Foreword
Committees responsible
Specification
1. Scope
2. Abbreviations and definitions
3. TTA categories
4. General
5. Line interface
6. Signalling
7. Outgoing calls
8. BSP signals during message transmission
9. Automatic repeat attempts
10. Incoming call
11. Call clearing
12. Intermediate telex terminal apparatus (I-TTA)
13. Marking
14. Instructions for use
Appendices
A. Information to be provided by the supplier for
test purposes
B. General conditions for test
C. Standard test procedures
D. General tests
E. Modem tests
Tables
1. Requirements and features specific to TO-TTA,
RO-TTA, RT-TTA and FE-TTA
2. Message storage and security features specific
to RT-TTA and RO-TTA
3. Power and voltage levels
4. Telegraph characters
5. Tolerances
6. Exchange simulator transmission
7. Exchange simulator transmission
Figures
1. Power and voltage limit curves
2. Measurement of longitudinal output
3. Exchange simulator transmission: PTS discrimination
and commencement of selection
4. Exchange simulator transmission: call collision
and response to WRV signal
5. Exchange simulator transmission: commencement of
SPC selection
6. Measurement of transmit distortion
7. Deviation of d.c. wetting current
8. SCVF I-TTA automatic changeover
9. Test circuit for measuring transmit frequency and
output signal power
10. Measurement of receiver margin
11. Measurement of received signal level
12. Receive signal level attenuation
13. Measurement of return loss and transverse power
level limits
14. Measurement of longitudinal conversion loss
15. Transverse conversion loss
16. Measurement of DC resistance