this information is wrong- many 8-track decks use AC MOTORS- such as
Akai 80-81-82, Wollensack 8050, some Sony TC-228, most Zenith, all JVC
I've seen, and many more. read the archives on AC motors, the AC motor
decks are the best.

to get an ac motor to turn in the proper direction, and regulate the
speed to 3.75 IPS, they use a capacitor in series with the motor.

your trusted tech is mistaken