Grass Valley PDR100 - Manual (Page 14)

Chapter 1 Introduction
1-2 PDR100 Installation
Operation Overview
Program video is input to the system in component serial digital, component analog,
or composite analog format, converted to parallel digital format, and routed to the
Disk Recorder circuit board by the on board video router. The parallel digital signal
is compressed (JPEG) and stored on the hard disk.
Upon recovery, the compressed parallel digital component video is decompressed and
routed to the output circuitry where it is converted back to serial digital or analog
format. The composite output undergoes an additional conversion back to either the
NTSC or PAL format. The composite output circuit board supports up to four
composite program outputs and a monitor channel. The monitor channel can have
time code burned in.
Each video channel can be supported by up to four channels of audio. A separate
audio circuit board is required for each four channels of audio input or output. The
audio signal is stored on a hard disk along with the video. For playback, the audio is
recovered from its storage location and output with the same video signal relationship
it had when recorded.
Control of the hard disks is accomplished by the Disk Recorder circuit boards, which
also provide the JPEG compression/decompression. The Master Disk Recorder can
control as few as 4 and as many as 12 hard disks. A Slave Disk Recorder can be added
to control between 4 and 12 additional hard disks. The total number of hard disks that
can be accommodated by a single PDR 100 (with PDX103 Disk Expansion unit) is
24.
The PDX103 is an optional Disk Expansion Unit containing its own power supply
and as many as 16 additional hard disks in a 7-inch (four rack units) high by 25.5-inch
deep, and 19-inch wide unit. The Disk Expansion Unit is delivered with either 8 hard
disks (2 banks of 4 to support 2 Disk Recorder boards in the PDR 100, a single bank
of 8 to support 1 Disk Recorder board), or with 16 hard disks to fully utilize the
capacity of 2 Disk Recorder boards.