This is a video demonstrating a DIY foot-drum I made for myself. The heart of it is an old tambourine. A used mounting bracket from a ceiling vent fan makes the A-frame stand. It's attached to an old board. The pedal is some mdf flooring offcuts I nailed together. I used a bit of trim from the kitchen to make a fulcrum. There is small bit of block attached to the top of the a-frame that I drilled a hole through for the eye-bolt and wingnut that attaches the tambourine. The trick is to wedge this block to the correct striking angle for the pedal. I put a it of spring below the pedal to soften the return.
Since I made this vid, I've further tapered the beater, and wrapped the end in leather. It makes a HUGE difference in the sound. You get a more bassy sound with the wrapped beater.