Purpose of automatic tests

The purpose of automatic testing is to make it possible to perform rapid tests; circuits found to be "satisfactory" in the course of these will not be subjected to full maintenance tests and the maintenance staff can thus concentrate on making full tests of circuits identified as "doubtful" during the rapid tests.

Automatic tests should be organized in such a way that at least at one end of the group of circuits under test, no staff is required. This end of the circuit will then be said to be "in the passive position", while the end initiating the tests will be said to be "in the active position".

For these tests it is necessary to distinguish between trunks including regenerative equipment and those without. Tests on trunks were no regeneration is involved are dealt with in § 2. Tests on trunks where regeneration is involved are dealt with in § 3.

Note 1 – Unless stated otherwise, the end of the circuit in the active position will be denoted by the letter A and the end of the circuit in the passive position by the letter B throughout this Recommendation.

Note 2 – Where regenerative and non-regenerative sections of the telegraph circuits are connected in tandem (e.g. national extension DT in Figure 3/R.79) the tests to be conducted shall be defined in the framework of bilateral agreements.