3
3.
Before applying power to the amplifier make sure that the forward input level to the amplifier is not too high or damage to
the amplifier might occur. To be on the safe side, you should select the input attenuator to be a max. value (eg: 20 dB)
before powering the LBLE100A.
4.
Plug a 0dB JXP pad into the inter-stage equalizer socket.
5.
Now apply power to the amplifier and measure the amplifier forward output level at the 20 dB output test point. If it is very
low then adjust the value of input attenuator until the desired output level is reached at the highest operating frequency.
Remember that the level measured at the test point is 20 dB lower than the real signal level.
6.
Install the appropriate value JXP pad into the forward input equalizer socket to adjust the output level to be flat across the
full bandwidth. When the output level is flat then the input signal level will be flat too because the inter-stage equalizer is
0dB. Under this condition there will be best CNR across the full bandwidth.
7.
If you plan to use the default setup then install the 9dB JXP pad back into the inter-stage equalizer socket. If your designer
has chosen a different output slope for the amplifier then install the appropriate value. Check that the forward output slope
is 9dB (default) or as set by your system planner.
8.
Repeat the previous steps for each forward output port.
9.
If you are having trouble obtaining the expected output levels then check the input test point to verify that the levels are as
expected at the input of the amplifier. The forward path set up is complete.
10.
For the reverse path, inject into the forward output test point test carriers with the system design input signal level plus 20
dB (because the test point has 20 dB loss) at each end of the upstream band.
11.
Verify that the upstream reference test point (Note: this is commonly called the
“X point” and it is measured at your node, or
optical receiver, or at the 1st downstream amplifier. Consult with your system designer) has the proper upstream output
signal levels. If it does not then select the appropriate JXP pad values and install them in the reverse amplifier output
attenuator and equalizer sockets.
12.
If the levels arriving from each port are not equal then use the reverse input attenuation sockets to balance them.
13.
Record the in/out operating levels and the pad and equalizers used in this station.
Closing the Lid
1.
Before closing the lid, make sure that no foreign matter, dirt, or chips or stands of the grounding mesh wire interfere with the
sealing surface.
2.
Tuck any strand loose ends back into the mesh channel.
3.
Verify the power supply cable is connected and cannot interfere with the sealing surfaces.
4.
Tighten the lid bolts gradually alternating diagonally opposite, to avoid undue stress or warp in the housing. Use a 13 mm
wrench.
5.
The lid bolts must be tightened to the specified 40 to 120 inch-pounds (in-lb) or 4.5 to 13.6 Nm to ensure proper closing.
The required torque is easily met using a 13 mm wrench but cannot be reached by using a nut driver.
En
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li
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