Methods of measurement on teletext receivers and decoders

Abstract

The object of this standard is to standardise the conditions and methods of measurement to be used for the study of receivers and decoders for teletext broadcasting. Limiting values of the various quantities are specified but may need modification with increasing experience gained from equipment operating in the field. The standard constitutes a catalogue of selected measurements for assessing the essential properties of equipment of a given type. It is not limiting; if necessary additional measurements may be carried out. The recommended methods apply to a complete receivers or to decoding equipment. They also apply to that subunit of a complete receiver or decoder concerned with the acquisition and decoding of the data signal ignoring interface and power supply circuits. It should be realised that the measurements proposed and the limiting values quoted are subject to modification as mehods are refined and with the development of decoding techniques.