Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. This will be a great year hopefully, I’ll make sure to do my part and provide you with the best mailbag videos on youtube. We’re going to start with this utility knife, it’s the xiaomi type knife that I showed in a previous mailbag but I liked it so much that I got another one, I’ll keep one in my laptop backpack for general stuff like opening packages and one at the workbench for general purpose stuff. The body is aluminum, the build quality is great, they feel perfect in the hand, you can get them with a set of super sharp replacement blades and they’re pretty cheap with everything considered so if you haven’t already got one, I highly recommend these, you can find the links in the description below the video.
JTAG Adapter PCB 20pin 2.54mm to 10pin 1.27mm – Voltlog #347
Welcome to a new Voltlog, this will be a rather short project video, I thought I’d start the year with something simple. If you’ve ever used JTAG before, either to program or debug an ARM processor, or something like an ESP32 or maybe to load a bitstream into an FPGA, you’ve likely encountered the ubiquitous 20 pin JTAG connector which is this 2×10 0.1inch spaced connector. It’s a rather large connector, it takes up a lot of space on a PCB, you don’t really need that many pins but you can’t go without it because it’s usually present on the fully featured programmer/debugging tools. Here is an example: this is an ST-Link V2, or to be precise a cheap clone from aliexpress but for the purpose of this discussion it doesn’t matter, it looks the same as the original and it has this 20 pin JTAG connector.
And to some extent this isn’t really a problem if you are using big development boards like this STM32F4 dev board that I got from Aliexpress. This features the same 20 pin connector for programming so it’s a matter of connecting a simple ribbon cable and you’re up and running. However, most modern boards that you are going to be designing might not have enough space to install such a big connector, you might for example use the simpler 10 pin JTAG connection, cause you don’t even need that many signals, most of the pins are GND anyway on the 20 pin connection. And instead of using 2.54mm pin header you can use something smaller like half the size, 1.27mm, and this can save a lot of space on a board.
InTheMail Stats For 2020 – Voltlog #346
Welcome to a new voltlog, this is the annual review to present some stats on the number of orders and spending with regards to my activity. The InTheMail videos are my most popular videos so as you can imagine there is quite a bit of spending and orders placed behind the scenes. Same as last year, please let me know in the comments if you have any stats on your own purchases, I would love to get a feel for how everyone else is doing.
This year I’m not going to show any stats for ebay, I’ve stopped using ebay, I do most of my orders on aliexpress.com starting with 2020 and I also place a few orders on banggood.com. In fact I’ve also stopped placing links to ebay items in my mailbag videos because I don’t really use the platform anymore.
InTheMail | Voltlog #345
Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. We have a selection of different items received in this mailbag, some of them will probably go out as Christmas gifts to friends, some I’ll keep for myself. Let’s start with this ESP32-S2 development board.
This is the official Espressif dev board and is called ESP32-S2-Saola. It comes in two variants With UFL connector installed so you can use an external antenna or without the UFL connector installed to use with built-in antenna. So the reason for getting this development board was to play with the USB host functionality of the ESP32-S2, I’m working on a project where I have this usb device that creates a virtual serial port over USB. I would love to have that device connected into something like this and create a bridge for that serial port on the local network.
Smart Christmas Tree With RGB LEDs & ESP32 | Voltlog #344
For this year I wanted to add a personal touch to our Christmas tree and so I have started thinking about what features it should have. Lately I’ve been playing a lot with HomeAssistant and so the obvious path was to put an esp32 in there so that I could control it from the app. Next I thought about making it battery powered but considering I wanted to use at least 10 RGB LEDs and I also had the ESP32 in there which is kinda power hungry, the kind of battery needed to run the whole system for a decent amount of hours before needing a recharge would make the whole thing too heavy so I instead went with usb power because I always have a socket available at the bottom of the tree to power the tree lights so I could easily add a small 5V adapter and run a micro usb cable through the tree. So these were the main decisions I had to make regarding this project and the rest is just support circuitry.
Would I still recommend these products after using them? | Voltlog #343
In this video I’ll be going over some of the most important gear I have in my lab, this is stuff I have reviewed in previous videos but I want to share my thoughts after using the gear for extended periods of time. Sometimes you might discover stuff that you miss in the original review video.
VW Can Bus Hacking With SavvyCan & Cantact – Voltlog #342
In this video I’m gonna walk you through the process that I use for hacking a VW cluster CAN bus(PQ35 platform). The tools that I’m going to be using today are very accessible price wise and open source on top of that. As hardware I’m going to be using the Cantact usb to can bus adapter, this is going to allow a computer and operating system to access and communicate on the CAN BUS. As software I’m going to be using Savvycan which is once again an open source GUI tool for hacking and reverse engineering CAN BUS data.
InTheMail | Voltlog #341
Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. Checkout the items I received in this mailbag which include: Some Sonoff S20 & S26 smart plugs, Mechanic syringe aluminium plunger, Vetus eye candy tweezers, Xiaomi Fizz aluminium utility knife, a couple of short and flexible HDMI cables, some Kafuter adhesives, 18650 battery spacers, EVA hard carry cases, plastic organizers, Scotch Brite wheels for the dremel tool, diamond sharpening stones, and some o-ring assortment kits.
Best BST-933B JBC Clone Soldering Station Review & Teardown | Voltlog #340
Soldering tools is a big subject as there is no electronics bench or hobby without a soldering iron hence why I have several videos on the subject and why I will continue to do such videos when new tools are presented. Everyone knows and probably wishes for a JCB or Metcal station since they are very well known in the industry, they are reliable and most importantly very capable soldering stations but their price tag keeps them out of reach for the average hobbyist.
That’s why clones of the big names appear on the market and they can be bought for half the price of the original one, sometimes even less. That’s why the KSGER T12 soldering stations are so popular and why I use them. They support the original Hakko tips and so they provide identical performance to a Hakko station as long as you install a good quality T12 tip.
Which brings us to the subject of this video, this is the Best 933B, which is a clone of the JBC CD-B series compact soldering station. This has been on the market for a while but I recently got a chance to review this station when banggood offered to send me one for free. I would appreciate it if you would check out the links I place in the description, this will ensure I can get more gear to review in the future. Price wise, if you were to order one of these it would cost you about half the price of the original JBC station. Depending on where you order the original one is around 400EUR while the Best station is about 200EUR on banggood.
T-962 Reflow Oven Custom Profile Calculator | Voltlog #339
In the last video I showed you how I upgraded the T-962 oven to fix some of the issues that were present on this oven. I also mentioned that there is an option to configure a custom reflow profile with this oven and that’s probably something you’re gonna have to use sooner or later because there are so many options of solder paste on the market and not only that but also there is variation between different ovens so it’s likely you’re gonna have to tweak that.
So in this video I’m gonna show you how to define a custom reflow profile in the open source unified engineering firmware. Before doing any actual configuration on the oven you need to start with the specs of your solder paste. For this example let’s assume we are working with the NP545 series from Kester, we need the datasheet of this product to check out the recommended reflow profile. Inside the datasheet we can find the recommended graph, it’s an unusually small one for this paste but luckily we can zoom in and increase the size of the graph.
At this point I recommend you grab a screenshot of this profile and import it into your favorite img editing tool because we need to draw some lines on this graph to extract some values. First I added a scale on the Y axis with a line at each 5 points. Then I added these lines to plot the absolute values on the Y axis. So we now have a set of temperature values for every 30 seconds of the profile but the firmware on the oven, the procedure for inputting a custom reflow profile expects data points every 10 seconds so we need to somehow extrapolate our values to generate more points in between.