Toshiba CTX28 用户手册
T1
RDTU Installation
8-8
Strata CTX I&M 06/04
RDTU3 Self Test and CSU Test Switch
1. Remove the RJ45 cable to perform the Self Test.
2. Set the SW8 and SW9 switches to On (see
).
3. After self check passes, put the switches back into position for normal operation and insert the
RDTU PCB back into the appropriate slot.
RDTU3 Equalizer Switches
The distance between the Strata CTX, RDTU and CSU or RDTU to other Customer Premise
Equipment (CPE) T1 may vary (0~655 ft.) as shown. (See
Equipment (CPE) T1 may vary (0~655 ft.) as shown. (See
.) The
RDTU interface transmitter must be equalized and its impedance must be matched to the cable
length connecting the RDTU to the CSU or other CPE, T1.
length connecting the RDTU to the CSU or other CPE, T1.
³
Set the appropriate SW1 Equalizer Switch setting and set SW1 to the setting that matches the
RDTU cable length (see
RDTU cable length (see
RDTU3 Loop Back Jumper Plugs
The RDTU PCB provides jumper plugs for loop back testing. Loop back tests are described in
for switch settings for Loop Back tests.
RDTU3 Front Panel Indicators
The RDTU3 PCB provides seven LED indicators to show the status of RDTU: Busy or Idle
condition, Alarm status, and Synchronization status. See
condition, Alarm status, and Synchronization status. See
for the function of each status
shows the LED locations. Busy LED (BSY)—Turns on when one or more RDTU
channels (lines) are in use. Also, when the RDTU does not receive the far end 1.544 mbs carrier
signal, the RDTU will cause the BSY to be on steady.
signal, the RDTU will cause the BSY to be on steady.
Table 8-5
SW8, SW9 RDTU3A Self and CSU Test
Mode
SW8 and SW9
RDTU3A self test and CSU test mode
Both On
All LEDS turn Off
except PSYNCH
or SYNCH
except PSYNCH
or SYNCH
Normal operation (non-loop back)
Both Off
Table 8-6
Equalizer Setting Switch
Mode
Feet from CTX
SW4
SW5
SW6
Short
0 to 133 feet
Off
Off
Off
Semi-short
133 to 266 feet
On
Off
Off
Medium
266 to 399 feet
Off
On
Off
Semi-long
399 to 533 feet
On
On
Off
Long
533 to 655 feet
X
X
On
X = Doesn’t matter.