what is the maximum loss allowed for a 1000base LX\LH GBIC?

[admin_2]

I AM RUNNING ABOUT 4800 FEET FROM MY 3508 TO A 3548 USING 1000BASE LX/LH SINGLE MODE FIBER. I NEED TO KNOW WHAT THE MAX LOSS IN Db WOULD BE, AS I AM GETTING A LINK LIGHT, ONLY TO LOSE IT IF THE FIBER JUMPER IS MOVED. I HAVE CHANGED THE JUMPER WITH A KNOWN GOOD ONE, AND STILL SEE THIS PROBLEM. PLEASE TELL ME WHAT THE ACCEPTABLE RANGE OF LOSS IN Db TO MAINTAIN A GOOD CONNECTION IS.

[#2]

The 1000BASE-LX/LH (long wavelength/long haul) GBIC interfaces fully comply with the IEEE 802.3z 1000BASE-LX standard. However, their higher optical quality allows them to reach 10 km over single-mode fiber (SMF) versus the 3.1 miles (5 km) specified in the standard.

Transmitter output power

(minimum/maximum)-3/-9.5 dBm

Receiver maximum input power

-3 dBm

Receiver sensitivity

-19 dBm

Channel insertion loss

50 micron MMF 4.4 dB

62.5 micron MMF 6 dB

9 micron SMF 6.5 dB

When using an LX/LH GBIC with a 62.5-micron diameter MMF, you must install a mode-conditioning patch cord (CAB-GELX-625 or equivalent) between the GBIC and the MMF cable on both the transmit and receive ends of the link in the following situations:

1.Less than 328 feet (100 meters). When illuminating short lengths of MMF with an LX/LH GBIC, the mode-conditioning patch cord reduces the amount of optical power coupled into the MMF. Excessive power can saturate the LX/LH receiver causing an elevated bit error rate (BER).

2.Greater than 984 feet (300 meters). When illuminating long lengths of MMF with an LX/LH GBIC, the mode-conditioning patch cord offsets the laser light to reduce the possibility of differential mode delay.