It's funny to hear people say that they don't know if they can use a knee lever that many of these old electric machines in cabinets have.
I was raised using a knee lever and LOVE it! In fact, when I had a knee lift on Bernina, I NEVER used it because I couldn't get used to it's function. When I pushed on a knee lever I expected my machine to start sewing...not lift the presser foot! LOL