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Pioneer PR-7820/Model 3 (1979/1980)

DiscoVision
PR-7820
Pioneer
Model 1, 2 & 3

Thanks to Reinhold for the above pictures.

The first and only player to conform to the MCA DiscoVision specifications is also arguably one of the best players to view DiscoVision discs on. The player is an industrial player, put to use in nearly every General Motors dealership in 1979-80 to show off the 1980 line of autos as well as a source of training films on everything from carburetor repair to customer service. This model (under the nameplate Pioneer Model 3) was tucked neatly underneath thousands of Dragon's Lair arcade video games. Those with a talent for digging could also find them in Space Ace arcade conversions. Just goes to show you the player can really take the punishment of constant use.

Pressing Play spins the disc in the opposite direction from conventional LaserDisc players as the pickup is mounted above the disc. The disc then slides underneath the pickup and begins playback. Genuinely suited to play the General Motors discs, the player gets programmed by a data signal, encoded on Analog right during in the first 100 frames. The onboard memory is loaded and the program executed for what ever the disc program contains. The feature can be disabled by shutting off Audio Right/2 before disc sync is attained. A programming example was the Buick's 1980 line of cars which was presented as a short little program, which then returned to the beginning of the disc and and presented a menu of choices like standard features and all available options. It really was very ingenious. Today, a very similar functionality is found with CD-Rom discs loaded into Windows95 workstations with Auto Insert Notification which starts the program contained on the ROM automatically. An amazing accomplishment for MCA considering it was all conceived and executed in 1978, a full 2 years before the IBM PC was even introduced.

The player incorporates a fully solid-state tangential system to compensate for time based correction errors, rather than utilizing a moving mirror. This practice was dropped from all LaserDisc players after the PR-7820 was discontinued until being reintroduced 6 years later with the Pioneer LD-909 player. The system yields an excellent picture, but because of the newness of the CLV Extended play format at the time of its introduction, suffers from crosstalk problems on CLV discs. Regardless, when properly adjusted, the PR-7820 will play nearly any disc it is offered.

On startup, the player will search to Frame 1. Since nearly all DiscoVision Side 1's begin with Frame 0 buried within the opening bumper and hold on 0 until the film actually starts, standard playback will avoid the bumpers. The exception is CLV discs, which, like the LD-660, simply begins playback at the inside limit. Again, this can vary from player to player.

The player also ignores all normal Philips code based information, including chapter number, end of side and AutoStop codes. This allows the disc to scan beyond the coded end of side and for the proper playback of Frenzy Side 5. Since CLV was viewed as a Playback only format, the player does not include Pause or Searching functions on these discs. However, the scan function is so quick, you can scan from beginning to end of a CLV disc in just a few seconds.

Advantages Disadvantages
Gas Tube Laser for superior tracking
Ignores disc based codes for Auto Picture stop, End of side, beginning of side, etc.
Designed for GM discs
Plays nearly every disc
No CLV Pause or Search support

Copyright 1998 Blam Entertainment Group
Thanks to Blain Young for use of the material.

The archive site has a copy of the Operation Manual for the PR7820. If you would like a copy please send an email requesting the manual for this player.