907-Fos (1X2 Smf/Mmf Fiber Optic Switch Card); Figure 6-8: 907-Fos, 1X2 Fiber Optic Switch Card - Focal 907 User Manual

907-0601-00 Rev. C
6.7

907-FOS (1x2 SMF/MMF Fiber Optic Switch Card)

Card P/N
Config. Dwg.
The 907-FOS card shown in Figure 6-8 is an optical switch card that can be manually or electrically switched
to choose one of two optical fiber inputs in redundant systems. Variations of this card include multimode and
singlemode options. The optical signal from either input F2 or input F3 is switched to a common output fiber,
F1, via toggle switch S1 or via a TTL-compatible signal at J2 connector. Typically the two input fibers are
connected through an umbilical and tether to a remote card with a splitter (907-SPLIT) or two separate remote
cards for optimal redundancy subsea.
When switch S1 is set to position 1, the switch is forced to the F2 input; when the switch S1 is set to position
2 or 3, the fiber switch is forced to the F3 input, but will be overridden by a digital signal at the J2 connector,
per the configuration drawing.
External LEDs can be directly driven via pins 1 and 2 of connector J2, corresponding to F3 and F2
respectively. These pins are pulled low (0V) when the LEDs are on and can be directly connected to the
cathode of external LEDs, where the anodes are connected to +5V. On board resistors limit the sink current
to 12mA when on. Refer to the configuration drawing. LEDs D1 and D3 are ON when the F2 path is selected,
and D2 and D4 are ON when the F3 path is selected.
The 907-FOS card can be powered with +5 VDC via the PC/104 backplane or via connector J2 (pin 4 = +5V
and pin 6 = GND). The card draws 70 to 90 mA, depending on the switch state – switch position 1 draws the
higher current.
Optical insertion loss is typically less than 1.0 dB per 907-FOS card.
Focal Technologies Corp.
907-0015-06 (SMF), 907-0015-50 (MMF)
907-2031-00

Figure 6-8: 907-FOS, 1x2 Fiber Optic Switch Card

Model 907 Video/Data Multiplexer – User's Guide
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