On the Emulation of TU58s

Eric Smith spacewar at gmail.com
Tue Jun 16 14:48:09 CDT 2015

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.

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