Archive of the former Yahoo!Groups mailing list: The Mellotron Group

If any one is familiar with Roberts tape recorders, or Akai if not
stateside, models 990, 997, and early 720 were half track capable
machines. A rotary switch on the heads gave you choices of 1/4 track
left-stereo-right in 1/4 track mode and 2 track stere, or half track.
These were introduced in 1962 and are tube (valve) driven. All machines
had speeds of 3 3/4, 7 1/2, and 15 i.p.s. and although s/n and wow and
flutter charachteristics were not as good as later machines, they were
very impressive in their time. One feature these machines included was
switchable bias for recording speeds, basically a treble roll off for
higher speed. These were institutional work horses in their day and
even today, I can still get belts, idlers, tubes, and still use mine
quite a bit. Doug