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4 Software Operation | MIX 56 User Manual |
PERFORMING DIAGNOSTICS
Running Loopbacks
! ALERT
ALERT! When a loopback is running, the
The following loopbacks can be set from the Loopbacks screen:
Low Speed “Line”: The signal is sent through the DS1 LIU (Line Inter- face Unit) and looped back before reaching the Encoder/Decoder. The DS1 Received signal is looped back out as the DS1 Transmitted signal.
Low Speed “Local”: The demultiplexed DS1 signal from the M13 MUX is encoded and sent to the DS1 LIU Equalizer, where it is looped back through the DS1 LIU Decoder, and then multiplexed and added to the DS3 stream by the M13 MUX.
High Speed “Line DS3”: The received signal is sent through the DS3 LIU and through the M13 MUX Decoder, where it is looped back through the Encoder and put onto the DS3 stream. The DS3 Received signal is looped back out as the DS3 Transmitted signal.
High Speed “Local DS3”: The signal is sent through the DS1 LIUs, multi- plexed, and looped back before reaching the M13 MUX Encoder.
High Speed “Line, DS1 Ch xx in DS3”: The signal path is the same as the “Line, DS3” loopback, but instead of the entire DS3 signal being looped back, an individual DS1 channel of the Muxed DS3 signal is looped back.
The illustration below shows the path of each loopback.
DS3 LIU |
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| M13 MUX |
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| DS1 LIU |
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Noise |
| Clock & |
| DS3 | DS2 | Tributary | Tributary |
| Jitter | Pulse | Line | |
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| Framer & | Framer & |
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Crosstalk | Equalizer | Data | Decoder | Encoder | ||||||||
M32 | M21 | Mapper | Interface | Attenuator | Shaper | Driver | ||||||
Filter |
| Recovery |
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| Demux | Demux |
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Line | Pulse |
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| M23 Mux | M12 Mux | Tributary | Tributary |
| Clock & | Peak |
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| Encoder | & DS3 | & DS2 | Decoder | Date | Equalizer | ||||||
Driver | Shaper |
| Mapper | Interface | Detector | |||||||
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| Framer | Framer |
| Recovery |
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MIX 56 Loopback Options
Telect, Inc. |