16 Jun
2015
16 Jun
'15
9:21 a.m.
On Jun 16, 2015, at 12:10 PM, tony duell <ard at
p850ug1.demon.co.uk> wrote:
Another solution is to avoid the problem entirely by not requiring constant linear speed.
That?s what DECtape (the real one) does.
As long as we're talking philosophy, what do y'all think about emulating the TU58
drive, vs. emulating the TU58 > *tape*?
I cannot properly express my opinion of that tape cartridge design even if I violate list
rules about use of
profanity. But the drive itself isn't all that bad, aside from not having enough
motors to manipulate a
well-designed tape cartridge mechanism.
The tape cartridge (along with QIC cartridges, etc) is an interesting design. Of course
the general problem is
to run the tape at constant linear speed past the head while winding it off one reel onto
the other. In general
there have been 3 solutions to this.
One is to drive the tape itself using a capstan and maybe a pinch roller. Then have the
takeup spool
driven too fast with a slipping clutch in-line. And a weak brake on the supply spool.
This of course is what
was done in audio recorders (reel to reel and cassette), Video recorders (ditto), etc.
Or a variant: drive the takeup reel with a controlled torque motor and no slip clutch. I
think professional grade tape decks may have been built that way.
paul