16 Jun
2015
16 Jun
'15
12:48 p.m.
Johnny Billquist wrote:
Then you can figure out tape speed across the
heads (if you care) by just observing flux changes.
Tony Duell wrote:
Only if there is something on the tape. These computer
tape drives could surely record on a
totally blank tape and get the right number of bits per inch. So the thing can't use
the data rate
at the head as a speed measurement.
Not for something that can write a blank tape (e.g. a 7-track or
9-track), but there were other tape systems that required a formatted
tape, and servoed the reel motors to the flux transition rate.
Obviously the factory had to use a drive with a different tape speed
control system to format the tape.