March 2000 © TOSHIBA TEC
9-17
DP120F/DP125F Dialing and Communication Procedure
b-2)
Probing/Ranging (Phase 2)
Line characteristics are measured, then the parameter setting for modulation such
as the modulating speed, is made.
•
Transmitter
•
Receiver
Signal name
INFO sequence
Tone B
Tone B
Line probing signal
L1
Line probing signal
L2
Abbreviation
INFO0c
B
B
L1
L2
Meaning
It indicates modem capability such
as modulating speed and frequency
transmission capability (two fre-
quency bands - high and low - used
for measuring the line characteris-
tics), and requests for adjusting.
Synchronization between modems
by 1200-Hz tone
Tone for analyzing the line charac-
teristics by probing
Remark
Transmission rate: 600 bps
B is a signal that shifts phase
B 180°.
Probing is to measure the line
characteristics.
Tone between 150 Hz and
3750 Hz in units of 150 Hz
Signal name
INFO sequence
Tone A
Tone A
INFO sequence
Abbreviation
INFO0a
A
A
INFO0h
Meaning
It indicates the modem capability
such as the modulating speed and
frequency transmission capability.
Synchronization between modems
by 2400-Hz tone
Based on the analysis of the line
probing signal sent from the trans-
mitter, it indicates the pre-empha-
sis filter and modulating speed to
be used for the data transmission.
Remark
Transmission rate: 600 bps
A is a signal that shifts phase
A 180°.
Transmission rate: 600 bps
Summary of Contents for DP120F
Page 1: ...PLAINPAPERFACSIMILE File No 31200001 R0112216901 TTEC ...
Page 401: ...DP120F DP125F Circuit Description 7 92 March 2000 TOSHIBA TEC 07 05 00 Fig 7 5 1 ...
Page 656: ...DP120F DP125F Troubleshooting 11 44 March 2000 TOSHIBA TEC ...
Page 700: ...DP120F DP125F Appendix 12 2 March 2000 TOSHIBA TEC 1 2 Error Count List ...
Page 701: ...March 2000 TOSHIBA TEC 12 3 DP120F DP125F Appendix 1 3 Function List for Maintenance ...
Page 702: ...DP120F DP125F Appendix 12 4 March 2000 TOSHIBA TEC 1 4 Drum Unit ...
Page 703: ...March 2000 TOSHIBA TEC 12 5 DP120F DP125F Appendix 1 5 Memory Dump List ...
Page 706: ...SHUWA SHIBA PARK BLDG A 2 4 1 SHIBA KOEN MINATO KU TOKYO 105 8524 JAPAN ...