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Isolating digital buses can help with a lot of different issues. One of the biggest issues is when you want to connect to a circuit that is part of a high-voltage project, e.g., a Tesla coil or even just vacuum tube systems like Nixies. This 4-channel digital isolator (3 out, 1 in) is a well-designed little board that also provides compatibility with both 3.3v and 5V systems.

Having an isolation barrier protects your low-voltage circuitry against transients and differing ground potentials, as well as protecting against high-voltage shorting to a signal pin. It’s much easier to replace an isolator chip than your expensive FPGA or SoC. This board is based around the TI ISOW7841, which is a great choice for this project. It is designed for a working isolation of 1000Vrms with transients of up to 7kV! There are other chips in this line that have differing numbers of in/out channels, as well as different working isolation voltages; they are mostly drop-in compatible (be sure to check the datasheet!).

These can also be used when connecting a USB logic analyzer to a high-voltage system. While you can unplug a laptop to get isolation, sometimes this isn’t feasible, and of course, PCs must be plugged in to work. You can easily damage circuitry if the ground potentials are different and there is no isolation barrier in place — so pick one of these up and keep it in the toolbox! You’ll be glad you have one when the time comes.

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The Acorn Electron was the low-cost sibling to the popular BBC Micro home computer. It was Acorn’s attempt to offer many of the features of the Beeb at a price closer to that of the rock-bottom ZX Spectrum. It has a beloved status and loyal fans, and nothing makes this clearer than the first SD card cartridge being released! The ElkSD-Plus1 SD Card Cartridge is not only a way to access disk files rapidly, but it also includes a RAM expansion to boost the Elk up to 48KB.

It does require the Plus 1 expansion, which added joystick ports, a parallel port, and a cartridge slot for ROM cartridge expansions. However, Ramtop Retro also offer the ElkSD64 for those without a Plus 1, which is awesome. It connects to the expansion port (where the Plus 1 would normally attach) instead of to the cartridge slot on the Plus 1.

Both versions use standard FAT32 formatted SD cards and support standard .SSD format Electron disk images. Officially, it supports up to 8GB cards, but larger cards have been tested and shown to work, although it’s not guaranteed. The ElkSD has very high compatibility with a wide range of games and software.

So if you’ve got an Acorn Electron and want to put all your software onto a single SD card, be sure to check out the ElkSD cartridges!

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We love reverse engineering here at Tindie! The process of examining bits and pieces of data and using experience and logic to understand how something works is both rewarding and fun. Having the correct tools on hand to reverse engineer things can make the job easier – and the very cool Spy! Break! Inject! board from Mike Coats ticks some very important boxes.

First, the PCB design is super cool, with silkscreen “traces” swirling around, over and under each other (don’t worry, it’s just for effect, the actual traces are direct and well-routed). We love the contrasting colours. Second, the inclusion of high-quality Wurth connectors is a very nice touch! You can choose to isolate particular lines by removing jumpers, and you can sniff the bus with multimeter probes, oscilloscope probes, or via standard DuPont style headers.

You can use the board in many different ways. For example, you could have an I2C bus as well as VCC and GND. Or, you could have SPI signals PICO, POCI, CS and GND. The configuration is up to you! If you use this board to do some RE work, be sure to show us on Mastodon!

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AVR chips have been popular for a very long time due to their combination of low price, efficient instruction set, very low power consumption, and flexible peripherals. Before the sale to Microchip, Atmel had started releasing two new series of chips – the ATtiny 0- and 1-series. These low-power chips featured new peripherals and were a great upgrade path from smaller ATtiny chips. If you want to check out the ATtiny1616, a member of the 1-series, the ATtuno is a great choice.

The board comes with Wago connectors for extremely easy wiring of prototypes. Additionally, a 4×4 grid of WS2812 RGB LEDs is included, plus a Stemma QT/Qwiic compatible port for attaching all sorts of peripherals. Switches are included to change the power source between USB and the UPDI programming port, as well as change Vcc between 3.3 and 5V.

There’s also a slightly less expensive version that doesn’t come with the Wago headers; instead, you simply solder in normal 0.1″ headers, which have separate footprints on the board. Multiple LEDs show the status of various functions on the board, like which voltage is selected, whether the UPDI programming pin is being used, plus the classic UART TX/RX LEDs.

All you need to get started is a USB cable! It’s not a bad idea to get your hands on an MPLAB Snap or similar programmer that supports UPDI, as having full debug functionality can be very useful.

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One of our favourite sellers, 8086 Consultancy, is back with another nifty gadget for your Pi Picos! This board attaches to the header pins on the bottom of your Pico and provides a visual indicator of the state of each GPIO pin. Not only does this look neat, but it’s also very handy for debugging. Normal GPIO pins have amber LEDs, but the power pins have red LEDs, which can be very useful – a quick glance will tell you if power is successfully coming through a USB cable, for example.

Each LED is connected via a solder jumper and a resistor, so you can easily disconnect particular pins if needed. The board is available with different header types, including stacking headers, regular headers, or without any headers at all if you want to solder your own. Slap it onto the bottom of your Pico (or Pico W/2/2W/any compatible board) and instantly get an overview of the pins.

8086 Consultancy has a long history of making extremely useful and well-built gadgets and tools for working with Pis, as well as USB and serial devices. This is just another in a long line of very useful products!

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The Mengenlehreuhr, German for “Set Theory Clock”, more commonly known as the Berlin-Uhr clock was the first public clock in the world to use lighted segments to represent the time. It was commissioned by the West German Senate and was a popular photo spot in West Berlin, and in modern Berlin it has been moved to the front of the Europa-Center. If you love the retro-futuristic look of this very unique clock, then make sure you check out this amazing Berlin-Uhr Table Clock!

The kit comes unassembled, and assembly requires both soldering, gluing, and epoxy pouring. If you’ve never poured epoxy resin before, definitely take a look online at some resources or videos of people doing it to get a feel for the process. We particularly like Peter Brown’s channel Shop Time! His lighthearted and creative personality get you wanting to pour epoxy on everything.

The clock works by flashing the top light on and off, once every two seconds. So if the lamp is off, it’s an even second, and if it’s on, it’s an odd second. The eight red rectangles below encode the hour: multiply the number of illuminated boxes in the top row by 5, and then add the number of boxes in the bottom row. The next row, which contains mixed red and yellow rectangles, represents 5-minute increments. The bottom 4 lamps encode individual minutes. So, the displayed time in the image above is: 4*5 = 20 hours, plus 2, for 22h. 6 segments of 5 minutes each = 30, plus 3, so 22:33 is the time, and we’re on an odd second. Pretty neat, especially for a public sculpture in 1974!

The project is fully open source, and is in the process of being certified Open Source Hardware by OSHWA! Be sure to also check out their DCF77 bitstream clock, which appears to be a work in progress. As someone interested in longwave broadcasts and in atomic time transmissions in particular, this one piqued my interest. Perhaps someday we’ll cover that clock, too!

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The Amiga was well known for creative expression; from music to digital art and desktop publishing, it could handle a lot of things that contemporary machines couldn’t. It output video in RGB, which was amazing if you had an RGB monitor, but if you didn’t, you had to purchase a separate TV modulator or composite conversion module. The AMYVIDHYBRID+FBAS is a modern solution that gives crisp, high-quality composite and S-video output, while still allowing use of the RGB outputs and the genlocking capabilities that go with it.

This module not only produces composite and S-video, but it does it in a way that produces much sharper and more vibrant video than the original Commodore-made composite video converter. To use it, you install it in place of the original Commodore Video Hybrid (often called the VIDIOT), which does require desoldering. If you’re not experienced at desoldering ICs, you should ask a hacker buddy for help, especially if they have a vacuum desoldering tool. Use lots of flux, and be careful not to lift traces. Remember, if you use solder wick, dab it on, and don’t drag it across the PCB while pressing with the iron — that’s a recipe for ripping up PCB traces and pads!

Once you’ve got it installed, composite output is available on the hybrid output pins leading to the video connector, and S-video requires soldering a simple RCA socket to the left side of the hybrid and connecting it there. Of course, you could always route the video in any way you want by adding new connectors. You’ll be happy with the boost in picture quality and the flexibility of having multiple video standards on your Miggy!

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During the 1980s, many vendors sold small, pocket-sized computers that ran BASIC. Despite their small size and low power consumption, they were relatively capable and could interface with tape storage and thermal printers. The SHARP PC-1500 was a very popular model with a Z80-based CPU. However, its weak point was the small amount of RAM and storage space for programs – only 2k. Some expansion modules are still found for sale from the period, but they are ridiculously expensive. This 16k RAM Module with Battery Backup is a great way to breathe some new life into these old machines!

Not only does this give a huge upgrade to storage space as NVRAM, but it also uses modern memory chips which are very low-power. This means the CR1616 battery should be able to keep the contents of RAM for a long time. This is useful as the machine uses 4xAA batteries. Ideally, using rechargeable AA batteries should be the goal, but you still need to power down the device to swap batteries; this would lead to the memory being wiped without a secondary power source.

Gold-plated contacts ensure a good connection to the expansion port connector. This module is compatible with all SHARP PC-1500 and PC-1500/A models, as well as the TRS-80 PC-2 model rebadged for sale at Radio Shack. Pick one up and supercharge your classic pocket PC while still enjoying the vintage BASIC programming goodness!

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If you’ve been thinking about developing a wireless device, whether IoT or not, this ARGALI SIM C3 is an absolutely packed development board. It’s in the format of a Feather board, with an ESP32-C3 module plus a SIM7080 modem. So in one board you have wireless radios for Bluetooth/BLE, WiFi, GPS, Thread, Zigbee, Matter, and NB-LTE (CAT-M). This powerful combination of radios allows both low-power, short-range connections to wireless sensors or mesh networks, as well as low to medium-power long-range connections to WiFi and LTE for internet access.

A STEMMA QT connector opens up a huge range of sensors to prototype with, allowing you to easily build and test sensor networks. Additionally, a Li-Ion battery connector with charge control circuitry enables true wireless operation, with charging via USB-C or a separate 5V input. This could be used for energy harvesting, solar, or wired power — all taken care of for you so you can focus on developing your application.

This kit comes with three antennas, pin headers, and a Li-Ion battery (though check to make sure shipping batteries to your country is allowed without hassle). The Feather form factor additionally allows a huge range of FeatherWing add-on boards, both from suppliers like Adafruit as well as third-party developers — here on Tindie we have a great selection to check out!

If you’re looking to prototype or deploy an IoT or wireless device that leverages multiple radio stacks plus location data, the ARGALI SIM C3 looks like an awesome choice for quickly getting up to speed.

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Liquid pumps are always fun to play with. Whether you’re automating your garden watering or making a bartending robot, pumps and motors are useful devices. Peristaltic pumps are a special kind of liquid pump in which the fluid does not come into contact with any part of the pump mechanism, only the inside of the tubing. This makes them very useful for beverages or scientific reagents and chemicals. But sometimes you need very precise amounts! I didn’t even know you could get peristaltic pumps this small, but this Tiny Peristaltic Fluid Pump Breakout packs everything you need to carefully dispense small amounts of fluid onto a single board!

The board uses a DRV8833 motor driver IC along with a tiny micro-stepper motor to actuate the pump mechanism. This makes it compatible with popular software libraries for stepper motors, such as Arduino’s Stepper. It has a fault output, which is handy for monitoring and making sure the pump is functioning. It can even support up to 4A of drive current peak, with an average of 3A RMS, which is a lot of oomph for such a small motor.

You can use this for measuring out precise amounts of reagents for doing chemical reactions measuring out small amounts of artificial flavour concentrates for making food or drink, or even tiny amounts of paint for… whatever you want! Check out the video below to see it in action.

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