FIELD: telecommunications. SUBSTANCE: system provides access to external service through telemetry call from user side output equipment, for example, alarm signal transmitter, information about state of unit of equipment. Operations and functions of user does not affect call. Such user functions as call wait are suppressed during telemetry call and resume their operations when it is terminated. In addition access from user side equipment to external service is provided through telephone line without restriction of user choice of telephone functions and equipment. EFFECT: increased functional capabilities. 29 cl, 3 dwg
