Carrier Grounding - Meridian Nortel 1 Option 11C Technical Reference Manual

Carrier grounding

Table 151
Carrier shield grounding switch settings
Switch
S4-1
S4-2
NTAK79 provides for the capability of selectively grounding the shield of the
Tx and/or Rx pairs of the carrier. Closing (down) the on-board switch will
apply FGND to the appropriate carrier cable shield. The switch settings are
shown below.
Carrier Pair
Rx shield
Tx shield
Receiver functions
The receiver extracts data and clock from an AMI (Alternate Mark Inversion)
coded signal and outputs clock and synchronized data. The receiver is
sensitive to signals over the entire range of cable lengths and requires no
equalization. The clock and data recovery meets or exceeds the jitter
specifications of the CCITT recommendation G.823 and the jitter attenuation
requirements of CCITT recommendation G.742. This provides jitter
attenuation increasing from 0 dB to 60 dB over the frequency range from
about 6 Hz to 6 KHz.
Transmitter functions
The transmitter takes the binary (dual unipolar) data from the PCM
transceiver and produces bipolar pulses which conform to CCITT
recommendation G.703 pulse shape.
Loopbacks
The remote loopback function causes the device to transmit the same data that
it receives using the jitter attenuated receive clock. The data is additionally
available at the receive data outputs. Local loopback causes the transmit data
and clock to appear at the receive clock and data outputs. This data is also
transmitted on the line unless transmit AIS is selected.
NTAK79 2.0 Mb PRI card
On
Open
Open
Option 11C and 11C Mini
Page 485 of 544
Off
GND
GND
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