1990 - 1993 Four Competing Digital Systems Emerge
1990 – FCC Chairman Sikes statement to the Advisory Committee sets the stage for disruption - none of the twenty-three proposed systems was capable of delivering HDTV in a single 6 MHz broadcast television channel...
1990 - General Instrument announces DigiCipher
1990 – Advanced Television Research Consortium (Sarnoff, Thomson, Philips and NBC) announce Advanced Digital HDTV (AD-HDTV)
1990 – Zenith and AT&T announce Digital Spectrum Compatible HDTV (DSC-HDTV)
1990 – MIT and General Instrument announce ATA-Progressive (later renamed Channel-Compatible DigiCipher)
1991 – Initial concept-level demonstrations of the four digital systems are given at NAB ’91. Skeptics abound and the industry focus remains on analog system proposals, notably ACTV and Narrow-MUSE
1991 – initial descriptions of the four digital systems are submitted to ACATS, for "pre-certification" review and determination whether the system would remain under consideration
Advanced Digital Television (Feb 27, 1991)
Digital Spectrum Compatible HDTV
1991 – full descriptions of the four digital systems are submitted and presented to ACATS for "certification" as being deemed viable and worthy of testing
Digital Spectrum Compatible HDTV (Sept 29, 1993)
Channel-Compatible DigiCipher (May 14, 1992)
1991 – Testing of the proposed systems begins at the ATTC, starting with the two analog systems, ACTV and Narrow-MUSE
Dec 3, 1991 - NY Times article "A Milestone in High-Definition TV"
1992 – After completing its testing, General Instruments demonstrates the world’s first high-power digital TV broadcast with its DigiCipher system.
1992 – the four digital systems are in intense competition at NAB ’92 (see pages on each of the systems)
1992 – After completing its testing, ATRC demonstrates the world’s first simulcast of analog NTSC TV and digital HDT, at NBC's WRC-TV station in Washington, featuring WRC's live news and up- and down-conversion between high definition and standard definition. This was the precedent for the industry's subsequent analog to digital transition.
Fall 1992 - After completing their testing, each of the four candidate digital systems proposes improvements (see pages on each of the systems)
1993 – The ACATS Advisory Committee “Special Panel” convened to review test results and select the winning system. It concludes that the digital systems are superior to analog proposals, but it fails to select a winner among the four competing digital systems