BusinessPhone Communication Platform 4.0
Installation Instruction ASB 150 02 > Boards For ASB 150 02

## BTU-D (ROF 157 5112/1) and REG (ROF 157 5112/2)

#### DIP-switches in position 197 and 200

Depending on the firmware used, this board enables either ISDN or CAS function. The PROM set is available for CAS (LZY203 2212/1) or ISDN PRA (LZY203 2213/1). DIP-switch pos. 197 on BTU-D selects the register function of the board. The switch 200 is reserved for future use.

197/1 | 197/2 | Function
OFF | OFF | digital trunk MFC | only BTU-D
ON | digital trunk MFE
ON | OFF | Register MFC | BTU-D or REG.
ON | Register MFE

#### DIP-switches in positions 198 and 199

Selection of ground strapping for the coax 75 W or selection of the 120 W twisted pair interface.

198/1 199/1 | 198/2 199/2 | Function
OFF | OFF | 120 W connection (Factory setting)
OFF | ON | screen connected to ground
ON | OFF | screen connected to ground via 1nF capacitor

On factory delivery the switches are set to OFF-position = no ground thus enabling 120 W interface with a twisted pair cable. These DIP-switches connect the 75 W interface coax screen to ground, either directly to 0V or via a 1 nF capacitor. DIP-switch 198 switches the receiver and 199 the transmitter side. The screen shall normally be grounded on the transmitter side. Normally, the screen on the reception side is not connected to ground. Refer to local market requirements.

#### Ranges on the interface of the BTU-D

This interface covers the short distance to the next NT or Line Terminating Unit as the end point of a public or private network. The range is only defined in terms of the covered attenuation by the interface that is 6 dB. If required choose cables with low attenuation to achieve a maximum distance.

For ranges exceeding 6 dB attenuation additional digital data transmission equipment is required. Line Terminating Unit (LTU) ASB 501 04 is available for such purposes.

Some markets (e.g. Austrian PTT) require the use of a double-shielded interface cable. The outer shield should be connected to frame earth and the inner shield should be connected to 0V on the board. A 20 m long standard cable is available with the ERICSSON ordering number TSR 901 0481/20000.

Revision: A © Ericsson Enterprise 2003