Async Fiber Optic Multipoint Modem

• Asynchronous transmission up to 38.4 kbps
• Multidrop operation over a fiber link
• Transmission range up to 46 km (28 miles) over single mode fiber
• RTS or data contention for multipoint operation
• Automatic disabling in the event of streaming

• Variety of optical options, including: multimode, single mode and laser diode for extended range make the unit suitable for any application

Long-distance connection to remote terminal units

The FOM-6MP async fiber optic modem operates over fiber to connect remote terminals and computers, connected in multidrop, to a central host. Transmission range (regardless of the data rate):

• 3.5 km (2 miles) using 850 nm multimode fiber
• 30 km (18 miles) using 1310 nm single mode fiber
• 46 km (28 miles) using 1310 nm laser diode single mode fiber

The FOM-6MP contains two optical interfaces and one V.24/RS-232 port. One optical interface passes data to and from the host while the other passes data to and from the rest of the terminals in the chain. The V.24/RS-232 interface is connected to the local terminal.

Terminal contention for transmission to the host is selectable: transmitting data or raising RTS signal.

The FOM-6MP includes anti-streaming protection which prevents blockage of data transmission. The FOM-6MP disables a port that blocks the polling for a preset, user-selectable period of time.

LED indicators help the user to easily isolate faulty segments along the chain of terminals. The FOM-6MP requires an external DC power supply of 10–30 VDC/500 mA.