voltlog – Page 10

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.

T-962 Reflow Oven Upgrades & Fixes | Voltlog #338

This is the famous T962 reflow oven coming from China, you might find it under a bunch of different brands, it’s available to order directly from China but also from a bunch of local distributors who are importing these ovens but in general they all have this list of problems which can be easily addressed for improving the performance as well as the safety aspects of operating one of these.

I got mine for about $180 shipped from Germany so there was no tax involved and it got here pretty quickly but you can probably find it for less if you are willing to wait a bit longer and get it from China. I used to run my own reflow oven based on a toaster oven but trust me, unless you invest in a really expensive toaster oven you’re not going to get the same performance as with one of these dedicated ovens. They’re not perfect as I’m gonna show next, they still have a bunch of problems but once we address those problems it becomes a decent oven with superior performance when compared to a toaster oven.

So let’s start with the paper tape insulation problem. This oven uses glass wool for insulation of the hot chamber and to seal that they used a combination of aluminium tape and paper tape, it really looks like the cheap painters tape. Now obviously the insides of this oven are gonna get hot and that paper tape is gonna start to burn and it will release fumes and a nasty smell. If you buy this oven and start using it right away without implementing this fix, you will need to vent that room most certainly.

Luckily this is an easy fix, the only thing you need is kapton tape. The idea here is to equip yourself with a pair of gloves and place the oven on a table that you can wipe clean when you’re finished to avoid contamination with the fine particles released by the glass wool. It’s best if you have some genuine kapton tape because it will stick better and you will have to remove all of the paper tape and replace it with kapton tape. You might also find some pieces of rigid cardboard/paper like material in there, I wrapped those in some kapton tape as well for protection against the heat and inserted them back where they were. Your oven should look something like this when you’re done.

InTheMail | Voltlog #337

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, I’m gonna start with this USB to RS232 serial adapter cable, inside this uses the famous Prolific PL2303 chipset and there is nothing wrong with that chipset but many people have had problems with that, including myself. Those problems are mostly related to fake chips, because going on Aliexpress and purchasing the cheapest usb to serial port cable adapter you can find will most certainly ensure you get a fake chip. Better cables that use genuine chips from prolific like this Ugreen branded one are more expensive but it should pay for itself in the long run by providing reliable connections when you need them.

I like this particular model also because it comes in a 2m length because sometimes you would use a cable like this to connect some large piece of gear and it might be helpful to have this 2m length of cable up to your computer.

InTheMail | Voltlog #336

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, I’m gonna start with this little guy, it’s a pulse oximeter. The model number, at least on the packaging, is YK-82C with a pretty recent date code as well, September 2020. So I got this pulse oximeter to keep around cause during these times, I think it’s a good idea to have such a device to monitor the level of oxygen in your blood, you know just in case you have an unfortunate event with well you know what, let’s not name it. I think this particular model is pretty nice, they also include an EVA carry case. It doesn’t come loaded with batteries but it uses 2 x AAA batteries which is nice. Single press to turn it on, it will auto power-off if there is no finger present for taking measurements, that’s pretty nice. Short press of the switch will cycle through a few different display modes in a couple of orientations, as we can see it uses one of those popular two color OLED displays.

Designing PCBs With Castellated Holes | Voltlog #335

Welcome to a new Voltlog, in today’s video we’re going to be talking about castellated holes and how you can create them in your CAD tool. If this term is new to you, it’s pretty simple, you’ve certainly come across them if you’ve ever played with a bluetooth or wifi module because those 99% of the time will use castellated holes, which are these semi-plated holes on the edges of a PCB. Having these connection points allows these modules to be soldered on top of a main PCB which contains our main circuit.

You might ask yourself why do we use castellated holes, why not use a simple through hole header as a board interconnect or just some simple SMD pads. Well in my opinion the most important reason is the relatively low difficulty for soldering castellated holes. If you think about it, having some SMD pads that go on the bottom of the PCB makes it pretty hard to solder, at least without proper equipment, you need to deposit solder paste on those pads, you need to get it in the right amount and then you need to have perfect alignment of the module on top of the pads which reside on the main PCB. Having these connection points underneath our module makes it very hard to align because you can’t see them. Also debugging such a module is going to be a pain because you won’t have access to all of those connection points.

So this where castellated holes improve, by having the plated half-holes at the side you can solder them even with a simple soldering iron, alignment is pretty easy because you can clearly see the connection points and debugging these is much easier because once again you can access them, you can do measurements with your scope probes or whatever instrument you are using.

Another advantage of having castellated holes on a design is to think of it like a building block, you might improve this building block externally or switch to a new building block that uses the same pinout and you just drop it into your system as a simple upgrade.

And believe it or not but having a module with castellated holes can lower your BOM cost in some cases because let’s say you need to use an RF module which might be 4 layers or a complicated system on module that may be 6 or 8 layer PCB with a powerful processor. Instead of building your entire system on an 8 layer PCB and assembling that complicated BGA chip yourself, you can buy the module ready made, it has castellated holes and you just drop that module into your system which may be a 2 layer mainboard or 4 layer mainboard that costs less.

InTheMail | Voltlog #334

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, I’m gonna start with this rather big development board based on an STM32F407 microcontroller. This particular microcontroller has 512K of flash memory and 192K of ram which should be enough to cover most needs. What I liked about this development board is that it comes loaded with peripheral interfaces like CAN bus, RS232, RS485, Ethernet, USB, SD Card and a bunch of IO so you can pretty much build any project you can think of. I’m particularly interested in the CAN interfaces so I’m planning to have a play with those.

While the product might be available from different sellers at different prices, there might even be different variations of this board I will place a link in the description to the seller where I got mine because it was the only one that offered a support pack for the board which contains schematics, documentation, example code, it even contains like a bundle of keil compiler with a keygen which ofcourse I’m not going to use, that would be illegal but you get the point, the seller will offer you a download link for this pack which is like 1.7Gb worth of documentation so I highly recommend it. It also ships the boards in these cheap plastic carry cases which are great for protection during transport as well as storage afterwards.

Designing A C5W Cree LED Bulb With Constant Current Driver | Voltlog #333

In a previous video I showed how I designed and assembled my own T10 style LED bulbs for the purpose of installing them in my car for the interior lighting. I was sick of these cheap bulbs I was getting from Aliexpress which didn’t last very long due to poor thermal performance and also they had this nasty blue tint color for the LEDs. The video I’m talking about is Voltlog #319, those bulbs have been installed in my car for the past couple of months, they are great. I love them and I’m pretty sure I will never have to replace those again.

Unfortunately T10 is not the only style of bulb that my VW uses on the interior lights, it also uses this style of bulb which is called C5W festoon for the lights on the sunvisor area. This comes in a few different lengths, I need mine to be 37.5 mm. So you can probably guess what I did next, I took the circuit I used previously and adapted the layout to fit the C5W outline.

ClonerAlliance 4KP Plus Capture Card Review & Teardown | Voltlog #332

Welcome to a new video, today we’re taking a closer look at this capture card which was sent in for this review by ClonerAlliance. This is their Flint 4K Plus model but they do sell other models as well so check out the links in the description to find out more and also watch this video till the end cause I have a giveaway which might interest you.

So let’s talk a little bit about the specs of this capture card, it’s 4K passthrough at 60Hz meaning that if you have a 4K signal from a camera or a gaming console, you can pass that through this capture card to a 4K monitor without losing any quality.

The interface is HDMI 2.0 for both the in and out passthrough, there is no HDR passthrough or capture, and the capture specs are 1080P 60fps maximum. Works on USB3.0 and USB2.0 but you really want to use it over USB3.0 to get the best quality, because I think over USB2.0 it switches to MJPEG codec while on USB3.0 it’s YuY2 uncompressed and it does support other frame rates like 24fps if you need that.

This capture card is UVC compatible, UVC means USB video class, this usb class describes devices capable of streaming video and so it’s universally compatible with pretty much any OS, it’s plug and play and it will show up as a camera device on your system which makes it super simple to use even with the simplest windows camera app.

Testing Kafuter Adhesives For Electronics | Voltlog #331

Welcome to a new Voltlog, in this video we’ll take a closer look at the various adhesive products that I could find and order on Aliexpress from this brand which has a hard to pronounce name, I would call this Kafuter but I don’t know, doesn’t sound right.

Since we deal with electronics on this channel, I’m particularly interested in how these adhesives would cope with use on electronics. As you may know in a typical product you may find different types of adhesives used: you might have some for securing wires/connectors, you might have a different type of glue used for securing big capacitors to stop them from flapping in the breeze, a different type of product for creating a seal against moisture, a different glue for securing trim pots in their final position.

And all of these products need to do their specific job while at the same time ensuring that they do not break down or become corrosive or conductive over time. I’m not gonna be able to give you any guarantees to that as my testing methods are not exactly industry standard so I’ll mostly be giving you like an overview of these cheap products that we can find on aliexpress and I will mainly recommend them for hobby use but if you have any experience with this company or it’s products, please do share in the comments below.