Electronics and technology blog    /    Materials for January 2022 year

This is the second battery from Liitokala. It’s the same size, but has a slightly higher capacity and a claimed continuous current of 20 A. You could even say it looks like a pretty good capacity-to-size ratio. Inspection, tests, graphs, conclusions.

Back in early November last year, one of my readers got in touch and offered to let me test several batteries from the well-known LiitoKala. Since I'm always interested in testing different batteries, I of course agreed. In the end, he ordered four batteries to be delivered to my address, and today I'm looking at the first one.

A while ago, I wanted a simple yet versatile device for my workshop. Then I happened to come across this one from Vapcell, got interested, and ordered it for a review. Today I can show you what it’s all about. Inspection, teardown, tests, conclusions.

I have a couple of small trim routers, and I came across a link to collets for them in the comments one day—not just the standard 6.35 mm size, but two additional sizes as well: 6 and 8 mm. I thought, why not order them? They might come in handy.

A while ago, I came across a review of a fairly basic pulse oximeter and thought, why don't I have one yet? So I ordered one. A brief look at the purchase and a few conclusions.

Today I'm reviewing a typical Chinese power supply made to look like a laptop charger—that is, as a replacement for a laptop's original power supply. A look inside, some tests, a minor modification—but overall, everything was predictable even before I placed the order.

Our team is developing a cloud IoT platform, and we regularly build small projects to test its features: “smart” relays, outlets, string lights, and so on. Some projects turn out to be so interesting that they grow into full-fledged products. We decided to tell you about one such case.

Another roundup of assorted products—some I just came across, others I ordered, sometimes more than once.

This is my second pair of batteries from Vapcell, and unfortunately, it looks like it will be the last for now. These batteries don't stand out for their capacity, but they do deliver an impressive 35A. Inspection, tests, graphs, comparisons, and conclusions—as usual.

A while ago, I came across a review of a clock that synchronizes via NTP. Since I’m generally fond of clocks, I couldn’t resist and ordered one for myself. I actually ordered it from a different store, where it was a little cheaper, but that doesn’t really matter here, since they’re identical.

It's been quite a while since I last reviewed any batteries, so Vapcell sent me a few new test subjects. Today, we're looking at the first pair. I can't really say anything bad or good about them. They're perfectly decent batteries, but nothing particularly special.

I've already written a couple of posts about spot welder controllers that work with supercapacitors, but today I'm going to talk about a more "classic" setup with a powerful 50 Hz transformer. I'll show you the controller itself and a small example of how it's used in a real spot welder.