Carrier Access Access Bank II SNMP - Manual (Page 125)

12-4 9/24/01
12.4.3 Remote Mode: Ringback Tone or 1 Digital Milliwatt
When the Access Bank II - SNMP is powered up in Remote mode, the tone sent during the Self Test
can consist either of the same Ringback dual tone (440 Hz +480 Hz) sent in the Local Mode or a stan-
dard 1 kHz digital milliwatt test signal. In Remote mode, Ringback tone is the default setting.
12.5 1 kHz Digital Milliwatt Test Signal
The 1 kHz digital milliwatt signal test is used to check proper DS0 channel alignment and for isolat-
ing transmission failure problems between the Access Bank II - SNMP and connected switching
equipment.
As specified in AT&T PUB 43801, the transmission of the following repetitive eight byte pattern (1E/
0B/0B/1E/9E/8B/8B/9E) in a given channel should be decoded in a properly aligned receiving termi-
nal as a 0dBm0, 1 kHz sine wave signal:
Table 12-2: Standard Digital Milliwatt Signal
12.6 Network Loopback 1 and 2
12.6.1 Local Mode: No Network Loopback or Network Loopback
Enabled
In the Local mode, setting Network Loopback 1 or 2 switch to ON causes the T1 signal received from
T1 network interface 1 or 2 to be looped back toward T1 line 1 or 2 by connecting the T1 receiver to
the T1 transmitter before the framer chip. See Figure 9-2. T1 signals are sent back to the network
exactly as they were received. No pulse stuffing, BPV correction, or framing is performed that would
corrupt T1 test patterns (such as a QRSS) received from the far end. Channel interfaces are held in the
Trunk Processing state when the Network Loopback switch is activated. The T1 Test 1 or T1 Test 2
LED on the Control Panel shows continuous yellow. All voice channel operations are suspended and
the channel status LED indicators on the back plate show continuous yellow.
Digit No. 1 2 3 4 5 6 7 8
0 0 0 1 1 1 1 0
0 0 0 0 1 0 1 1
0 0 0 0 1 0 1 1
0 0 0 1 1 1 1 0
1 0 0 1 1 1 1 0
1 0 0 0 1 0 1 1
1 0 0 0 1 0 1 1
1 0 0 1 1 1 1 0