Welcome to a new Voltlog, In this video we’re taking a look at the OWON HDS242S which is a dual channel 40MHz portable oscilloscope coupled with a 20000 count true RMS digital multimeter and an arbitrary waveform generator capable of 25Mhz sine and 5MHz square wave, all in this portable format with a 3.5inch color TFT display. As part of their line-up you can also get the HDS272S which bumps the oscilloscope up to 70Mhz. You can also get these without the function generator option and those would not have the ending S in their model number.
Author: voltlog
I failed AGAIN at designing this FT232H circuit | Voltlog 379
This is my first attempt at designing with the FT232H and if you’re wondering how the FT232H is different from the standard FT232 or other typical usb serial converters, well it’s different because it has a thing called MPSSE which stands for Multi-Protocol Synchronous Serial Engine. This allows it to emulate a variety of serial protocols like: JTAG, I2C, SPI or general purpose bit-bang. So a couple of years ago I designed this breakout board and almost everything was right except for the fact that I got the usb data lines mixed, which prevented the chip from enumerating correctly on the USB bus.
So this year because I got a couple of FPGA boards I thought why not redesign that board to fix the data line issue and add a couple new features that would make it a very useful tool to have in the lab. And so I started designing this new board which I called VOLTAG and there a couple of things that I absolutely wanted to have: the first one was USB type C, I decided to only use USB Type-C sometime at the end of last year so every new board needs to be on USB type C, if it has a USB connection at all and the second thing I wanted to have was the ability to level shift the JTAG signals.
InTheMail | Voltlog #378
Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. I have some news regarding the import of our packages from Aliexpress into the EU. It seems our Chinese friends re-grouped and found a way to improve things for us. So half of my packages are still coming through as normal with quote marks, because I’m there is a double taxation happening, the electronic system is not operational here yet so they charge VAT a second time when you receive the package plus a 2 EUR handling fee but the other half o the packages started arriving grouped into larger bags through EU routes without having to go through customs. I think that’s a plus because it avoids the double taxation that was happening here plus I get more packages at once, less hassle. I’ll keep you updated in future videos on the status of these packages.
I built the ultimate electronics workbench using just a screwdriver | Voltlog 377
In this video I’m gonna show you how I built this awesome electronics workbench using just a screwdriver, yup, you’ve heard that right, you don’t need any other tools, just a screwdriver. In my opinion this is the ultimate electronics workbench, it has just the right height for me, it uses the available space as efficient as possible, it’s very strong and best of all it’s modular and upgradeable: meaning you will be able to grab this project and customize the size of the workbench to fit your available space or your particular needs. Oh and did I mention that it costs less than those commercially available off the shelf workbenches with similar specs? Stick with me in this video and I’ll share the full details on how I built mine.
You Need This Instrument Right Now | Voltlog 376
Inside the box we are greeted with the instrument and I must say I expected a compact unit but this blows my minds, it’s actually smaller when you get to see it in real life and it feels kinda strange because it has all the visual cues of a professional instrument with the exception of size, it’s something new but I expect to see more of these miniaturized instruments in the next couple of years. You also get a power adapter and one that apparently has all of the safety certifications and it comes with these exchangeable socket adapters, you get the USB power lead which is just an adapter from USB to barrel jack and you also get two coaxial cables, that’s pretty much all you need to get started.
I have the ETG962E 60MHz model here but right from the start you shouldn’t set your expectations too high just because you see the 60MHz bandwidth mentioned because take a look at the sample rate, it’s 200MSamples/sec so at the max output of 60MHz you’re only getting roughly 3 samples per second which isn’t enough to describe a clear simple waveform, not to mention some more complicated waveforms. I mean it might do ok with a sine wave just because it can specify the top and bottom points and with a slower rise time it will automatically turn it into a sine wave but that’s pretty much all you’re going to get at the max output of 60MHz. So they’re kind of pushing the max spec of this unit for marketing purposes by specifying it at 60MHz when in fact it can do that for anything other than a sine wave.
It’s pretty obvious that you need to cut some corners to be able to offer such an instrument in the $150 range shipping included but as long as you are aware of these limitations, it’s still a pretty good offer, actually it’s the best offer on the market just because there isn’t anything like this available with similar specs in a similar price range and with the same quality.
Ynvisible Ultra Low-Power Display Technology – Voltlog #375
Welcome to a new Voltlog, today we are taking a look at some pretty interesting display technology, this evaluation kit was sent to me by the company named YNVISIBLE for the purpose of this review, they developed this display technology based on Electrochromism, this is defined as the property of a material to change color when voltage is applied. I’m sure this sounds familiar because similar properties of materials are used in e-paper or e-ink displays, they both reflect ambient light but in the case of e-ink the technology is different , as e-ink display are based on electrophoretic properties.
So this is what you get inside the kit, I like how it’s put together and you can get started evaluating the technology as soon as you open the box because, besides providing you with a wide selection of display examples based on their technology, you also get some ready to go boards to drive these display units.
Before telling you more about the display technology let me quickly connect one of these to the demo board to show you how it looks. I noticed two things immediately, it does take some time for the cells to change color but it’s really simple to drive these as you can connect them directly to MCU pins and just drive them directly. For example this 3 segment display, has a 4 pin connection, one common pin and one connection for each segment. Drive it high or low to go from color to bleach state. So you start to imagine how this can enable some very low cost devices to be built.
Aneng AN888S Multimeter With Bluetooth Speaker Review & Teardown – Voltlog #374
Welcome to a new Voltlog, today we are taking a look at this true RMS auto-ranging bench multimeter unit from Aneng but as we know we typically find the Aneng meters being sold under other names, different colors so for example this one is also available under the model name ZT-5566 and ZT-5566SE which I’m not really sure but might be able to provide spoken measurement via it’s built-in speaker while the one I have here only has bluetooth speaker functionality. Yup you’ve heard that right, it’s a multimeter combined with a bluetooth speaker. This unit was provided for free by banggood.com for the purpose of this review and if you would like to order one after watching this video, please consider using the link I’ve placed in the description of the video.
This is a 20000 count meter and the dc voltage accuracy is 0.05%+3 counts, dc current 0,5%+3 counts, an update rate of 3 measurements per second, it can also do ohms, capacitance, diode, continuity, frequency, duty cycle. There is no CAT safety rating printed on this meter, they probably don’t bother with that any more but we should be able to evaluate general safety measures later in our teardown. I don’t see myself playing music through this while working on my projects but I could definitely see myself playing one of my favorite podcasts while working on some electronics, like for example TheAmpHour show which I often listen to while assembling or debugging boards.
InTheMail | Voltlog #373
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 have some news regarding the import of our packages from aliexpress into the EU. As you may have noticed Aliexpress started collecting VAT according to the new IOSS system and you would expect that an EU member country would have the system in place to process these packages because you know they asked for this system, they created it so you would expect the would have the system ready.
But it’s a complete shit show over here, there is a double taxation happening, the Postal company here slaps a 1.6 EUR fee for processing packages and also collects VAT according to the value declared by the sender on the package, even though you already paid VAT and you can prove you paid it with the invoice that Aliexpress provides.
When asked why we have to pay the VAT twice, the Postal service said, they have the system in place to process packages coming through the IOSS system automatically and avoid double taxation but the customs authority doesn’t have it’s system ready, hence the issue of double taxation. And you can guess what the customs authority said when I asked them why we are being taxed twice, they said, it’s all good, we shouldn’t be taxed because tax has been collected already and yet the postal service is not releasing the packages until the fees are paid.
It seems that right now, the only way to avoid double taxation is if you do the import papers yourself or if you use a 3rd party company that offers those services but their fees start at about 50EUR per import and the forms aren’t exactly easy to do so yeah, cheapest option right now is to just pay the postal service fees and get the packages. I’ll share some more info once I have it but right now, at least here in Romania, it’s as bad as it can be and the authorities don’t seem to have a solution. But enough ranting, let’s get on with the items I received.
Uni-T UT501A Insulation Tester Review & Teardown – Voltlog #372
Welcome to a new Voltlog, for today I’m going to review & teardown this Uni-T Insulation Tester, the model number is UT501A. We’re going to start with a general introduction and then continue with a teardown and presenting some real world test scenarios. If at any point you are interested in ordering one, please check out the links I’ve placed in the description below.
So, like the name implies, this meter is good for testing insulation resistance but why would you need to do that? Well you would want to test the insulation resistance of a particular circuit or piece of machinery immediately after first installation or repair or through its service life to discover potential problems before they occur.
Let’s take for example the winding of a motor, every turn of copper wire is insulated but because of stress, harsh operating environment, over time, the insulation might start to fail and by testing regularly you can start to nice if the insulation resistance starts to drop and you might be able to service that piece of equipment before catastrophic failure.
Or another good example is when you wire up the electrical installation for a new home. During the installation procedure or during the construction period, accidental damage might occur to the wiring so it’s good practice to test for insulation resistance before you start using the new installation.
Pokit Meter Review – Voltlog #371
This is a bluetooth pocket multimeter which means it doesn’t have a display, it uses a smartphone/tablet app to display the measured data and it can do almost everything that a basic meter does: it can measure ac/dc voltage but no true RMS capability on this model, ac/dc current, resistance, continuity, diodes and as a bonus it can also do data logging and it has an oscilloscope mode but with a more limited range of values & functionality given its size. I find this pretty cool, because they managed to build so many functions inside such a small package like I have not seen pocket multimeters that can do data logging so far.
Right from the start you realize why they call it a pokit meter, it’s basically the size of a small puck, less than 5cm in diameter and about 17mm thick. Inside the box you get the meter itself, a pair of J-clips, a spare fuse, a small neoprene carry case and a quick starting guide. The first thing you need to do is to remove the battery seal and you have to twist the battery cap for release and then pull on the small insulating paper which then activates the CR2032 battery.