> On Jun 16, 2015, at 12:10 PM, tony duell <a...@p850ug1.demon.co.uk> wrote: > >> >> 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.
Another solution is to avoid the problem entirely by not requiring constant linear speed. That’s what DECtape (the real one) does. > > 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