• The FOM-5S and FOM-6S, Fiber Optic Modems, are used for local data distribution, connecting full or half duplex synchronous computers and terminals. A pair of modems ensures integrity of data transmission over fiber optic cable at distances up to 3 km (2 miles).

• FOM-5S is a smaller version of FOM-6S, with all the same features. FOM-5S is 75 mm (3.0 in) by 18 mm (0.7 in); FOM-6S is 108 mm (4.3 in) by 24 mm (0.9 in).
  FOM-6S is normally provided in a plastic enclosure. It can optionally be supplied in a metal case to reduce radiated emission (see Ordering).

• A LED indicator indicates carrier detection on FOM-5S and FOM-6S models that are enclosed in a plastic case.

• Transmit timing can be provided by three alternative sources:

• Internal oscillator
• External clock from the DTE via pin 24
• Loopback clock derived from the receive signal.

• The carrier can be strapped for either continuous or switched operation, controlled by the RTS signal for transfer of a control signal end-to-end.

• The delay between Request to Send and Clear to Send can be set for either 7 or 53 msec.

• Innovative circuitry allows FOM-5S and FOM-6S to operate without connection to the mains supply, by using ultra low power from the data and control signals.

• FOM-5S and FOM-6S incorporate all the advantages of a fiber optic system, providing:

• Lower attenuation than with copper wire
• EMI/RFI and noise immunity, saving the cost of expensive and heavy shielding and complex error checking routines
• Almost absolute security and reduction in the cost of data encryption
• Negligible power radiation from the fiber makes eavesdropping virtually impossible
• Safety and electrical isolation: no spark hazard and no ground-loop noise problems.

Note: Attenuation is unrelated to frequency.

SPECIFICATIONS

• Synchronous transmission up to 19.2 kbps
• Transmission range up to 3 km (2 miles) regardless of data rate
• Full or half duplex
• Transfers one control signal end-to-end
• No external power required
• Plugs directly into the V.24/RS-232-C terminal connector
• Compact, lightweight, easy to install
• LED indicator for carrier detect

FOM-5S/*/+

Synchronous Fiber Optic Modem
(Sub-miniature)

FOM-6S/*/#/+

Synchronous Fiber Optic Modem
(Miniature)

ORDERING

FOM-5S/F/SMA
FOM-5S/F/ST
FOM-5S/M/SMA
FOM-5S/M/ST

FOM-6S/F
FOM-6S/F/ST
FOM-6S/F/W
FOM-6S/F/W/SC
FOM-6S/F/W/ST
FOM-6S/M
FOM-6S/M/ST

 
APPLICATION

A pair of FOM-5S or FOM-6S modems ensures secure
data transmission over fiber optic cable at distances up to 3 km (2 miles).