TD-23 V.23 Multidrop Modem
TD-23 is designed to satisfy industry's demands on reliability and functionality in environments with high levels of interference.TD-23 communicates via a 2- or 4-wire leased line according to the V.23 standard. Equipment with an RS-232 or RS-422/485 interface can be connected and communicate point-to-point or in a multidrop application.The modem is equipped with DIP-switches to set specific functions in hardware, for example, reception sensitivity, output signal level, etc. This is of particular importance as it allows each modem to be optimized according to the line quality. A general calculation allows 16 units over a distance of up to 25 km (15.5 miles). TD-23 is intended for mounting on a 35 mm DIN-rail, where the modem is attached and locked in a single action.


  • Data rate 1200 bit/s (V.23)
  • 2-wire (half duplex), 4-wire (full duplex)
  • Number of multidrop points, 16 (typical value)
  • Transmission distance up to 25 km (15.5 miles)
  • Adjustable output signal level
  • Adjustable reception sensitivity
  • Transient protection on the line side
  • AC-/DC-supply
  • Tri-Galvanic isolation (interface/line/supply)
  • Optional relay output reflecting the transmitter carrier

TD-23 Diagram