[Info-vax] TK50 - this is annoying...

[Bob Koehler]

In article <k5rnkc$7os$1 at Iltempo.Update.UU.SE>, Johnny Billquist <bqt at softjar.se> writes:
> 
> The fastest tapes on a PDP-11 is the TU77, which writes at 125 ips. At 
> 1600 bpi, that means it writes 200,000 bits per second per track, so 
> approx 200 KB/s. And this is disregarding the block gaps, where it will 
> pause.
>
> Are you saying that no disks you had could exceed that?
> 

   We had RM03, I think, and TU45.  Out engineer insisted the TU45
   was faster.
 
> A normal RP05 or RP06 will transfer 806 KB/s, just as comparison.

   What kind of delay do you get when the disk does a seek?  That
   could kill our application.  It was hard real-time, get behind once
   and you failed.

> And both the TU77 and the RP drives hang off massbus, so the speed 
> outside of the drive have the same restrictions, so no way the disk 
> could ever be slower than the tape.

   MASSBUS?  We din't have no stinkin' MASSBUS.  These were UNIBUS
   systems.