The SUBUK (SUBscriber Line ANalog) cards are telephone interface units. 12 two wire subscriber connections are available on each unit.
The unit simulates the functions of the exchange, detects the corresponding telephone signals and transmits these to the EXLAN card on the exchange side.
Each of the 12 channels on the SUBUK can be individually configured for phone to phone mode of operation to allow a hot line connection to be implemented.
When one or more SUBUK units are installed in an SDM chassis, then one ringing generator unit RIGEN/MIRIG must be installed to provide ringing to the telephones.
The SUBUK provides access for the following different line types:-
Phone to Phone
- Ground key ringing
- Automatic 4s ringing on lifting of the handset
Phone to Exchange
- Direct exchange line (Standard POTS)
- Loop calling PBX lines
- Earth calling PBX lines
- PBX extensions
The following conditions are detected:-
On/Off hook
Ground key
Pulse dialing
Earth start (Earth calling)
The following conditions may be applied to the line:-
Normal constant current feed
Parked current feed
Polarity reversal
Ringing
Metering pulses
Tip open (Earth calling idle)
Line disconnected
