Archived — Notice SMBR-005-97

Government Notices
Department of Industry

Radiocommunication Act

Notice No. SMBR-005-97 – Use of Lines 10 to 12 of the Vertical Blanking Interval of NTSC/M System Television Signals

The Department announces amendments to Broadcast Transmission Standard No. 3 (BTS-3), Issue 2 to allow television broadcasting undertakings to transmit ancillary data on lines 10 to 12 of the Vertical Blanking Interval (VBI) of the NTSC/M television signal without requiring amendment of the broadcasting certificate. However, ancillary data services that are neither broadcasting nor program-related may require a specific radio authorisation. The Department is currently reviewing the matter to determine what authorisation requirements should apply for the provision of these services.

For ancillary data services that are deemed to be broadcasting or program-related, potential users are reminded of the policy of the Canadian Radio-Television and Telecommunications Commission (CRTC) regarding these services (Public Notice 1989-23).

The operational conditions for the use of VBI lines 10 to 12 are similar to those for other ancillary data transmissions, i.e. such use will not compromise the integrity of the television picture nor cause harmful interference to other television channels.


The insertion of data on VBI lines 10 to 12 affected certain older receivers and susceptible cable decoders which have been gradually phased out. The Department, as well as the industry, believe that it is no longer necessary to continue with the present practice of requiring experimental authorization for the use of these lines.

Copies of BTS-3, Issue 2 are available electronically on the Internet at the following WWW address: Spectrum Management and Telecommunications

Dated at Ottawa this 20th day of November 1997.

R.W. McCaughern

A/Director General
Spectrum Engineering Branch

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