Link Electronics Modem OP/1 Optional Internal Telephone Modem for PDR-885
The PDR-885 is a Closed Caption Encoder with anintegral Decoder for inserting caption and text dataon Line 21 of the NTSC signal. However, thisimportant function is only the beginning of thePDR-885 capabilities.
Caption and Text data may be inserted in eitherfield of the Vertical Blanking Interval. In addition,data on the incoming video signal may berecovered from either field of the VBI. Thisincoming data may be displayed as OpenCaptions, using the built-in Closed CaptionDecoder, and captured by a computer utilizing thePDR-885's serial data port. Each of theseimportant functions, Encoding, Decoding, and DataRecovery may be done simultaneously.
The Closed Caption Decoder's functions may becontrolled from the front panel while the Encoderand Data Recovery functions are controlled via theserial data port. The video data path approachesperfection, with differential phase and gain errorsless than 0.1? 0.1% respectively. Videobandwidth is >26MHz while Signal to Noiseexceeds 60dB. Inputs and outputs are provided forcomposite NTSC video as well as Component (RY/B-Y/Y) and S-Video.
If composite video is used, a high performancerelay provides power-off by-pass of the programvideo. For remote captioning applications, asecond serial port is available as a modem input.Both serial ports may be configured for RS-232 orRS-422 I/O, with optional plug-in PCB. An internaljumper allows baud rate selections of 1200 to 9600bps. A modem and computer may be connectedsimultaneously to process local and remotecaption data, only one active at a time.
Front panel LED's show the unit status and thepresence of data on the incoming video. A pair offront panel push-buttons allow the user to run anencoded test message or to place the unit in bypass mode.
The PDR-885 is ready for V-Chip technology. Thistechnology will allow parents to block violent orotherwise offensive television programming fromtheir TV sets. LINK Electronics is incorporating thistechnology in the firmware of the PDR-885. ThePDR-885 handles the automatic repetition of the"V-Chip" data and can interleave it with existingLine 21 Closed Caption data. An optional plug-inmodem is available that operates at 1200 or 2400baud.