BS 6789-2:1984
Withdrawn
A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.
Hardcopy , PDF
02-08-2013
English
30-03-1984
Foreword
Committees responsible
Specification
Section one. General
1. Scope
2. Abbreviations, definitions and notation
3. General requirements and test conditions
4. Information to be provided by the supplier
5. Electrical network connection methods
Section two. Electrical characteristics of apparatus
6. Apparatus on-line (non-signalling state)
7. Speech transmission process
Appendices
A. General conditions of test
B. Methods of test
Tables
1. Coordinates of voltage limit curves for d.c.
characteristics
2. Limits of sending sensitivity for line lengths up
to and including 3 km
3. Limits of sending sensitivity for line lengths in
the range over 3 km to 7.5 km
4. Limits of noise levels for noise criterion curve
NC 15
5. Data required to calculate Z
6. Psophometric weighting characteristics
Figures
1. D.C. characteristics: upper limit for type B
apparatus
2. Measurement of free field sound pressure used in
the determination of sending sensitivity
3. Physical test arrangement for determining the
sending characteristic
4. Limits of sending sensitivity for line lengths up
to and including 3 km
5. Limits of sending sensitivity for line lengths in
the range over 3 km to 7.5 km
6. Physical test arrangement for determining the
receiving characteristics
7. Noise criterion curve NC 15
8. Dimensions of test table
9. Position of LST
10. The local telephone system
11. D.C. excited test circuit
12. Axes used in the determination of free field
conditions for 1 m radius sphere
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