So I had a flash of inspiration last week. I love vintage sewing machines, what I don't love is the way the foot pedals work. They're mechanical and usually use carbon or wire wrapped resistors that don't provide consistent power through the travel of the pedal. Excess power that doesn't go to the motor is turned into heat making the pedal hot when you sew slowly. The old ones are always out of adjustment and wear out depending on how much they were used.
I found a used electronic foot pedal at the thrift shop for a few bucks. All I did was cut my mechanical pedal off and splice the electronic one on. This is very easy stuff to do with a wire cutter and some electrical tape. The worse thing you'll likely get if you do it wrong is a sewing machine that runs at full speed without your pressing the pedal. Please take proper safety measures if you do this, unplug the machine first from the wall outlet. The electronic pedal uses a circuit that gives even power through the travel of the pedal and does not generate heat. My old vintage sewing machine is much more precise now with this cheap and easy upgrade.
You must use an electronic pedal that was designed to be used with a mechanical sewing machine, the gauge of the wire will be thick like the one you're cutting off your machine. A pedal for a computerized sewing machine won't work, it will have much smaller gauge wire. This is very easy, but any electrical work is obviously at your own risk.
Here's a YouTube video where I talk on this subject: