Model TC8518 
Fiber Optic Multiplexer
T1/E1, Data/Voice & Ethernet - Fiber Optic/OC3 Multiplexer



Features  Product or Application Questions (click here)

  • Multiplexes Up to 24 T1 or 20 E1 and 3 Ethernet Ports Over Fiber
  • Optional Voice (up to 8 channels FXS/FXO or 4 channels 2 Wire/4 Wire Analog) or Data (up to 8 channels RS-232/RS-422/RS-485)
  • Optical and Power Redundancy Standard
  • Key Features: Statistics Monitoring (T1/E1, Ethernet, Optics), Ethernet Rate Limiting, Remote Firmware Upgrade, Network Time Server (NTS), Temperature Monitoring and Loop Up/Down Codes
  • Management (Web, SNMP, Telnet, Console)
  • FXS/FXO Ports Support Modems & Faxes
  • High Temp (-20C to +70C) and Extreme Temp (-40C to +80C) Optional
  • Multimode or (1300nm) or Single Mode Optics (1300/1550nm) or OC3 Interface
  • 90-260VAC Hot Swappable Power Standard Optional Power: 12VDC, 24VDC, -48VDC, 125VDC


The model TC8518 High Capacity T1/E1 & Ethernet Multiplexer gives users the cost saving benefits of minimal hardware and fiber conserving efficiency along with a wide array of important features.  Key features include Web Management, Statistics Monitoring, Network Time Server (NTS), and the Extreme Temp version.

It multiplexes  4, 8, 16, 20**, or 24** T1 channels or 4, 8, 16 or 20* E1 channels and a 3 port Ethernet switch (combined bandwidth of 100Mbps) over multimode (1300nm) or single mode (1300/1550nm) fibers.  The Ethernet ports support non-blocking full 100Mbps total bandwidth.

Optional Voice (up to 8 channels FXS/FXO or 4 channels 2 Wire/4 Wire Analog) or Data (up to 8 channels RS-232/RS-422/RS-485)

Setup, diagnostics, and control are accessed via Web, Serial Console, Telnet or SNMP management. Diagnostics include LED indicators, dry contact alarms, and local and remote loop back to assist with troubleshooting and maintenance.  Statistics Monitoring keeps a history of all activity (optical, T1/E1, Ethernet).

VLAN, Statistics Monitoring, Remote Firmware Upgrades, Network Time Server, Temperature Monitoring, and Ethernet Rate Limiting features are standard.  The Ethernet switch is IEEE 802.3/802.3u/802.3x compliant and supports Huge Frames (1916 bytes). Each T1 or E1 channel is independent and transparent to the framing format and supports all applicable standards and line codes.

The TC8518 supports distances up to 100 km and offers a two-way "one fiber" WDM communication option to maximize fiber cable usage by transmitting and receiving data through a single fiber strand. The TC8518 also supports the OC3 interface. Redundant power and optics are standard, including automatic switchover for maximum reliability.

The TC8518 is available in 1U high Rack Mount. Fiber optic connectors are SC. Standard power is 100-240VAC; 24, -48, 125VDC power options are optional.  All power supplies are hot swappable.  For industrial environments, the High Temp Option (-20oC to +70oC) and Extreme Temp Option (-40oC to +80oC) are available. 


TC8518 Specifications

Data Rates
T1 1.544 Mbps
E1 2.048 Mbps
Ethernet 10/100 Mbps
Async RS232/422/485 Up to 115K
Audio 300Hz to 3.4Khz
Console Port Up to 9.6K
Channel Capacity
T1                          4, 8, 16, 20, or 24             
E1  8, 16, or 20
Ethernet  3 Port Switch
2/4 wire analog  Up to 4
RS232/422/485  Up to 4 or 8
FXS/FXO  Up to 4 or 8
Transmitter ELED/LASER*
Receiver PIN Diode
Wavelength 1300nm, 1550nm
Fiber Optic Connectors SC, ST
Loss Budget
1300nm MM
1300nm/1550nm SM

LED/ELED (62.5/125m): 15dB
LASER (9/125m): 20dB
Interface T1, E1 (G.703), IEEE 802.3, T1 (100 Ohm), E1 (120 Ohm)
T1 Connector (100 Ohm) RJ-48C (Female)
E1 Connector (120 Ohm) RJ-48C (Female)
E1 Connector (75 Ohm) BNC
10/100 Ethernet RJ45 (Female)
Phone, Analog, RS232/422/485 RJ11 (Female)
Console Port RJ45 (Female)

* Contact factory for higher requirements
** Future Release
Bit Error Rate 1 in 1010 or better
Dry Contact Normal Open
Visual Indicators
System LEDs PWR (Normal, Alarm)
Channel Status (each port) Unsync, Sync, Loopback
Optical Signal Status Unsync, SyncLB
Ethernet Link/Act, 10/100
Diagnostic Functions
Local and Remote Loopback
Standard 100-240VAC, 50/60Hz
Optional 24VDC, -48VDC
Power Consumption <30w
Operating 0 to 50C
Storage -40 to 90C
Humidity 95% non-condensing
Height (4.43 cm) 1.75"
Width (48 cm) 19"
Depth (16.57 cm) 6.5"
Weight (1.36 kg) 3 lbs.


Typical Application (Application Questions)

Typical applications include connecting T1/E1 signals from Cell Towers to Central Offices, linking multiple T1/E1 links between remote sites and adding Ethernet service to existing T1/E1 fiber optic links.

Service Providers use the TC8518 as an efficient, cost effective method to provide their customers with Ethernet (full 100 Mbps bandwidth
and can be rate limited in 32kbps increments) connections for data and T1 for voice.

The "two-way one fiber" option can double usage of existing fiber optic cable plants.

TC8518 - 4 to 24 Ch. T1/E1 & Ethernet Multiplexer