[pjposterguy]

Originally Posted by GRC

You sound as though you want to harm the tape.

If you remove the power cable while the deck is running in play or record mode, and leave it that way for a while, the pressure between the capstan and pinch roller, where they grip the tape, will eventually deform the pinch roller, and leave an indentation in the tape. Short answer is 'don't do this'.

Removing an audio cable whilst the deck is running will not damage the tape in any way.

If you move the deck sharply enough, it's unlikely, but you could derail things enough to cause physical damage to the tape, but you'd really have to try hard to do so, I think. Again, the short answer is 'don't do this'

Does this help?

noob to this website says WOW people know what a capstan and pinchroller are
@OP the numbers refer to a noise reduction format (MOST likely dolby) by playing a cassette in the wrong format should not physically harm it.... it'll just screw with the spectra/EQ.... as for squeaking, it SEEMS like a physical problem with the tape deck.....

as for unplugging stuff.... NEVER!!!! I, at least have WAY too much money invested in my gear to potentially destroy it... ALWAYS power up/down your gear in the correct sequence