I have an Audio technica AT-650 SUT which I bought NOS a couple of years ago but it must be easily 20 years old or more. It is the one with 4 adjustable positions 3, 20, 40 ohms and PASS. Apart from cleaning up the external contacts, might it be worthwhile opening it up and blowing out the cobwebs and spraying the insides and perhaps the switch mechanism with whatever or is it a question of "if it ain't broke, don't touch it".
Do transformers "lose their balls" or are they eternal ?
Do transformers "lose their balls" or are they eternal ?