Designing and Expanding the Network 2 - 9
Table 2-5 provides information on the 10BASE-FB -specific optical power
budget.
Table 2-4. ONline 10BASE-FB Module Optical Po wer Budget:
High Power
Cable
Size
Used
(micron)
Transmit
Power
(dBm)
Receive
Power
(dBm)
Optical
Power
Budget
(dB)
Link Loss
Required
(dB)
(ONline to
ONline)
Link Loss
Required
(dB)
(ONline to
10BASE-F
B)
50/125
NA 0.20 -14.25 ±
2.25 -8.0 to
-30.0 13.5 None >2.0
62.5/125
NA
0.275
-10.0 ±
2.25 -8.0 to
-30.0 17.75 >0.25 >6.25
85/125
NA 0.29 -7.0 ±
2.25 -8.0 to
-30.0 20.75 >3.25 >9.25
100/140
NA 0.29 -4.5 ±
2.25 -8.0 to
-30.0 23.25 >5.75 >11.75
Table 2-5. 10BASE-FB Optical Power Budget
Cable Size Used
(micron)
Transmit
Power
(dBm)
Receive
Power
(dBm)
Optical
Power
Budget (dB)
50/125 (NA 0.20) -20.0 ± 1.0 -14.0 to 29.0 8.0
62.5/125(NA 0.275) -15.1 ± 1.0 -14.0 to 29.0 12.9
85/125 (NA 0.29) -13.1 ± 1.0 -14.0 to 29.0 14.9
100/140 (NA 0.29) -11.6 ± 1.0 -14.0 to 29.0 16.4