Ericsson ZAT 19.2 Operation Manual page 294

15.3 Bandwidth
The modem uses the bandwidth of the telephone network according
to sections 15.3.1 (ITU-T V.21) and 15.3.2 (ITU-T V.22)
ITU-T V.21
The bandwidth of the telephone network
A- channel B- channel
6 980 | 1180 - i660" 1850 3500Hz
Frequency shift keying (FSK) around the frequencies 1080 HZ and 1750 Hz
ITU-T V.22
The bandwidth of the telephone network
A-channel B-channel
1800 2400 3500
guard Hz
guard
Phase shift keying (PSK) with 4 possible phase shifts in both channel
The originating modem normally sends in the lower channel (A
channel), whereas the answering modem sends in the upper
channel (B channel). However, it is possible to transmit in the
opposite channel if desirable.
1 5-6 LZTR104006 R1.00
Zatt14.4/14.4-7 and 19.2/19.2-7