[Jim Pytel] has a lot of very good instructional videos on his channel, and he recently added one you’ll enjoy on transformers. You probably know that transformers convert one AC voltage into another AC voltage. Some step up voltage, some step down voltage, and others simply pass voltage through but isolate the input from the output.
The 40 minute video covers basics including how the transformer works, the meaning of the turns ratio, and how transformers reflect impedance. You probably should understand how to compute AC power, but if you need a refresher [Jim] has a video for that, too.
The video focuses mostly on power transformers, but many of the same concepts apply to signal transformers, too. We’ve always thought it is interesting that a transformer is just a generator where the rotating magnetic field is generated electrically instead of through shaft rotation. Or, if you prefer, a generator is just a transformer with a rotating magnet replacing the primary.
[Jim] promises to cover non-ideal transformers in a later video, but for this one, the transformers are ideal. That means the power output is the same as the power input, which would be nice, but isn’t realistic. Real transformers lose some power due to a variety of factors and there’s a lot of science behind coil winding and core material to minimize those losses to the extent practical.