O p e r a t i o n

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SG2 - EIFPT Optical Transmitter

The SG2-EIFPT is an enhanced, isolated, Fabry-Perot return-path optical transmitter designed for use in the SG 2000 node platform. It has a nominal optical output power of 1 mW and can be used in conjunction with an AM-RPR, AM-OMNI-RPR/2, or other similar return path optical receiver. Figure 5-20 illustrates the SG2-EIFPT:

Figure 5-20

SG2-EIFPT

 

SG2000

 

 

 

 

Transmitter

 

 

RF

(

 

 

 

INPUT

 

 

SG2-EIFPT

 

LASER

O

F

 

N

A

 

 

CURRENT

 

U

ASSEM BLED

 

(1 V/A)

 

L

IN MEXICO

 

 

 

T

 

Table 5-7 provides information on the user-related features of the SG2-EIFPT:

Table 5-7

SG2-EIFPT features

FeatureDescription

Optical power test point This test point enables monitoring of the optical output level of the module. The nominal scale factor is 1.0 V/mW. The optical power test point voltage is between 0.945 V and 1.055 V (optical power of 0.945 mW through 1.055 mW) when the module is enabled under normal operating conditions. Note that the optical power test point does not track changes in optical power due to the laser tracking error.

Laser current test point This test point enables monitoring of the current drawn by the laser diode. The nominal scale factor is 1.0 V/A. The laser current test point voltage is between 4 mV through 90 mV (laser current of

4 mA through 90 mA) when the module is enabled under normal operating conditions. The laser current is expected to vary widely with changes in temperature, but should always remain between the limits.

Transmitter enable

A green LED that provides visual indication of the transmitter’s

 

enable status.

Fault indicator

A single red LED that lights when the hybrid current is outside the

 

normal operating range, the laser output power is below normal

 

limits, or the laser current is above normal limits. Because the laser

 

output requires a short period of time to stabilize, it is acceptable

 

for the fault indicator to illuminate during the stabilization interval

 

(approximately 2 seconds). Note that the module must be enabled

 

for the fault indicator to function.

SG 2000 Installation and O peration Manual

Page 83
Image 83
Motorola SG 2000 operation manual SG2 Eifpt Optical Transmitter, SG2-EIFPT features