9
Reverse Path Set-up:
3.
The LBON4000 comes factory set with 2db pads in Position AK1 and AK2. Do Not change value.
Refer to Figure 9.
4.
Return Path attenuators ATT1 and ATT2 are adjusted to match as close as possible the RF return
input levels between Ports 1&2 and Ports 3&4, based on system knowledge of the incoming Return
RF levels from each of the 4 ports.
5.
Adjust ATT5 pad value to insure total return level to the laser is 34
– 50dBmv. Measure the RF levels
at the node input using the Rev T.P. and remember that it is 20dB below the actual signal level.
Please note that the test point is located after the reverse pad, so any adjustments made using the
pad can be read directly from the T.P. port.
Return RF -20db TP
before laser
Return laser
transmitter
ATT5; Return RF
attenuator
ATT1; Return RF
attenuator for
Port 1&2
ATT1; Return RF
attenuator for
Port 3&4
Upstream/Return
Fiber
Figure 9
User Manual
LBON4000
LBON4000 April 2013
