On Sat, 17 Dec 2005 10:30:35 -0500, "mc"
wrote:

Many higher end cassette decks use low torque drives as a means of
lowering the wow and flutter specs.
The manufacturers intention was that only high quality cassette
should be used. i.e. ones with only the lowest friction ratings.
I have and older Nakamichi and a top end Akai that are like this and
are particular as hell about the quality of cassettes run in them.
I usually had best results with Denon tapes or the pro stuff put out
by Loranger industries. Both had high quality bearing mechanisms in
the cassette hubs as well as really good graphite pads in the shells.
If you eliminate the tape drive as the problem take a look at the
condition of the cassettes.(Use the sharpened end of a regular pencil
inserted into the drive hubs of the cassette. If any drag is felt when
rotating the pencil you'll need to replace the graphite pads in the
shell.)

Just what I was saying... New cassettes work fine. I am trying to play some
older cassettes in order to transcribe them to other media. I'll follow up
the other fellow's suggestion that the pinch roller pressure may be
insufficient. I'll also see what triggers the auto-stop and whether
something is making it stop prematurely.

You can usually repair a dragging cassette tape by swapping out the
tape spools into a newer cassette shell with good graphite pads and
that'll solve the problem.
Just buy some name brand low bias tapes on sale at your local wal mart
and swap out the spools. You can always swap them back after you get a
decent copy off the old tape.
I've had luck using a light silicone oil swabbed onto the the tape
spools and facing surfaces inside the cassette shell just to get them
to run smoothly for a play or two. Don't overdo the oil though, if it
gets on the tape it's a mess to clean off you tape heads as well as
the tape.( I've got two or three bottles of pure high grade silicone
oil used for the shock absorbers on RC cars that works great for this.
It tends to stick to whatever surface you apply it to and really does
a good job at reducing surface tension)
Just wet the q-tip and rub it on the inside shells and the white
plastic tape hubs and reassemble.
Another problem might be the tape itself. It could have with age
become oily resulting in loss of friction with the drive roller.
Clean your finger tips with denatured alchohol to get off any skin
oils and rub a section of the tape lightly between forefinger and
thumb. If it feels the least bit slippery it's started extruding oils
out of the tape and/or has aqquired a layer of dirt buildup from age.
If so you'll need to clean the tape as well.(I've used denatured
alchohol when I couldn't find a tape cleaning solution. Cotton medical
pads soaked in alchohol will do the trick. You may want to rig up a
set of spindles and a hand crank to make the job bearable.)
There are also services in most cities that'll clean them for you.