The Models 9825M and 9825S Modulators and Model 9815 Rear Interface Module (RIM) are Scientific-Atlanta’s latest additions to our well-known product family of Continuum Headend Systems. The Continuum Headend System product family provides users with a vertically oriented, compact, full-featured ensemble of headend functions. Continuum products give today’s video information providers an integrated, high-performance platform for many vital headend applications.

The Models 9825M (mono) and 9825S (stereo) Modulators have been specifically designed to provide support for versatile system architectures where space saving efficiency is of major importance. The Model 9825M Modulator is a full-featured modulator that provides a monaural NTSC television signal on any selected CATV channel between 50-870 MHz. The Model 9825S Modulator has an integrated BTSC stereo encoder that mounts internally, in place of the mono audio board. It is designed for cable television headends that must encode locally originated or satellite-delivered stereo audio programming in BTSC stereo format. An optional SAP (Second AudioProgram) circuit is also available as an integrated feature.

The Models 9825M and 9825S Modulators utilize some of the latest advancements in Scientific-Atlanta technology. Both models provide a new upconverter design that contains a custom ASIC (Application Specific Integrated Circuit). The use of ASIC technology allows the upconverter section of the modulator to consume approximately half the power and is less than half the size of traditional upconverter circuits. The new design maintains excellent RF performance with the added benefit that it can tune from 50-870 MHz in a single device. The Model 9825S Modulator stereo version integrates a true DSP (Digital Signal Processing) BTSC Stereo Encoder and optional SAP module into the modulator. The use of DSP technology for stereo encoding provides unprecedented improvements in stereo separation and distortion that were previously unachievable. Furthermore, by digitally generating the audio subcarrier, no critical calibration of the BTSC signal will ever be required.

The Models 9825M and 9825S Modulators process a baseband video and audio signal to produce a VSB signal at a selected CATV channel frequency. At its inputs, a fully equipped Model 9825S Modulator can accept any NTSC standard video input plus mono, left, right, and SAP baseband audio. Other available inputs include 4.5 MHz audio subcarrier and an external IF port that can accept either digital or composite IF (analog) signals. The Model 9825M Modulator can be used with external stereo encoders or can be upgraded to a Model 9825S Modulator with the installation of a stereo encoder upgrade kit.