[Mike Rivers]

On Aug 7, 5:55 pm, wrote:

How do you know how to adjust the azimuth - or how would a device know
what the correct setting is? Is there some fail safe way to tell, or
do you have to use your own ears?

You got it! On the bench, you can use a test cassette and an
oscilloscope but when ajusting the deck to match an already recorded
tape, your ears are the best guide. It's pretty apparent when you have
it right, or at least close enough. For routine transfers just for
fun, you can probalby get away with adjusting it once, but to to a
really good job, you need to listen continuously and when you hear it
getting off, stop the tape, stop the recording, re-adjust the azimuth,
continue the copying, and then edit the pieces together.

The automatic adjustment looks at phase difference between the
channels and drives a motor which adjusts the head.