Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. We’re gonna start with a set of 3 prying tools from Best which is kinda of known in the mobile phone repair business, it’s a Chinese brand that sells this kind of tools. I like these because they have a nice rubber handle which provides a good grip for when you’re trying to pry open an enclosure.
Voltlog #218 – Shower thermometer teardown after 10 months of usage
Welcome to a new voltlog, today we’re going to be doing a bit of a destructive teardown on this shower thermometer. You might remember this from 10 months ago in voltlog #172, I got it 10 months ago and ever since it’s been running in my shower and I’m interested in seeing how this looks on the inside after 10 months of usage.
After about 2-3 months of usage I’ve noticed I was getting different temperature readings for the water that I was previously considering warm enough but at that time I figured it was because of the change from summer to winter and I blamed it on the ambient temperature. However I now checked with a thermocouple and the result was pretty bad, the shower thermometer is way out.
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 #216 – InTheMail
Welcome to a new voltlog, the series that will touch both your passion for electronics and your bank account at the same time.
We’re gonna start with this multimeter thermocouple which I got from ebay, it’s brown, it looks familiar to those who have a fluke multimeter, and yes it’s branded Fluke. However I got this from ebay for just a few dollars delivered from China so it might as well be fake but honestly who cares, it’s just a thermocouple, it’s gonna work just fine even if it’s a fake one. The think is I got my fluke 87 used without original packaging so it was missing the thermocouple but now I can plug this in and measure temperature as well.
Voltlog #215 – Is a genuine Hakko T12 tip much better than fake one?
A while ago in voltlog #186, I compared the TS100 soldering iron to the STM32 T12 based soldering station and the results were pretty interesting to watch, if you haven’t seen that video there will be a link in the video.
As we all know the market is flooded with counterfeit or replacements for hakko products. So I’ve always wondered how does a genuine T12 cartridge tip compare to a replacement or fake hakko tip. So today, we’re going to test a genuine T12 tip vs a replacement one. This is my genuine tip, I got it from an authorised reseller, the cost was $20, shipping excluded. As you might notice it says T15 on the packaging but don’t worry there is no difference between T12 and T15 tips, except they use a different part number depending of the markets. T15 for EU and US markets and T12 for Asia as far as I know.
Voltlog #214 – How bad is a fake apple lightning to 3.5mm audio adapter?
Welcome to a new voltlog, today we’re taking a look at these lightning to 3.5mm audio adapters that you have to use ever since apple removed the 3.5mm jack on the iphone. So you know the story, apple removed the jack and said it’s because they will free-up space inside the phone and it makes it more waterproof but if you ask me that’s bullshit, they removed it to force people to buy bluetooth headphones. But anyway we won’t go into that, this video is about the adapter that they now give people to still be able to use the 3.5mm jack for audio.
This made me wanna take a closer look so here are the two adapters, the plan is to connect a 3.5mm jack, this will provide me with some contacts where I can probe with the oscilloscope. I’m gonna generate a known constant waveform from an app and we’re going to measure that and compare between the two adapters.
Voltlog #213 – InTheMail
Welcome to a new voltlog, the series that will touch both your passion for electronics and your bank account at the same time. We’re gonna start the video with a battery charger from Liitokala, model number is Engineer Lii-500. It works with an external 12V power supply which I opted not to get because we all have a bunch of 12V adapter from old equipment.
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 #211 – Joulescope DC Energy Analyzer Review & Teardown
Welcome to a new voltlog, today I’m excited because we’re going to take a look at an awesome piece of instrumentation. I’ve received a pre-production demo unit of the Joulescope DC Energy Analyzer.
The joulescope is a low cost precision dc energy analyser which is currently on kickstarter so check the links in the description of the video for the kickstarter campaign because it has a massive discount from the retail price. The joulescope has circuitry for measuring voltage and current, from which it can calculate power and then it can integrate power over time to calculate energy. The current measurement range is from 10A al the way down to 1nA, that’s a huge dynamic range which makes it very useful if you plan to measure the energy consumption of a device that has mixed behavior for example an esp32 that will wake up, do some activity and then go back to deep sleep.
The joulescope works with a software companion that has a multimeter view and an oscilloscope view which I find very useful because it will allow you to time correlate measurements of voltage and current. That can be extremely useful when determining the energy usage of your device.
Voltlog #210 – 946C Hot Plate Review & Teardown
Welcome to a new Voltlog, today we’re gonna do a review and teardown of this hot plate which was supplied for free by banggood.com. So you would use something like this to preheat a pcb, to prepare it for desoldering an IC or even for reflow soldering a board. As usual there will be links placed in the description below which I encourage you to check out. There is a 100x100mm version at 400W and a 200x200mm version which I have here at 800W.
If you haven’t worked with a multi layer pcb you might ask yourself why do I need to pre-heat the board. Well modern devices uses a high number of internal pcb layers so desoldering something from those might be harder if you only heat the board from the top with hot air, it might take some time until the IC reaches desoldering temperature because the heat is sucked away by the internal copper layers.
This could be bad for the board and the IC because you will need to increase the temperature of your hot air station above the normal working temperature to compensate for that and in the process you might damage the board or the IC. Such a tool allows you to bring the board to a higher temperature without creating any hot spots, and then you can just heat with hot air from the top the are where you need to work.