Meridian Nortel 1 Option 11C Technical Reference Manual page 401

Table 123
MFC Frequency values (Part 1 of 2)
Digit
1
2
3
4
5
6
7
8
9
10
11
12
MFC signaling involves two or more levels of forward signals and two or
more levels of backward signals. Separate sets of frequencies are used for
forward and backward signals:
• Forward signals. Level I forward signals are dialed address digits that
identify the called party. Subsequent levels of forward signals describe
the category (Class of Service) of the calling party, and may include the
calling party status and identity.
• Backward signals. Level I backward signals (designated "A") respond
to Level I forward signals. Subsequent levels of backward signals (B, C,
and so on) describe the status of the called party.
Table 123 on page 401 lists the frequency values used for forward and
backward signals.
Forward direction
DOD-Tx, DID-Rx
1380 Hz + 1500 Hz
1380 Hz + 1620 Hz
1500 Hz + 1620 Hz
1380 Hz + 1740 Hz
1500 Hz + 1740 Hz
1620 Hz + 1740 Hz
1380 Hz + 1860 Hz
1500 Hz + 1860 Hz
1620 Hz + 1860 Hz
1740 Hz + 1860 Hz
1380 Hz + 1980 Hz
1500 Hz + 1980 Hz
NT5K21 XMFC/MFE card
Option 11C and 11C Mini
Page 401 of 544
backward direction
DOD-Rx, DID-Tx
1140 Hz + 1020 Hz
1140 Hz + 900 Hz
1020 Hz + 900 Hz
1140 Hz + 780 Hz
1020 Hz + 780 Hz
900 Hz + 780 Hz
1140 Hz + 660 Hz
1020 Hz + 660 Hz
900 Hz + 660 Hz
780 Hz + 660 Hz
1140 Hz + 540 Hz
1020 Hz + 540 Hz
Technical Reference Guide