About
In this post I will document some of my smaller projects that don’t deserve a whole blog post of their own.
Radio Transmitter
Years ago I made this FM radio transmitter. It’s powered by a 9V battery and transmits the audio signal from the 3.5mm audio jack. The frequency is somewhere in the range a regular FM radio can receive.
DIY Mini FPV Camera
I made this DIY mini FPV camera for my racing quadcopter back in the day. Nowadays you can buy these small compact camera/transmitter combos already prebuilt for very cheap so it doesn’t make much sense to make your own.
It’s meant to be powered from the 5V output of the flight controller. The dip switches are used to set the channel of the transmitter. As you can see in the right image the camera produces a nice image. The only problem is that it tends to heat up quite a bit which is why I added a little heatsink at the bottom. However, this isn’t a problem as long as you are flying and there is a constant airflow camera/transmitter.
3D Printed Keycap
When I first got my DLP 3D printer I made a couple of test prints including this Pikachu keycap. I decided to paint the key cap, make a little enclosure for the mechanical keyboard switch, and use a 555 timer to turn on the backlight of the switch for some time. This was a kind of pointless project that I made just for fun.
The circuit is made from a 555 timer in the monostable mode that is powered by 5V from a USB connector.
Controlling a Pneumatic Piston With Arduino

This is a simple Arduino pneumatics controller I made as a test before using it as part of my spot welder project. The Idea here is to use a piston on a spot welder to close its the contacts together on the welding piece, weld the piece and release the contacts again.
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These were some of the smaller projects I made. I probably make some additions to this post in the future …