DIY PC Footswitch Using a Sustain Pedal

A couple of years ago I picked up an inexpensive sustain pedal for an electric piano at a garage sale. The piano itself wasn’t much to look at, but the pedal intrigued me… it’s a basic on/off switch, but the pedal itself feels fairly robust and I thought it would be a handy switch to have around.

This past week I finally got around to doing something with it! I built a small box that converts the signal from the pedal into a keypress, allowing me to use this pedal as a foot-controlled hotkey for my PC.

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Relay Boxes for Controlling 120V Power with a Microcontroller

For one of my recent projects, I needed a way to control some lights powered by a 120V household wall socket. Rather than reverse-engineering some commercial “smart outlets” for the task, I decided to try and do this the old-fashioned way by embedding relays in electrical boxes.

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Time Circuit Display: LED Standoffs

The time circuit display is a mix of three LED types: alphanumeric displays, seven-segment displays, and standalone 3 mm LEDs. Each one has a different height off of the circuit board and a different distance to the faceplate. I need to offset the components so all of the parts mate with the faceplate correctly, which requires sourcing LED standoffs and designing my own custom ones.

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Making a Time Circuit Display Schematic

I’ve chosen the LED displays, found a matrix driver, and determined the final positions for each LED display on the faceplate. The next step in the time circuits project is to build a dedicated circuit board for each display. This process starts with creating an electrical schematic.

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Dimensioning the Time Circuit Display Faceplate

I’ve figured out what LED displays I’m going to use and I’ve found the case they’re going to fit in, but before I can design a custom circuit board I need to figure-out how they’re going to be spaced in the enclosure.
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