CED VideoDisc and Player Discussion

[cedmagic]

RCA VideoDisc Vice President Dick Sonnenfeldt had a U-matic tape cartridge in his archives which contains a 36-minute demonstration of the CED system conducted on February 5, 1979. He kindly had this transferred off the tape for sharing with the CED community, and it may be viewed via this link:

http://video.google.com/videoplay?docid=-321781081379889657

The gentleman conducting the interview is Financial Times Technology Editor John Chittock. This demonstration was a month after RCA Chairman Edgar Griffiths made his abrupt decision to bring the CED system to market. The interview starts out explaining RCA's initial effort at metallized VideoDiscs and moves on to demonstrate caddy-housed discs using the SDT200 player. Near the end of the interview a much smaller prototype player is shown, which two years later became the production SFT100 CED player. The compact prototype is the same as the model covered in this Featured CED Patent:

http://www.cedmagic.com/museum/ced-patents/4227699-patent.html

--Tom Howe

[k8fan]

I put up a video from 1980 of a report on ABC's 20/20 on the coming videodisc revolution. It features both CED and LD, and has a demonstration of both systems.

Part 1

Part 2

[Jesse Skeen]

Wow- glad someone had the foresight to tape that. Funny how you can see the laser rot on that Elton John laserdisc; I don't think there's a single good copy of that disc in existance.
_________________
Videodisc and stereo sound- there's no better value around!

[Reinhart]

I wouldn't call the problem with the Elton John disc laser rot, per se. Rather, I would attribute that to the simple fact that LaserDiscs were a product that couldn't be manufactured properly until Pioneer came in and fixed it.

Laser rot is characterized not only as speckle video noise, but noise that gets worse over time. The disc in question would have this particular problem right when it came out of the factory at Carson, California.

The fact is that LaserDiscs required clean-room conditions to properly make them. The problem was that MCA failed to recognize this requirement and made discs in a totally unacceptable environment where contamination from dust and other particulates could easily find their way in the discs or between the disc halves. And, of course, the manufacturing process wasn't really perfected on top of this. The result were LaserDiscs that had an appalling defect rate where the majority of the yield was unacceptable while those that passed just did so barely. This also resulted in an increase in price since so many yields were rejected by quality control, which affected the profitability of making LaserDisc software product. It also didn't help that Philips made players that weren't exactly up to snuff in playing these discs, or any disc for that matter. Again, it wasn't until Pioneer started getting involved where LaserDisc improved for the better, although it remained a niche.

I recall an anecdote where Pioneer were churning out test pressings at their Kofu facility while DiscoVision engineers paid a visit. The DiscoVision techs sort of poked fun at Pioneer for taking such "drastic" measures ... that is until Pioneer demonstrated their product to the chagrined DiscoVision staff.

Of course, Pioneer Japan had problems with rotting. But, this particular problem was caused not by a problem in the manufacturing environment but by an improper adhesive compound used to bond the two disc halves together. Once this was rectified, the rotting problem was mostly eliminated, although it did pop up from time to time from manufacturer to manufacturer. And, there are also some defects that occur due to a slip up, such as improper timing of the injection molding, which causes cone warpage. But, in its defense, LaserDisc has a better defect rate than pre-recorded video cassettes.

Although, I would have to say that, ultimately, CED perhaps has a superior defect rate to LaserDisc since it is a simpler product to manufacture. Problems with CED typically are due to wear, mostly from the loading and unloading of the disc and far less from actual playback. - Reinhart