On Fri, 04 Jun 2010 13:07:28 +0000, GregS ǝʇoɹʍ:

In article , Meat Plow
wrote:
On Thu, 03 Jun 2010 20:05:21 +0000, GregS ǝʇoɹʍ:

n article , "William R.
Walsh" m wrote:
Hello all...

I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd
like to get the turntable going again. (Despite the source, it's a
pretty nice stereo system...the radio tuner works well, it seems to
have about a 40Wx2 output power rating (which seems reasonable, having
looked at the internals), the cassette deck is a partial logic design
with the ability to skip ahead 1, 2 or 3 songs and the turntable
itself is a linear tracking type.)

Anyway, before I stored it, the turntable was in need of a new belt. I
set the belt aside and now it seems to be gone. I could have sworn
that I read about how to determine an unknown belt size in the FAQ,
but I could not find it just now. As best I remember, a string was
used and placed around all the components driven by the belt, after
which a measurement was taken.

A turntable belt has a lot of stretch to it.

Depends on the individual TT. I've seen belts made of rubberized fabric
that didn't stretch at all. My old Rek-O-Kut TT had a belt that would
not stretcch at all made of some woven vulcanized rubber stuff. Any TT
with a heavy platter like the Rek-O is likely to have a stiff belt. Some
of the el-cheepo tables with aluminum platter will likely have a more
stretchy belt but it's not etched in stone.

The whole idea is isolation. All mine had loose belts. My best Thorens
TD-125 was stretchy. Had a SME arm to install on it, but sold them both.

greg

Loose and stretchy are different things. The belt on the Rek-O was loose
too and I agree that isolation from the drive is a good idea. A stretchy
belt, with more stretch than what is designed, is not good for speed
stability or drift.