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3.12 How long can I expect my CED VideoDiscs to last?




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This article is from the RCA SelectaVision VideoDisc FAQ, by tom@cedmagic.com (Tom Howe) with numerous contributions by others.

3.12 How long can I expect my CED VideoDiscs to last?

This depends upon whether you're thinking of the number of times a disc
can be played, or the life of the disc sitting on the shelf. RCA
estimated the acceptable life of a disc at 500 plays. The discs don't
fail suddenly, but gradually exhibit increased noise in the audio and
video signals and more frequent skipping. When RCA was demonstrating the
CED system prior to introduction, they would lock the stylus to a single
groove for 20 minutes, and then play back over that section to show the
disc was undamaged. But that doesn't mean the discs can be played 9,000
times (450 RPM x 20 min.), since the demonstration didn't take into
account the wear and tear of loading the disc into the player 9,000
times.

The shelf life of a CED is basically unknown, but I'd make a guess that
it's around a hundred years. Of course, that begs the question of
whether there will be any functional CED stylus cartridges still in
existence to play the discs. Some people might think a hundred year
estimate is awfully long, but consider that vinyl audio records have
been around since the late 1940's, so there are 50 year old vinyl discs
out there that are still playable. The counter argument to this is that
CED grooves are much smaller (38 CED grooves fit inside a single audio
LP groove), so CED's won't last as long. But the CED stylus is
correspondingly smaller and the stylus tracking force is much less

(0.065 grams on CED's vs. 2 grams typically on audio LP's).

To ensure long disc life you should follow RCA's recommendations, i.e.
store the discs vertically in a slightly cool environment of constant
temperature. Subjecting the discs to wide temperature fluctuations,
particularly on a daily basis, could significantly shorten that 100 year
estimate.


 

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previous page: 3.11 Some of my CED's play fine at the beginning and end of a side,
  
page up: RCA SelectaVision VideoDisc FAQ
  
next page: 3.13 Is it true that RCA VideoDiscs will be unplayable once thecoating on the disc surface evaporates?