16 Jun
2015
16 Jun
'15
10:44 a.m.
[Driving tape]
They were. Or at least some semi-professional audio recorders were built like that. The
Revox G36 (736) and Brennell Mk 5 among them (I happen to have both). Actually, the
Philips V2000 video recorders (home machines,
not professional but quite the best of the home systems) did that. They had a pair of DC
motors to directly
drive the 2 spools along with the capstan and head drum motors. No slipping clutches. Back
tension was
provided not by a light brake on the supply spool but by a suitable current through the
supply spool motor
in those machines.
-tony
Another solution is to avoid the problem entirely by
not requiring constant linear speed. That?s what DECtape
(the real one) does.
Sure. A number of tape drives were built that way, the HP9865 (and thus the built-in tape
drive on the
HP9830) is another example.
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.