Kuhnt AS55 Series, Service Manual

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SERVICE MANUAL AS55X
55Xseries_manual_V3.22 (18-08-15) www.kuhnt.com 53

Tone generation during call-termination
During the call-termination phase the AS55X normally generates a busy tone to the
ISDN interface. If the PBX is wanted to generate this tone, it can be set here.
This function is controlled by the progress indicator “in-band information available”,
but not all PBXs do interpret this indicator correctly.
Default value: ... by AS55X

CRC 4
The PRI interface normally uses CRC 4 for synchronisation and error detection. If it
does not use CRC 4 you have to switch off this option.
Default value: On
5.3.3 Synchronisation interface (ISDN AUX)

Synchronisation mode
This option is greyed-out if the AS55X is working in PassThrough or slave mode.
Otherwise you can choose the operation mode of the synchronisation interface. This
is necessary if the PBX needs synchronised clocks at different primary rate interfaces.
o
Off (default value)
The AS55X generates its own clock.
o
Additional terminal
To synchronize the AS55X main interfaces clock to an existing PRI clock, connect the
ISDN AUX interface parallel to your PBX (as an additional terminal) to the wired
network (e.g. with an Y-adaptor). In this case the receive path of the connection are
in high-impedance-state. The AS55X gets its clock rate from the wired network
Notice: If the ISDN AUX interface is not connected or the received clock rate
is incorrect, the AS55X generates its own clock.
o
Single terminal
To synchronize the AS55X main interfaces clock to an existing PRI clock, connect the
ISDN AUX interface to a free PRI interface of your PBX. The AS55X has to be exclusive
participant (a single terminal) on this ISDN Bus. The AS55X gets its clock rate from the
PBX.
Notice: If the ISDN AUX interface is not connected or the received clock rate
is incorrect, the AS55X generates its own clock.