[Marko] styles himself as a crazy chemist. His video showing a fast tin plating solution for PCBs (YouTube, see below) doesn’t seem so crazy. We will admit, though, it uses some things that you might have to search for.
The formula calls for stannous chloride — you could probably make this by dissolving tin in hydrochloric acid. There’s also thiourea — the main chemical in silver-cleaning dips like Tarn-X. Sulphuric acid and deionized water round out the recipe.
A quick check of the usual Chinese websites will yield USB microscopes for a very low price. However, many of these are little more than webcams with some cheap optics. Not that they can’t be useful, but they probably won’t compete with an expensive instrument like a Dino-Lite. [Shahriar] looks at the latest offerings from Dino-Lite and shows how they can be useful when examining electronics. You can see the video below, but be warned: these little microscopes are not cheap. The entry-level model starts at about $100 and they go up — way up — from there.
Still, many of us spend as much or more on necessary gear and these days a microscope for inspecting tiny circuits is pretty handy. In addition to the optical instruments, [Shahriar] also looks at a stepper motor-driven microscope stage, which is interesting.
It wasn’t long ago that you needed to know Morse code to be a ham radio operator. That requirement has gone in most places, but code is still useful and many hams use it, especially hams that like to hack. Now, hams are using the Raspberry Pi to receive highly readable Morse code using very low power. The software is QrssPiG and it can process audio or use a cheap SDR dongle.
There are a few reasons code performs better than voice and many other modes. First, building transmitters for Morse is very simple. In addition, Morse code is highly readable, even under poor conditions. This is partly because it is extremely narrow bandwidth and partly because your brain is an amazing signal processor.
Like most communication methods, the slower you go the easier it is to get a signal through. In ham radio parlance, QRS means “send slower”, so QRSS has come to mean mean “send very slowly”. So hams are using very slow code, and listening for it using computerized methods. Because the data rate is so slow, the computer has time to do extreme methods to recover the signal — essentially, it can employ an extremely narrow filter. Having a QRSS signal detected around the world from a transmitter running much less than a watt is quite common. You can see a video introduction to the mode from [K6BFA] and [KI4WKZ], below.
If you fly much or work in a loud office, you know that noise-canceling headphones can be a sanity saver. Wouldn’t it be nice if you could just have noise-canceling without the headphones? Apparently, a lot of people think that’s a good idea and funded a project called Muzo. [Electroboom] borrowed one and — mystified how such a device could work — set out to test it. Along the way, in the video below, you can see him do a neat demonstration with two speakers canceling each other in his closet.
Based on [Electroboom’s] tests and the tests from other users, it doesn’t appear that Muzo does much to reduce noise. It might add some noise of its own, but that’s a far cry from what people expected the unit to do.
Continue reading “The Sounds Of Silence? Muzo Fails To Deliver”
We’ve talked about TensorFlow before — Google’s deep learning library. Crunching all that data is the province of big computers, not embedded systems, right? Not so fast. [Neil-Tan] and others have been working on uTensor, an implementation that runs on boards that support Mbed-OS 5.6 or higher.
Mbed of course is the embedded framework for ARM, and uTensor requires at least 256K of RAM on the chip and an SD card less than (that’s right; less than) 32 GB. If your board of choice doesn’t already have an SD card slot, you’ll need to add one.
Continue reading “Tiny Tensor Brings Machine Deep Learning To Micros”
If you have an Alexa, one of the best things you can buy to go with it is a Harmony Hub remote. Sure, you get a universal remote to control all your home theater equipment, but you’ll hardly use it because the Alexa can virtually push the Harmony buttons for you. The negative word in this paragraph, though, is “buy.” The Harmony Hub isn’t inexpensive. Fortunately [Michael Higginis] has you covered. He has an ESP8266 universal remote that you can control with Alexa. You can see a video of setting the system up below.
On the one hand, the idea is fairly simple. An ESP8266 has plenty of horsepower to read and recreate IR codes. However, we were very impressed with the web portal used to configure the device and integrating it with Alexa is a neat trick.
[Mitch] got interested in the S8 “data line locator” so he did the work to tear into its hardware and software. If you haven’t seen these, they appear to be a USB cable. However, inside the USB plug is a small GSM radio that allows you to query the device for its location, listen on a tiny microphone, or even have it call you back when it hears something. The idea is that you plug the cable into your car charger and a thief would never know it was a tracking device. Of course, you can probably think of less savory uses despite the warning on Banggood:
Please strictly abide by the relevant laws of the state, shall not be used for any illegal use of this product, the consequences of the use of self conceit.
We aren’t sure what the last part means, but we are pretty sure people can and will use these for no good, so it is interesting to see what they contain.
