like me you probably never cared about the efficiency of the LEDs you use for signaling the status of something on your microcontroller board. So what I was doing most of the time was picking the least expensive LED available while still picking a known manufacturer like Kingbright or Lite-on or Osram just to avoid quality issues. And that was my voltage rail indicator LED or my blinky LED for signaling some status. But this ofcourse meant I needed to drive those LEDs with a fairly high current of 15-20mA to get decent brightness out of them and that might be OK for numerous applications but in this video i want to talk about high efficiency LEDs and how your project could be nicer because of them.
ESP32 Aquarium Terrarium Controller – Voltlog #361
This project started when a friend of mine which has a snake terrarium asked for my help to build a system that is capable of regulating temperature and humidity so the snake can live in optimum conditions. I’m not necessarily a snake lover, I would rather stay away from these kinds of creatures but that doesn’t stop me from helping my friend.
I started by figuring out what he uses to control temperature and humidity and it turns out there is some sort of a lamp to provide heat from above, some sort of mains powered stone that heats up and a water fountain, probably one that runs with fog to control the humidity. All of these are mains powered and only need simple on/off control which makes things simple when designing the electronics board.
In terms of digital control I figured it would be nice to have to be able to update the set points and check on the status values wirelessly so I went with an ESP32 modules. This also helps to add an extra layer of protection to keep the user away from the dangerous mains voltages present on the relays. I can have the whole board, enclosed in a plastic box so the user never goes near the mains voltages.