RE: arsclist Umatic Video Cassettes

["Copeland, Peter" <Peter.Copeland@xxxxx>]

Dear Harry,
    Yes, I've experienced this as well, and with other makes known to give
the same problems on their audio tapes.
    My first procedure must be to ask if the material is accessible anywhere
else. Constant high temperatures *may* considerably weaken the luminance
carrier level.
    Next, if a replacement is not available, use reduced temperature and
increased time - rather than the other way round! For Umatics, I would start
at 40 Celsius, but give them something between ten and twelve hours to allow
the volatiles to escape; and I prop the videocassette door open with a piece
of bent wire for the same reason.
    If it was *still* then sticky, I'd move up to 45 Celsius.
    Et cetra.
    The luminance carrier level was often not visibly worse when you looked
at the complete picture on a monitor; but the usual tweeks with tracking and
skew controls, and an oscilloscope measuring the output of the luminance
carrier-amplifier, are always advisable. In one case, I had worse dropouts
than I had remembered; but I cannot say this was a rigorous "before and
after" comparison.
Peter Copeland 

-----Original Message-----
From: Harry Rice [mailto:Harry_Rice@xxxxxxxxx]
Sent: 03 May 2002 12:23
To: ARSCLIST@xxxxxxxxxxxxxxxx
Subject: arsclist Umatic Video Cassettes


With some Ampex 279 Umatic video cassettes dating from the late 1980s and
early 1990s I am experiencing something like the sticky shed associated with
audio tape.  Is this something that's pretty well documented?  Is baking a
likely solution?

Harry Rice
Berea College


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