RAD section home tab  Search for RAD equipment  RAD and other WAN / LAN specials  Request a quote on RAD or other WAN / LAN equip.

RAD FOM Fiber Optic Modem Section

FOMi-T3 is an intelligent T3 fiber optic modem

FOMi-T3 is an intelligent T3 fiber optic modem designed for the transparent transmission of T3 or HSSI signals over multimode and single mode fiber optic cables. FOMi-T3 intelligent T3 fiber optic modem operates with a wide range of fiber optic interfaces over multimode and single mode fiber optic cables (see Table 1). The modems T3 electrical interfaces are available with a station clock module that  allows them to be synchronized with a central system clock. The station clock T1 input is 1.544 Mbps. FOMi-T3 intelligent T3 fiber optic modem operation complies with ITU-T G.703, G.921 and G.956 requirements.

Key points for the FOMi-T3 intelligent T3 fiber optic modem from RAD:
- Fiber optic modems, extending the range of T3 or HSSI services over fiber optic cables for up to 110 km (68 miles)
- Transparent to T3 and HSSI framing
- Support a wide range of fiber optic interfaces, including long-haul and WDM options
- Fiber optic redundancy for better service availability
- Operate opposite RAD's Optimux-T3 multiplexers (data only)
- Managed by an ASCII terminal or an SNMP management station
- Support different clock modes, including a station clock
- Relay minor and major alarms
- Include redundant power supplies (optional)
- Available as single modem cards for RADs LRS-24, modem rack with SNMP management (except for HSSI option)

Two models are available for the FOMi-T3 intelligent T3 fiber optic modem:
FOMi-T3 with T3 interface that operates with 44.736 Mbps internal clock and utilizes B3ZS coding
FOMi-T3/HSSI uses T3 internal clock and operates at 44.736, 22.368, 11.184 Mbps data rates.
FOMi-T3/HSSI contain an HSSI interface card that acts as an ECL/TTL transceiver and as a DCE interface. These modems do not 
support the station clock option. 

FOMi-T3 intelligent T3 fiber optic modem supports a wide range of optical interfaces that operate at various wavelengths over single 
mode and multimode cables. They also support a variety of physical connectors (ST, FC/PC and SC), as detailed in Table 1. A dual 
fiber optic interface allows full redundancy on the fiber optic transmission. A switchover mechanism is activated immediately upon 
detection of low optical levels on one of the dual optical links. 

FOMi-T3 operates opposite RADs Optimux-T3 which integrates up to 28 T1, 21 E1, or any combination of T1 and E1 channels, over a 
single 45 Mbps data stream.

FOMi-T3 intelligent T3 fiber optic modems can be managed using an inband channel over the fiber link. The management channel
operation does not interfere with the data transmission.
Available also as single modem cards for RADs LRS-24, 19-inch SNMP-managed modem rack. LRS-24 accommodates up to ten 
modem cards without redundant fiber link. If the modems have a redundant fiber optic link, the maximum number of cards is seven.
The modem cards and attached remote FOMi-T3 intelligent T3 fiber optic modems units can be managed via RADview, RAD's SNMP 
network management system. The standalone units are also managed via an ASCII terminal.
FOMi-T3 is an intelligent T3 fiber optic modem
DTE INTERFACES of the FOMi-T3 intelligent T3 fiber optic modem
Data Rates
- T3: 44.736 Mbps
- HSSI-T3: 11.184, 22.368 or 44.736 Mbps
Line Codes
T3: B3ZS
T3: 75Ω, unbalanced
HSSI: 110Ω
T3: According to ITU-T Rec. G.703
HSSI: 2m (6.5 feet), nominal
T3: Two shielded BNC
connectors (unbalanced)

Applicable Standard
ITU-T Rec. G.956
Line Code
Specifications and Ranges
See Table 1
Redundancy options
Additional link is optional

Input Data Rate: T1: 1.544 Mbps
Line Code: AMI or Square
Impedance: 75Ω, unbalanced
Two shielded BNC

FOMi-T3 intelligent T3 fiber optic modem General information
Loopbacks: Local analog (LLB), Remote digital (RLB), Local digital loopback (DIG), Dual LLB+DIG (DLB) Router loopback (LC), for 
units with HSSI interface only
Statistics collection:
BPV (electrical), LCE (fiber optic), PSES (electrical and fiber optic), UAS (electrical and fiber optic)
Control Port: V.24 (RS-232) DTE, operating at 9.6 kbps to 115.2 kbps, Control Port Connector D-type, 9-pin, female
Alarm Relay Port
Dry contact via 9-pin, D-type, female connector. Operates as Normally Open and Normally Closed, using different pins.

AC: 100 to 240 VAC (10%), 47 to 63 Hz
DC: 24 VDC (10%) or
-48 VDC (10%)
Number of Power Supplies
One or two (power sharing)
Power Consumption
15W maximum (for one or two power supplies) 

Physical- Height: 44.0 mm / 1.7 in, Width: 426.8 mm / 16.8 in, Depth: 258.0 mm / 10.5 in, Weight 2.5 kg / 5.5 lb

Temperature: 050C/32122F
Humidity: Up to 90%,

Ordering Options:
FOMi-T3/*/#/$/^ T3 and HSSI manageable fiber optic modem
FOMi-T3CF/#/$/& T3 manageable fiber optic modem card for LRS-24 ETSI version
FOMi-T3CB/#/$/& T3 manageable fiber optic modem card for LRS-24 ANSI version

* Specify power supply:
AC for 110230 VAC
ACR for redundant 110230 VAC
24 for 24 VDC
24R for redundant 24 VDC
48 for -48 VDC
48R for redundant -48 VDC

# Specify fiber optic interface type
(# for connector type, followed
by & for optical wavelength):
ST for ST type connector
SC for SC type connector
FC for FC/PC type connector

& 85 for 850 nm, multimode, VCSEL
13MM for 1310 nm, multimode, LED
13L for 1310 nm, single mode, laser diode
13LH for 1310 nm, single mode, long haul laser diode
15L for 1550 nm, single mode, laser diode
15LH for 1550 nm, single mode, long haul laser diode
SF1 for 1310 nm transmit and 1550 nm receive
SF2 for 1550 nm transmit and 1310 nm receive
Note: For single fiber connection (WDM) one of the devices must be ordered with an SF1 interface and the other with an SF2 

$ Specify R for redundant fiber optic link (see # and &, above, for options)
^ Specify station clock or HSSI: STC for station clock (not available for units with HSSI interface) HSSI for HSSI (standalone units 

FOMi-T3 intelligent T3 fiber optic modem data sheet (pdf)

Some of the most popular models are: 


Immediate price quote - Call 727-398-5252 or e-mail cs@bestdatasource.com

Don't forget to ask about  RADCare support for your RAD products.

Other RAD sections of interest:
RAD Accessories, RAD ATM products, RAD Baseband modems and last mile access, RAD Cables & Misc, RAD Digital Service Access Devices ( FCD ), RAD Fiber Optic modems and Converters, RAD IP and Ethernet Access, RAD Kilomux Data, Voice, Fax and LAN integrating Multiplexers, RAD LRS Modem rackRAD MegaplexRAD Networks Management, RAD Optimux Fiber MultiplexersRAD Sharing Devices, RAD Short Range ModemsRAD T1/E1 Digital Cross Connects ( DACS ), RAD T1/E1 Digital Cross Connect (DACS) for single E1 / T1 applications, RAD TDMoIP, RAD Voice Interface Converters, RAD Voice Trunking Gateway

Specials   E-mail us   Bookmark this site   More RAD    Download RAD English catalog    Important Notices

Use Visa to purchase Data Communications Equipment    Use MasterCard to purchase Data Communications Equipment
E-mail: Webmaster about the RAD portion this site.
Last modified: January 17, 2015
1998-2017 Cutter Networks Inc - All rights reserved