16 Jun
2015
16 Jun
'15
12:31 p.m.
On Jun 16, 2015, at 3:20 PM, tony duell <ard at
p850ug1.demon.co.uk> wrote:
...
Most don?t. Some do. I remember using IBM tape drives on a 360 Model 44 that were
amazingly badly designed.
Part 1: two capstans spinning all the time, in opposite directions. Solenoid-activated
pinch rollers would press the tape against the capstan to set it moving. The same
solenoid-activated pinch roller moved in the opposite direction would press the tape
against a non-moving ?capstan" to stop it.
Part 2: vacuum columns ? no surprise there. But why on earth would anyone build a vacuum
column that has the oxide side of the tape facing OUTward, rubbing the oxide against the
column side walls?
Amazingly enough, those drives did work reasonably reliably, but I would never want such a
beast in my shop.
paul
The actual tape movement as such, is all done by
the small wheel next to
the head, which just runs the tape past the head.
Which is essentailly the same as the capstan in an audio tape recorder, albeit the
computer
drive doesn't have a pinch roller