Comment by bombcar

As a counter, you can get amazingly far with little to no EE knowledge - depending on your troubleshooting skills and how modular something is.

A stereo that loses the right channel unless you push on the board? Broken solder joint.

Visibly exploded caps? Bad caps.

Some basic understanding of electricity and current flow and the high-level concepts will help, but a detailed education is more for building your own than just repairing existing mass-produced setups.

(As an aside the electrical knowledge in a good ham radio study guide would be a great place to start - https://home.arrl.org/action/Store/Product-Details/productId... )