Model TC1705

Universal Sync/Async Fiber Optic Modem
RS-232, RS-422, RS-485 (2-wire or 4-wire), RS-530, V.35 and TTL

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  • Data Rates up to 256Kbps
  • Distances Up to 80km* 
  • All Popular Electrical Interfaces
  • Built-In Test Signal Generator
  • Local & Remote Loopback
  • Interchangeable Interface
  • Supports 5 RS-232 Control Signals
  • Multimode & Single Mode Mode (850/1300/1550nm)
  • Built-In Power Redundancy
  • Local Dry Contact Alarm Relay
  • Standalone/Wallmount or Rackmount
  • High Temperature (-20C to 70C & -40 to 80C) Versions Optional


                TC1705 Stand Alone


The TC1705 is the ultimate "configure-it-as-you-need-it" fiber optic modem.  Ideal for applications requiring multiple interfaces, high data rates or full handshaking, it supports synchronous and asynchronous data rates up to 256Kbps.

It supports most popular electrical interfaces including RS-232, RS-422, RS-485 (2-wire or 4-wire), RS-530, V.35 and TTL.  Electrical interfaces are modular and can be easily changed before or after installation.

Distances up to 80km* are possible depending on various factors including electrical interface, optical transmitter, number of fiber optic connectors and fiber type and quality.  Power redundancy is standard. Optical redundancy is optional.

Diagnostics are extensive and include a built-in Test Signal Generator, local & remote loopback tests and LEDs for Power, Alarm, Tx, Rx and all applicable control signals.  The Test Signal Generator verifies both device and fiber optic link operation.  

Available for multimode (850/1300nm) or single mode (1300/1550nm), the TC1705 is compatible with all popular sizes and types of fiber optic cable.  Fiber optic connectors are ST or FC.  Electrical connectors are DB25 female.  Power is standard 12VDC, optional 24VDC, -48VDC, 125VDC or 115/230VAC with an external power cube. 

The TC1705 is available in two versions: TC1705R Rackmount Card for installation in a 19" rack assembly (TCRM192 or TCRM196) or TC1705S Standalone version.  Standalone or rackmount versions can be mixed or matched on either end.  There are two optional versions (Model TC1705T)  for extreme temperature applications (-20 to 70C & -40 to 80C).

*Contact factory for higher requirements (Laser version).

TC1705 Specifications    

Data Rates
RS-232 (Async with RTS, CTS, DCD) up to 128 Kbps
RS-232 (Sync) up to 128 Kbps
RS-422/530, RS-485, TTL (Async) up to 256 Kbps
RS-422/530, V.35 (Sync) up to 256 Kbps
Transmitter ELED, ELED, LASER*
Receiver PIN Diode
Wavelength 850nm, 1300nm Multimode
1300nm, 1550nm Single Mode
Fiber Optic Connectors ST, FC or SC
Loss Budget*
(850nm, 1300nm, 1550nm)
Multimode (62.5/125m): 15dB
Single Mode (9/125m): 20dB
Connector DB25 Female
Interface RS-232, RS-422/RS-530, V.35, or TTL
Bit Error Rate 1 in 109 or better
Dry Contact Normal Open

* Contact factory for higher requirements
Visual Indicators
System Status Status, PWR A, PWR B, Vcc, ALARM, ST, SLAVE
Electrical Signal Status RD, RT, CTS, SD, TT, RTS
Optical Signal Status TX, RX
Diagnostic Function Local Loopback Test
Standard 12VDC @ 500mA
Optional 24VDC, -48VDC, or 115/230VAC (with external power cube)
Operating -10 to 50C
Hi-Temp1 (optional) -20 to 70C
Hi-Temp2 (optional) -40 to 80C
Storage -40 to 90C
Humidity 95% non-condensing
Physical (Standalone/Wall Mount Unit)
Height (3.53 cm) 1.4"
Width (18.14 cm) 7.1"
Depth (16.57 cm) 6.5"
Weight (192 gm) 5.44 oz


The TC1705 Multi-Interface Fiber Optic Modem is intended for applications requiring high data rates and handshaking.