CXR Larus 80-100-400
Issue 1, July 2006
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5.1322
T1 Transmit Framer
The T1 transmit framer is clocked by the signal selected by the clock select
switch. The signal is frame synchronized with the buffered signal from the
external synchronization bus. It inserts either SF or ESF framing according
to the setting of S1 and produces dual rail output pulses that the output
drivers convert to bipolar framed all ones.
5.1323
Controls and Indicators
The following controls and indicators appear on the front panel of the card:
a. The red FAIL LED lights if the on-card fuse blows.
b. The green CLOCK A/B LED lights when the corresponding clock, either
A or B, is selected.
c. The yellow INPUT A/B LED lights when the corresponding input, either A
or B, is selected.
d. The yellow OVERRIDE LED lights when automatic selection has been
overridden by manual remote selection.
e. The red OUTPUT LOSS LED lights when a loss of one or more outputs
occurs. If both A and B clocks and both input references fail, leaving no
valid signal for the output cards to select, the OUTPUT LOSS LEDs on
all output cards are illuminated and all outputs are suppressed.
f. The front panel MON jack allows for monitoring one of the output signals
with a standard monitoring test set. The Model 54571 has ten outputs
with independent drivers.
5.1324 One-wire
Interface
The one-wire interface allows communication of data between the T1 output
card and the 54550 Information Management Card.
5.1325 Power
An on-card power converter provides the necessary circuit voltages from the
diode-combined A and B -48 volt battery supplies. The on-card fuse, if it
blows, lights the red FAIL LED and provides battery to the Fuse Alarm bus
connecting to pin 10 on the backplane terminal strip TB1.
Note: twenty outputs now
