CANOGA PERKINS 2240 Fiber Optic Modem - Manual (Page 22)

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Canoga Perkins
2.2 Setup
The setting up of the 2240 Modem includes the two-section HI / LO optic power
switch, internal control switches and the signal ground strap. The setup, as described
in the following sections, provides the initial configurations for operation of the unit.
2.2.1 HI / LO Optic Power Switch
All versions, except for ELED and LP Lasers models, incorporate an optic power level
dual DIP switch for varying the transmit power of the fiber optic LED or Laser (see
Figure 2-1). Both sections of the switch must be set the same. The switch for the 2240
standalone is located on the rear panel of its enclosure. (The switch for the 2240 Rack
Chassis is located at the rear of the PC card, adjacent to the transmit optical connector.)
The optical power switch provides two settings for optical transmission level. The
appropriate switch setting depends on the loss of the fiber optic link. Each optical
model has a different transition point in terms of loss. Refer to Table 2-A for the link
loss ranges for each optical model.
For example, if the 850nm model is used and the link loss is 5 dB, use the LO setting
on that line.
Table 2-A.
Link Loss Range
NOTE: The 1310nm LP Laser does not have a HI / LO power switch.
Link Loss Range
Model HI Power LO Power
850nm Standard >6 dB to Max <6 dB
1310nm HP Laser >6 dB to Max <6 dB
1550nm HP Laser >6 dB to Max <6 dB
1310nm LP Laser – –