Pioneer
PR-7820/Model 3 (1979/1980)
PR-7820 |
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
arcade video games. Those with a talent for digging could also find them in
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.
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