I have been following a series of podcasts from ‘Chatting with the Designers’ CWTD.ORG that cover building simple Arduino based test equipment. I decided that this would make a nice way to get into development with the ESP32. The CWTD ‘Test Gadget’ is basically an Arduino Nano with a 2 line LCD display, and a breadboard area where small modules can be plugged in to make different types of instruments. My version will use the ESP32 and the TFT display. I am also replacing their rotary encoder with a joystick for the user interface device. I am bringing all the pins from the ESP32 module out to two pairs of female headers, that should allow me to plug in two small modules at the same time.
After building the “awesomely impractical” giant three-key keyboard, I decided it was time to build something a bit more practical—presenting the single ESC key USB keyboard! This keyboard has exactly one function which is to provide an optimal ESCing experience regardless of whatever keyboard you normally use. In exchange for giving up a USB port, you get a dedicated tactile, clicky Cherry MX blue ESC key.
How little do you need for a game
An exercise in futility. That is what many would call this endeavor. How few elements (signifiers and affordances) do you need to not only recognize a game for what it is, but also are able to play it?
It turns out that you only need very little to do very much.
This DIY project will combine the estimated time of arrival function with a Nixie tube display to create an estimated time of arrival (ETA) Nixie tube clock. It is all easily controlled by a Raspberry Pi Zero W that is connected to the internet through WiFi to provide the latest time and gets the ETA for any number of destinations. The travel time is provided by the free Google Directions API interface that includes traffic to give the best estimates on any particular day. The goal is that with an ETA Nixie tube clock, no math is needed to add a rough, often optimistic travel time, to the actual time to determine if we are running late. The clock does that for you and with the power of IOT, is much more accurate! A motion sensor is also added to the clock to turn off the Nixie Tube Display when no one is around, saving power and increasing the Nixie tube lifetime.
Dave Richards (a.k.a. AA7EE) has a nice write-up about building another Si5351 VFO project:
To many, this will be just another Si5351 VFO project, with nothing to distinguish it from the others. In fact, that’s exactly what it is. The “how to” of connecting an Arduino board to an Si5351 board, wiring up a display, and loading the firmware, is straightforward, and well established. To me though, it was a complete mystery.
Matt Brailsford (aka Circuitbeard) has a nice write-up about building his mini pinball machine with a lattepanda core running dual monitors:
I generally start my projects by thinking about the hardware that I’m going to want to use as I’ll need to know sizes when it comes to the design phase. My first thought was to go with a Rasberry Pi as it’s what I’m familiar with and it’s what I’ve used for my other arcades, but after looking online, there really didn’t seem to be any good options for pinball emulation on Linux at all. It all seemed to be windows based. Thankfully I remembered reading about a single board Windows computer called a LattePanda so I thought why not give that a go and so this was the approach I ended up taking.
The NickelBot is complete and it works great. The goal of the project was to create an easily portable machine that creates low cost items that could be given away at events like Maker Faires. I think it has completely achieved that goal. The nickels are purchased from Amazon and cost about $0.08 each.
The generators I am using are in fact geared DC motors, left over from a project with my sponsor RS Components. The modern abacuses being powered during my experiments are a Raspberry Pi Model, a SIMATIC IOT2020 and an Arduino Uno. A 2×16 characters LCD is used to display results. Two geared DC motors are on my board with the test setup
Luke writes, “A few years back I made a compact bench PSU based on a DPS-3002 module and a 24v PSU. I have since made a improved version that also includes the ability to run on my power tool batteries making it ultra-portable.”
Thinking about what values I would like to display, I came up with three basic items. A S-meter when in receive, and a power output display when in transmit. In transmit, I would also like to have the capability of measuring VSWR. Thinking about the switching functions required for this I will need one control line that monitors transmit/receive, this can come from the PTT or key line in the transceiver. Then I use a second control line to select either power or VSWR when the T/R line is in transmit. Another control line can do the same for the S-meter or some other display when in receive. Since this is based on a VU meter, I will use that for the secondary function in receive. Now looking at the signal lines I need to measure, they are the AGC line for S-meter, audio signal for VU meter. And in transmit, the forward and reverse power levels will take care of power and a computed VSWR reading.