7
9.0 Forward Path Set-up :
(Refer to Figure 7)
LBN200 RFoG ONU
User Manual
1.
Using an optical power meter, measure the input optical power level at the fiber optic connector
coming into the node. The acceptable range is -8 to 0dBm.
2.
Clean and install the incoming fiber connector to the forward bulkhead.
3.
Using a DVM, measure and record the optical input power level at the electrical test point
(1V/mW). Verify optical input levels using Table 1.
4.
Using a CATV Signal level Meter, verify the RF output levels at the -20dB test point on
Output
1
.
5.
The Pad and Equalizer values are established by the use of JXP attenuators. The Equalizer
circuit is built on the board therefore choose a pad value to achieve your desired slope. (eg.
12dB attenuator in
EQ2
will result in a 12dB output tilt between 54 and 1000MHz).
6.
The LBN200 comes factory set with a
4dB
pad in
ATT1, 0dB
pad in
ATT2,
and
12dB
value in
EQ1
for optimum performance as per specifications. Verify and record your desired output level
and tilt. Attenuator values may be off
± 1db
to slight tolerance difference between units. Use
Step 4 to verify output set up.
7.
Plug in the desired Feeder Maker for the number of outputs required. Feeder Maker 100 is for
one output, 204 is for 2 outputs. While monitoring the forward
Out1
test point (-20dB), with a
4db pad in
ATT1
and with a 0dB pad in
ATT2
position, place the pad value corresponding to the
desired output tilt into
EQ2
. Continuing to monitor
Out1
test point (-20dB), adjust pad value in
ATT2
position for the desired output level. Verify that the level is correct at both ends of the
bandwidth spectrum. Output 1 & 2 are now set up in the Forward Path.
Table 1
LBN200 April 2013_rev1
Optical Level
(dBm)
1V/mW Test point
(± 20%)
-8.0
0.16
-7.5
0.18
-7.0
0.20
-6.5
0.22
-6.0
0.25
-5.5
0.28
-5.0
0.31
-4.5
0.35
-4.0
0.40
-3.5
0.44
-3.0
0.50
-2.5
0.56
-2.0
0.63
-1.5
0.70
-1.0
0.78
-0.5
0.88
0.0
1.00
