Electromagnetic compatibility in active telephone sets

Dramatic growth has taken place in modern telecommunication equipment. AM and FM radio transmitter power is very high and it affects telephone set performance. In the worst case subscribers sited near transmission towers cannot hear the other talking party nor even dial the desired number. Usually they have to switch their sets to pulse dial mode in order to communicate. Three Mercosur Institutions (CITEI, IIE and ANTEL) have joint efforts to solve the problems existing in the PTT's outside plant (OSP). The results define measurement techniques and threshold values needed to achieve an adequate electromagnetic compatibility in active telephone sets and also determine a technical procedure for proper OSP construction. This paper describes the measurement techniques, test procedures and limits values used in the Mercosur region.