Capacitance Electronic Disc

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Capacitance Electronic Discs

The CED disc, exposed from protective caddy
Media type:	video playback media
Capacity:	60 minutes NTSC video per side, 27,000 frames per side[1]
Usage:	video playback

The Capacitance Electronic Disc (or CED) was a video playback system developed by RCA, in which video and audio could be played back on a TV using a special analog needle and high-density groove system similar to phonograph records.

Introduced in 1981, the CED system was widely seen as a technological success which was able to increase the density of a long playing record by two orders of magnitude.^[2] However, the CED system fell victim to poor planning, conflicts within RCA, and technical difficulties that stalled production of the system until 1981. Sales for the system were nowhere within projected estimates, and by 1986, RCA had discontinued the project, losing an estimated $60 million in the process.

The format was commonly known as "videodisc", leading to much confusion with Laserdisc format, which is mutually incompatible with this format.

The name "SelectaVision" was RCA's brand name for the CED system. It was also used for some early RCA brand VCRs,^[3] and other experimental projects at RCA.^[4][5]

Contents 1 History 1.1 Beginnings and Release 1.2 Demise 2 How CEDs worked 3 Advantages of CEDs 4 Disadvantages of CEDs 5 Available CED Material 5.1 Hardware 5.2 Software 6 Milestones 7 See also 8 Resources 9 References 10 External links

[edit] History

[edit] Beginnings and Release

RCA began videodisc research in 1964, in an attempt to produce a phonograph-like method of reproducing video. Research was slow in the early years of research and development, as the development team was originally comprised of only four men,^[6] but by 1972, the CED team at RCA had produced a disc capable of holding ten minutes of color video (a portion of an episode of Get Smart).^[7]

The first CED prototype discs were multi-layered, implementing a nickel substrate within the platter. However, premature failure of the multilayer discs, usually from separation of the layers and resulting in damage to the player if a disc in such condition was played, forced RCA to search for solutions to the problem or alternative materials to crafting the disc.^[8] The final disc would be crafted using PVC blended with carbon to allow the disc to be conductive. To preserve stylus and groove life, a thin layer of silicone was applied to the disc as a lubricant. ^[9]

CED videodiscs were originally meant to be handled by hand. But, during testing, it was shown that people could accidentally touch the signal surface of the disc, causing signal degradation on the affected area. Thus, an idea was developed in which the disc would be stored in a caddy from which the CED would be extracted.^[10]

After seventeen years of research and development, the first CED player (the SFT100W) was released in March 1981. A catalog of approximately 50 titles was released at the same time.^[11] Fifteen months later, RCA released the SGT200 and SGT250 players, both with stereo sound. Models with remote controls and random access hit the market in spring and fall, 1983, respectively.

[edit] Demise

Several problems doomed the new CED system, almost from the start. From an early point in the development of the CED system, it was clear that VCRs and home videotape - with their longer storage capacity and recording abilities - would pose a threat to the CED system.^[12] However, development pushed ahead; to dispose of all the work done at RCA would have cost the company millions of dollars. Once finally released, sales for the new CED system were slow; RCA had expected to sell 200,000 players by the beginning of 1982, but only 100,000 had been sold, and throughout 1982 and '83, sales did not improve much.^[2][13]

"...Machiavelli noted that '..there is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things...' At videodisc, I believe these words had special significance..."

Dr. Jay J. Brandinger, Vice President, RCA SelectaVision Videodisc Operations, June 27, 1986.[14]

The long period of development - caused in part by political turmoil and a great deal of turnover in the high command of RCA - also contributed to the demise of the CED system. RCA had originally slated the videodisc system for a 1977 release. However, the discs were still not able to hold more than thirty minutes of video per side, and the nickel-like material used by RCA to make discs was not sturdy enough to put into manufacturing. Signal degradation was also an issue, as the handling of the discs was causing the discs to deteriorate more rapidly than expected, leaving engineers baffled.

RCA had hoped that by 1991 CED players would be in close to 50% of American homes,^[2] but the sales of players continued to drop. RCA attempted to cut the prices of CED players and offer special incentives to consumers, but sales did not recover, and by 1984, executives realized that the system would not be as successful as projected and cancelled production of CED players.^[13] In a strange twist, sales of the videodiscs themselves were twice the projected rate, so RCA announced that videodiscs would be produced for at least another three years after the discontinuation of players. After this announcement, the sale of discs declined severely, causing RCA to abandon disc production after only two years.^[15] The last titles released were The Jewel of the Nile by CBS/Fox Video,^[16] and Memories of VideoDisc, a commemorative CED given to many RCA employees involved with the CED project,^[17] both in 1986.

[edit] How CEDs worked

CEDs were 12 inch (305 mm) conductive vinyl platters. The video and audio signals were stored on the Videodiscs via peaks and valleys in the grooves, similar to a phonograph record, of both sides of the discs. A keel-shaped needle with a titanium electrode layer would ride in the groove with extremely light tracking force, reading the electrical signal from the groove where it is decoded from an FM state into video and audio signals.

Unlike a phonograph record, where physical movement (vibration) of the stylus in the groove of the platter led to an audio signal, the stylus in a CED player slid along the crests of the groove at a constant rotational speed of 450 rpm. The varying undulations of the peaks and valleys in the groove provided differing amounts of capacitance between the stylus and the conductive carbon- loaded PVC disc. This varying capacitance was measured by the player circuitry, providing an audio/video signal.

Also unlike a phonograph record (and more like a floppy disk), the grooves on a CED do not consist of a single groove in a spiral, but of concentric grooves, each containing a fixed amount of audio/video time (for interlaced video: 8 fields, or 4 complete frames—2/15 of a second).

The disc is stored inside a caddy. On the inner edges of the outlet of the caddy, there are felt strips designed to catch any strands of fiber or dust that could be on the disc before it is extracted. The disc itself is surrounded by the "spine", a plastic ring (actually square on the outside edge) with a thick, straight rim-like edge, which extends outside of and latches into the caddy, serving as a cover. When the disc is inserted into the player, both the disc and the spine are extracted from the caddy and contained inside the player.

[edit] Advantages of CEDs

CED players, from an early point in their life, appealed to a lower-class market than VHS, Betamax, and Laserdisc; although the video quality was sub-par compared to other formats, and the players frequently skipped and exhibited other problems, CED players became very popular among middle- and lower-class families, especially after RCA dramatically slashed the prices of unsold CED players.^[15]

Like VCRs, CED videodisc players had features like rapid forward/reverse and visual search forward/reverse. They also had a pause feature which blanked the screen as CED could not perform freeze frame. Since they were a disc-based system, they did not require rewinding. Early discs were generally monaural but later discs included stereo sound. Other discs could be switched between two separate mono audio tracks, providing features such as bilingual audio capability.

Each side of a CED disc could be split into up to 63 "chapters", or bands. Two late RCA players (the SJT400 and SKT400) could access these bands in any given order. Novelty discs and CED-based games were produced whereby accessing the chapters in a specified order would string together a different story each time. However, only a few were produced before the halt of CED player manufacturing.^[18]

[edit] Disadvantages of CEDs

In comparison to VCR and laserdisc technology, CEDs suffered from the fact that they were a phonograph-like contact media. RCA estimated the number of times a CED could be played back, under ideal conditions, was 500,^[19]. By comparison, a clean, laser rot-free laserdisc could be played unlimited times. A VHS tape could be played a "reasonable"^{[citation needed]} amount of times in 20-25 years. Being that the system used a stylus to read the discs, it was necessary to regularly change the stylus in the player to avoid damage to the videodiscs.

Worn and damaged discs also caused problems for consumers. When a disc began to wear, video and audio quality would severely decline, and the disc would begin to skip more.^[19] Several discs suffered from a condition called "video virus", where a CED would skip a great deal due to dust particles stuck in the grooves of the disc. However, playing the disc several times would generally solve this problem.^[20]

Unlike VHS, CEDs required a disc flip at some point during the course of the film, due to the fact that only sixty minutes of video could be stored per side. If a feature ran over two hours, it was necessary to insert another disc. This problem was not unique to CEDs, as Laserdiscs presented the same difficulty

[edit] Available CED Material

[edit] Hardware

CED players were manufactured by four companies - RCA, Hitachi, Sanyo, and Toshiba, but seven other companies marketed players manufactured by these companies.^[21][22]

[edit] Software

Upon release, 50 titles were available for the CED; along with RCA, CBS Video Enterprises (later CBS/FOX Video) produced the first 50 titles^[14]. Eventually, Disney, Paramount Pictures, MCA, MGM, Vestron Video, and other labels began to produce CED discs under their own home video labels, and did so until the end of disc manufacturing in 1986.

[edit] Milestones

• The first movie distributed in letterbox widescreen format, Amarcord, was released on CED in 1984.
• The first movie title on the format was "Race For Your Life, Charlie Brown", released in March 1981.

[edit] See also

• Videodisc
• Laserdisc

[edit] Resources

• Cowie, Jefferson R. Capital Moves: RCA's Seventy-Year Quest for Cheap Labor. Ithaca, N.Y.: Cornell University Press, 1999. ISBN 0-8014-3525-0.
• Daynes, Rob and Beverly Butler. The VideoDisc Book: A Guide and Directory. New York: John Wiley and Sons, 1984. ISBN 0-471-80342-1.
• DeBloois, Michael L., ed. VideoDisc/Microcomputer Courseware Design. Englewood Cliffs, N.J.: Educational Technology Publications, 1982. ISBN 0-87778-183-4.
• Floyd, Steve, and Beth Floyd, eds. The Handbook of Interactive Video. White Plains, NY: Knowledge Industry Publications. 1982. ISBN 0-86729-019-6.
• Graham, Margaret B.W. RCA and the VideoDisc: The Business of Research. (Also as: The Business of Research: RCA and the VideoDisc.) Cambridge: Cambridge University Press, 1986. ISBN 0-521-32282-0, ISBN 0-521-36821-9.
• Haynes, George R. Opening Minds: The Evolution of Videodiscs & Interactive Learning. Dubuque, Iowa: Kendall/Hunt Publishing Co., 1989. ISBN 0-8403-5191-7.
• Howe, Tom. CED Magic: The RCA VideoDisc Collector's Guide. Portland, OR: CED Magic, 1999. ISBN 0-9670013-0-7. (CD-ROM)
• Isailovi´c, Jordan. VideoDisc and Optical Memory Systems. Englewood Cliffs, N.J.: Prentice-Hall, 1985. ISBN 0-13-942053-3.
• Lardner, James. Fast Forward: Hollywood, the Japanese, and the VCR Wars. (Also as: Fast Forward: Hollywood, the Japanese, and the Onslaught of the VCR.) New York: W. W. Norton & Co Inc., 1987. ISBN 0-393-02389-3.
• Lenk, John D. Complete Guide to Laser/VideoDisc Player Troubleshooting and Repair. Englewood Cliffs, N.J.: Prentice-Hall, 1985. ISBN 0-13-160813-4.
• Schneider, Edward W., and Junius L. Brennion. The Instructional Media Library: VideoDiscs, (Volume 16). Englewood Cliffs, NJ: Educational Technology Publications. ISBN 0-87778-176-1. 1981.
• Sigel, Efrem, Mark Schubin and Paul F. Merrill. Video Discs: The Technology, the Applications and the Future. White Plains, N.Y. : Knowledge Industry Publications, 1980. ISBN 0-914236-56-3. ISBN 0-442-27784-9.
• Sobel, Robert. RCA. New York: Stein and Day/Publishers, 1986. ISBN 0-8128-3084-9.
• Sonnenfeldt, Richard. Mehr als ein Leben (More than One Life). ?, 2003. ISBN 3-502-18680-4. (In German.)

• Journals:
  • The Videodisc Monitor
  • Videodisc News
  • Videodisc/Optical Disk Magazine
  • Video Computing

[edit] References

[edit] External links

• The 'Total Rewind' VCR museum, covering CED and other vintage formats
• RCA VideoDisc Web Site - CED Magic
• The LaserDisc Database - LD/CED/VHD discs, profiling and marketplace

v • d • e  Industrial & home video media
Magnetic tape	VERA (1952) - 2 inch Quadruplex videotape (1956) - 1 inch type A videotape (1965) - 1/4 inch Akai (1967) - U-matic (1969) - Cartrivision (1972) - Video Cassette Recording (aka VCR) (1972) - V-Cord (1974) - VX (aka "The Great Time Machine") (1974) - Betamax (1975) - 1 inch type B videotape (1976) - 1 inch type C videotape (1976) - VHS (1976) - VK (1977) - SVR (1979) - Video 2000 (1980) - CVC (1980) - VHS-C (1982) - M (1982) - Betacam (1982) - Video8 (1985) - MII (1986) - D1 (1986) - S-VHS (1987) - D2 (1988) - Hi8 (1989) - D3 (1991) - D5 (1994) - Digital-S (D9) (199?) - S-VHS-C (1987) - W-VHS (1992) - DV (1995) - Betacam HDCAM (1997) - D-VHS (1998) - Digital8 (1999) - HDV (2003)
Optical discs	LaserDisc (1978) - Laserfilm (1984) - CD Video - VCD (1993) - DVD-Video (1996) - MiniDVD - CVD (1998) - SVCD (1998) - FMD (2000) - EVD (2003) - FVD (2005) - UMD (2005) - VMD (2006) - HD DVD (2006) - Blu-ray Disc (BD) (2006) - DMD (2006?) - AVCHD (2006) - Tapestry Media (2007) - Total Hi Def (2007) - HVD (TBA) - PH-DVD (TBA) - SVOD (TBA) - Protein-coated disc (TBA) - Two-Photon 3-D (TBA)
Grooved Videodiscs	Baird Television Record aka Phonovision (1927) - TeD (1974) - Capacitance Electronic Disc aka CED (1981) - VHD (1983)