A review of four Switch-mode Buck (Step-down) converters with USB ports

While designing a project that required 5v USB power ports from a much higher voltage source (eg. 12v or 24v), it occurred to me that there are circuits already designed to do this. In fact, not only do they exist as low-cost, easy-to-purchase modules, but some of them already have the USB port soldered onto the board.


Four Step-down converters with USB ports were picked out and reviewed in an attempt to find “the best cheap USB switch-mode step-down converter” for 12v power supplies.

Continue reading A review of four Switch-mode Buck (Step-down) converters with USB ports

Best beginner’s auto-ranging Digital Multimeters (DMMs) compared and reviewed

With the current DIY/Maker movement in full swing, one thing that almost all of us need is a good Multi-meter. When shopping for one, it was decided right away that a good entry-level multimeter for beginners had to be:

  • Digital
  • Auto-ranging
  • under $50

Why these 3 criteria?

Digital for high precision, Auto-ranging to eliminate the need to switch the dial every time something changed, and $50 maximum to keep this within the budget of most DIY’ers/Makers like you and me. (As an aside, the requirement for an Auto-ranging feature also makes the minimum around $20.)


After perusing Amazon, it was discovered that 8 models fit this criteria. The biggest problem was that all 8 of them reviewed really well typically averaging between 4.4 and 4.7 stars.

The customer reviews were okay for getting a feel of each model, but they were so inconsistent that there was no way to compare and contrast one model with the next. So one of each was purchased and immediately we began the going over of the models while poking and prodding each one.

Continue reading Best beginner’s auto-ranging Digital Multimeters (DMMs) compared and reviewed

Bathroom Laser Light project — the analog version

A few weeks back, Redditor /u/doakey posted an insanely cool idea to /r/arduino of lighting up his toilet bowl with a red laser so that when he got up in the middle of the night to pee, he could see where he was “shooting”, so to speak. And it was a grand success!

Walk into the bathroom. Laser shoots into the bowl. *pew, pew, pew* Lights up the target like a spotter for some stealth aircraft to hit with a smart bomb. Night vision preserved. Mission accomplished. Laser turns off. Then you go back to bed.


Yet, he noted that the 9v battery only lasted a few days. Naturally, a few of us pointed out that an Arduino is overkill and that he could have done this using analog electronics.

And I get it. Analog is pretty hard. Arduino is relatively easy. There are plenty of resources out there on how to program Arduinos, but analog… well, it is kind of on its way to becoming a “lost art”.

A few people in /r/arduino asked me to write-up my proposed analog verson. After a few weeks of fiddling, here’s the analog circuit (and explanation) I came up with to reproduce the same effects…

Continue reading Bathroom Laser Light project — the analog version

How to Code in Python: A guide for C#/.NET Programmers and Developers (Part 1)

Sometimes being thrown in the proverbial “deep end” is the best way to learn — you’ll either sink or swim. In most cases, you’ll still flail around a lot at first not sure what you’re doing or which way to go.

This post (and hopefully many to follow) will be an on-going observation of learning Python from the perspective of a general Computer Science background with the foundations of an experienced C# programmer/developer.

Continue reading How to Code in Python: A guide for C#/.NET Programmers and Developers (Part 1)

Mini LED USB stick review

“Whoa. What are these?”, I said to myself. And as I looked them over, I realized that what I was holding was essentially just an LED soldered onto a little USB stick. “How useful!”

Mini-LED-USB-sticks-sidesSuch a simple concept with such a multitude of purposes.

  • Plug it into the side of your laptop for some additional light.
  • Attach one to a portable USB battery pack for an emergency flash light.
  • Plug one or two into the side of a USB power outlet for an ad-hoc nightlight.
  • Put one on the end of a USB extension cable and snake it into a hard to light spot.

And the nice part is that you can get a 4 or 5 pack of them for less than $10.

Let’s see how they perform!

Continue reading Mini LED USB stick review

12 Raspberry Pi 2 & 3 model B cases — compared and reviewed

So you’ve got your Raspberry Pi 1 B+ or Raspberry Pi 2 or 3 B model, but you haven’t got a case for it yet. Or maybe you’ve got a case, but you want to “level up” to a nicer one. But which one to get? There are so many!


And it’s true. There are a lot of RPi cases out there. We tried to get our hands on as many Raspberry Pi cases as possible. And here’s our review of 12 cases.

Continue reading 12 Raspberry Pi 2 & 3 model B cases — compared and reviewed

Bluetooth RFID Finders for your iPhone or Android smartphone — compared and reviewed

If you’ve ever lost your keys or your phone, then you know how immensely frustrating such a thing can be. Until recently, the only recourse was to hope that whatever it was that you lost would eventually turn up or that someone would find it and return it to you. Fortunately, there is technology that can help you find your lost item and even proactively prevent you from losing it in the first place. And that technology is known as low-energy RFID (a feature of Bluetooth 4.0.) Where does one get such a technology?


As it turns out, some clever manufacturers have packed this technology up in the form of tags and dongles and made them small enough to attach to your keys or anything else you might possibly lose. There’s a whole bunch of them even! They go by the names “Proximo Tracker”, “Protag Duet”, “LassoTag”, “Tile”, “Stick ‘n’ Find”, “TrackR Wallet”, and even “KeyFinder”.

And the best part is that they sell for around $30.

Continue reading Bluetooth RFID Finders for your iPhone or Android smartphone — compared and reviewed

The Best external HDD for the Nintendo Wii U is a 120GB SSD!

Updated 05/26/2016: If you are one of the 12 million Nintendo Wii U owners out there, chances are that you know how awesome the Wii U truly is. As you may recall with the regular Wii, there were the larger games found on disc and online shopping known as “WiiWare” that you could download. Because this downloadable content was rather small, it didn’t really take up much space on the internal memory system. And if you really needed more storage, there was always the SD card slot. No big deal.

black-n-white-wii-uWith the Wii U, there are two models:

  • The white model with 8GB of internal flash storage
  • The black model with 32GB of internal flash storage

By today’s standards, both sizes are rather paltry. And now that it is possible to download full games directly to the Wii U, it is quite easy to fill up the internal memory. (Xenoblade Chronicles X… Super Smash Brothers… etc…)

What to do… What to do…

Continue reading The Best external HDD for the Nintendo Wii U is a 120GB SSD!

The portable LED USB multimeter (that you didn’t know you needed)

Update 08/01/2016: If you’re looking for full-size multimeters with USB support. There’s a new article on budget DMMs. Of which 2 DMMs have USB data connection support.

The USB port is one of those things in the 21st century that provides the necessary “lifeblood” (electricity) to charge and re-charge all of our fancy cellphones and gadgets. Yet rarely in this process is there a good way to know that things are going well in the power transfer process. Maybe you’ve experienced plugging in your phone to charge and yet for some reason it doesn’t appear to take a charge or perhaps it’s just charging too slowly. And how does one figure out what to do about this? Surely, there is a little gizmo that can help us out here!


And sure enough, there is. In fact, there’s more than just one. There’s a whole bunch of them. They go by the names “charger doctor”, “USB detector”, “USB meter”, and even “USB power monitor”. At the end of the day, they’re mostly just digital multimeters designed for the USB port, but what they do is insightful!

And the best part is that they sell for under $15.

Continue reading The portable LED USB multimeter (that you didn’t know you needed)

Handbrake -vs- RipBot264 — FIGHT!

If you’ve ever had to encode or transcode a video, then you know that it is both time consuming and difficult to get right. And if you have a lot of videos to re-encode, then it can be a massive pain in the neck.

In the A/V community, there are a bunch of popular tools that can do this for you, but the two that stand out the most are Handbrake and RipBot264. Both programs are free, but each offer something the other doesn’t. This article is meant to be a quick “compare and contrast” of the two programs.

Continue reading Handbrake -vs- RipBot264 — FIGHT!