Nortel Networks 553-3001-211 manual Switch SW1 Dchi Configuration

Page 738 of 894 NTAK79 2.0 Mb PRI card

Switch SW1 – DCHI Configuration

This switch enables/disables the on-board DCHI and sets the operating mode of the DCHI. DPNSS1 mode is not supported at this time. For all other countries that do not use DPNSS, use Q.931 mode.

Table 235

Switch SW1

Switch	Down (On)	Up (Off)
SW 1-1	enable DCHI	disable DCHI
SW 1-2	DPNSS1/DASS2	Q.931

Switch SW2 – Carrier Impedance Configuration

This switch sets the carrier impedance to either 120 ohms or 75 ohms. Twisted pair cable is usually associated with 120 ohms. Coaxial cable is usually associated with the 75 ohms setting.

Table 236

Switch SW2

Cable Type	SW 2-1	SW 2-2
75 ohms	Up (Off)	Down (On)
120 ohms	Down (On)	Up (Off)

Switch SW3 – Clock Controller Configuration

This switch enables/disables (H/W) the on-board Clock Controller. Disable the SW 3-2 if the on-board clock controller is not in use.

Table 237

Switch SW3

Switch	Down (On)	Up (Off)	Note
SW 3-1	—	—	Spare
SW 3-2	Disabled	Enabled

553-3001-211 Standard 2.00 September 2004