User's Guide Part 2

Configuring the PTP 600 Chapter 6 Operation
phn-0896_009v003
6-50
UNDER DEVELOPMENT
Feb 2010
Cable Length
The Cable Length setting is applicable in T1 mode only and shows the cable length
specified in the installation wizard.
Loopback
Allows the T1 or E1 data stream to be looped back at the copper or wireless interface.
During normal operation the loopback must be set to "None". It may be helpful during
installation to test the telecoms links by performing loopback connections.
A "Copper" loopback connects the received data on a given telecoms interface to the
transmit interface. A "Copper" loopback may be used, in conjunction with a Bit Error
Rate Tester, to confirm that the correct connections have been made to the ODU. This
mode cannot be used for resistance tests as it is only capable of looping back valid
telecoms signals.
A "Wireless" loopback sends the telecoms data received across the wireless link back
across the link on the same Telecom channel. The link may be checked using, for
example, a Bit Error Rate Tester to ensure that no errors are detected.
A typical T1 or E1 installation might include a "Copper" loopback on the local unit
followed by a "Wireless" loopback on the remote unit.
It is important to remove all loopbacks on channels for normal operation. Alarms on
the Home Page indicate the presence of loopbacks on either channel.
Lowest Telecoms Modulation Mode
The user defined lowest modulation mode at which telecoms data can be sent. If the
link cannot sustain telecoms data in this mode then the effective lowest modulation
mode may differ
Lowest Dual Payload Modulation Mode; Lowest Single Payload Modulation
Mode
Indicate the effective lowest modulation mode at which telecoms data can be sent,
subject to wireless capacity and latency limitations. Under some circumstances, these
settings may differ from the user defined Lowest Telecoms Modulation Mode
described above.