Weekly Classic Computer Trivia Question (20141205)

[Jerome H. Fine]

 >tony duell wrote:

>>Approximately how many DECtapes will fit on a single one terabyte drive?
>>
>All that were ever made?
>
If I remember correctly, a TU-58 tape holds 512 blocks of 512 bytes
or 262,144 bytes in total or 2 ** 18 bytes

Assuming that 1 terabyte is 2 ** 40 bytes, each drive could hold
2 ** 22 tapes or 4 million tapes.  Please correct my arithmetic if
I made any mistakes.  Depending on the over capacity specified
by the manufacturer of a hard drive (usually unformatted capacity),
a terabyte drive should still be able to hold at least 3 million tapes.

I don't have any production figures from DEC for TU-58 tapes,
but 3 million could certainly be a good order of magnitude estimate
for the total production.

Jerome Fine