In this video I replace some of my old crappy 4mm banana connectors with some new Hirschmann and Staubli, high quality connectors. These should be more reliable and provide a low resistance connection between my test gear allowing me to pass high currents without any issue.
Category: Soldering
Voltlog #249 – Making Some USB Serial Converter Boards With CH340E (part 1)
Welcome to a new video, today I’m building a bunch of usb to serial converter boards because if you are into electronics and microcontrollers you will for sure need a bunch of usb to serial converters to connect your boards to a computer for example.
The idea for building these boards started when I found the CH340E converter chip on aliexpress, I like several things about this chip, it was small because it comes in MSOP10 package, it was cheap at about $0.40 a piece and it requires minimal external circuitry, in fact it only needs an external bypass cap.
Voltlog #243 – TS80 VS KSGER T12 Soldering Iron Comparison
Welcome to a new Voltlog, yet another soldering iron comparison video and today it’s between the TS80 and the KSGER T12 station. Everyone knows the TS80, is quite a popular portable soldering iron, works with USB type C input, it needs a quick charge compatible adapter to reach full power and it’s quite a capable soldering iron. The drawback is the cost of the tips, it uses this proprietary type of tip and the cost is about $20 a piece.
On the other hand we have the KSGER soldering station which I reviewed in Voltlog #232. This station has a built in power supply and uses the well known T12 tips which are widely available on aliexpress, for example you can get KSGER T12 branded tips for about $3 a piece. I think that’s important, because I have 2-3 different tip shapes that I use regularly and maybe another 2 or 3 that I use occasionally for odd jobs. You can’t just rely on a single tip shape and purchasing the same number of tips for the TS80, is not going to be cheap.
Voltlog #240 – ESP32 PIR Motion Sensor With Deep Sleep & MQTT
Welcome to a new Voltlog, in this video I’m gonna show you how I designed and built this board which functions as an esp32 based, battery powered PIR motion sensor. So I started by designing the circuit, I used some common building blocks, I added the ESP32 with it’s bypass caps, some test points and the programming circuit with auto-reset, I then added some connection points for the PIR sensor, an RGB LED because why not have a nice way to signal this is one of those very small digital RGB leds, it’s just 20x20mm, it’s connected to 3.3V even though it’s only rated for 5V so I’m hoping this is going to work even on 3.3, it’s also worth having a temperature/humidity sensor to also sense that in whichever room the node will be placed and finally the power supply circuit which is a simple low dropout regulator with an 18650 battery as the input.
I did not include a battery charger circuit on this module, because I wanted to keep things simple, I’ll have a battery socket so I can just remove the 18650 cell and charge it separately plus the whole circuit should run in sleep for extended periods of time giving me a long operating time so i wouldn’t have to charge the battery too often.
Once the schematic was finished I did the board layout in a hurry so it’s not exactly pretty or optimized
but I tried to move the esp32 antenna to the side, to place the PIR sensor in the top side as the module will probably sit vertically, I tried to place the temperature sensor in the bottom side to keep it away from any components that might get hot and also placed some isolation slots for the same reason.
You should check-out revB of this board, I made some improvements present in the video below.
Voltlog #234 – The Problems I Found With The KSGER T12 Soldering Station
In a previous Voltlog I reviewed this KSGER T12 soldering station, it was the first station I got my hands on from this manufacturer, it’s version 2.1S and I was pleasantly surprised by the features it has. If you haven’t seen that video I will link it on screen right now. Since then I’ve been using it as my main soldering station and I’ve been pretty happy with how it works but some of my viewers who have been using these for longer have pointed out a few things I missed in the video so this will be a quick update video to show the things I’ve missed previously.
Voltlog #230 – Guidelines For Board Level Temperature Sensor Layout & Placement
Welcome to a new Voltlog, today I’m gonna show you some techniques that you can use when doing temperature measurements. Typically you will want to measure either the ambient temperature or the system or component temperature. Depending on one of these goals you are going to follow different design rules to achieve that. And to better illustrate the problems, I have these 3 pcbs which have exactly the same electrical circuit but with different layouts on the pcb.
The boards consist of an esp8266 and a digital temperature sensor and you might expect that since all 3 boards are placed so close together, they should all indicate the same temperature but that is not the case as we can see on this graph we are getting 3 different temperatures and only one of them is close to the actual ambient temperature measured with another thermometer, so why is that happening? Well the answer lies in the layout of the PCB and that includes component placement, copper planes and various other elements on the PCB.
Voltlog #229 – What’s The Smallest Digital RGB LED?
Welcome to a new voltlog, today we’re talking about RGB LEDs. Everyone knows and probably uses digital RGB LEDs these days because they’re convenient, you only need a single pin to control then, they can be chained one after the other creating long addressable RGB strings, you don’t have to worry about driving them with constant current, in fact they even have digitally controlled brightness settings so they’re pretty convenient.
Since these are digital, they have a built-in controller chip, and if we take a closer look at one of these LEDs which comes in a 5050 package, we can see the driver chip and the 3 LEDs red, green blue with their corresponding bonding wires. There are two popular drivers chips the WS2812 and the SK6812 and each of these might have different revisions as well. The WS2812 was the original one on the market and then the SK6812 appeared and is considered a clone of the WS2812 but brings some improvements. The SK6812 has doubled the pwm frequency at which it drives the LEDs which is always welcomed as it helps with reducing flicker and also the timing requirements are a bit tighter but existing WS2812 libraries should work fine with the SK6812.
Voltlog #217 – Constant Current LED Driver Boards Assembly & Testing
Welcome to a new voltlog, today we’re going to assemble some prototype PCBs for different constant current LED Drivers. I’ve designed and ordered these pcb’s a while ago, the goal is to test different constant current led drivers I have ones that are switch mode and ones that are linear and I wanted to see if I can get away with using the linear ones, because there is a significantly lower part count at the expense of burning energy away and generating more heat.
I haven’t ordered a steel stencil for these pcbs, I’m gonna hand assemble them, I’m gonna use some of this mechanic leaded solder paste which comes in a syringe and then I’m gonna reflow the boards over a hot plate. One hint here about the paste, if the syringe is very old, the paste might get dry which will make it unsuitable for the job and not to mention hard to push out of the syringe so try to keep the paste fresh by storing it in a fridge and replacing it when it starts to dry up or separate inside the syringe.
These two boards will be powered from 12V current through LEDs will be 25 mA and the total string voltage is 10 V calculated with a typical led forward voltage of 2V. That means the difference of voltage will be dissipated on our regulator and that can be calculated 12V-10V we have 2V dropping on the regulator times our current 25mA and is equal to 50 mW.
Voltlog #212 – DIY Silicone Lead
Welcome to a new Voltlog, today I’m making a nice flexible extension lead for my TS100 soldering iron. I know many of you might not be interested watching me build such a simple extension lead but I think you could at least get a good tip on this type of silicone cable and where to get it.
I was searching for silicone cable with two wires that came somewhat attached in a single wire and all I was finding was double insulated silicone wire on aliexpress which was not cheap and at the same time I was worried it wouldn’t be as flexible and thin.
Until someone recommended in the comments I should try this power supply wire for tattoo machines. You can buy this stuff from ebay or aliexpress for under $3 shipped.
Voltlog #209 – Cheap Electric Desoldering Pump Teardown
Welcome to a new Voltlog, today we’re doing a teardown of this electric desoldering pump, which I showed in a previous mailbag video. This had a major when I powered it one, in fact I’m not gonna try to power it on again because I don’t want all that smoke to fill-up my lab again.