What would be
an example of a different setup?
F'rinstance, there were cassette replacements made for paper tape gear,
which recorded NRZ data digitally on a cassette tape. These things usually
had extra functionality, such as high-speed search. In these, a steady
tape velocity isn't particularly important, unlike an audio recorder.
Indeed. All audio cassette recorders use a capstan and pinch roller drive
to maintain constant tape speed. Many digital cassette drives don't --
they just drive the tape spools. The HP9830 is certainly of the latter type.
-tony