The most important consideration in planning the fiber optic link is the “power budget” of the fiber modem. This value represents the amount of loss in dB that can be present in the link between the two modems before the units fail to perform properly. This value includes line attenuation as well as connector loss. For the FOSTCDR the typical connector to connector power budget is 12.1 dB. Because 62.5/125 μm cable typically has a line attenuation of 3 dB per Km at 820 nm, the 12.1 dB power budget translates into 2.5 miles. This assumes no extra connectors or splices in the link. Each extra connection would typically add 0.5 dB of loss, reducing the possible distance by 166 m (547 ft.). The actual loss should be measured before assuming distances.
Figure 2: Typical Setups
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Dip-Switch Setup
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SW1:6 = ON | FOSTCDR |
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SLAVE
TX | RX |
SW1:6 = ON | FOSTCDR |
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SLAVE
TX | RX |
SW1:6 = ON | FOSTCDR |
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The
FOSTCDR2999 Manual | 3 |
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph