Electro Standards Laboratories DB9 Automatic Fallback A/B Switch Model 4126

The PathWay® Model 4126 DB9 Automatic Fallback A/B Switch with RS232 Remote allows the user the capability of sharing a single port interface device connected to the “COMMON” port among two other devices connected to the “A” and “B” ports, with remote access functionality The Model 4126 is packaged in a slim desktop style enclosure. The switch may be controlled locally by manually operating the front panel pushbutton or remotely from the DB9 female Serial Interface Remote port located on the rear of the unit. The front panel LED display indicates the switch position and unit power status, and mode of operation. The unit monitors data activity on both port “A” and “B”. If activity on the connected port is lost, and if the other port has established valid activity, the unit automatically switches to the port with activity. As long as there is activity on the present port, the unit will maintain the connection with the connected port. If neither port has activity, it will stay connected to the present port and continue to monitor for active data on both ports to switch to. FEATURES: • The switch ports are transparent to all data. • All (9) pins of the DB9 interface are switched via break-before make electromechanical relays. • The unit maintains last set position on power loss and continues to pass data. • Front panel pushbutton control (In manual mode). • Remote RS232 ASCII commands that allow the user to control switch position, lockout front panel operations, change modes, obtain switch status, as well as query fi rmware version number, query serial number and enable/disable auto-send of switch positions. • In Manual Mode, the unit does not switch between A and B unless commanded to do so via the front panel pushbutton or Remote commands. • In Auto Fallback Mode, automatically chooses its switch position based on signal presence • Signal Presence based on RS232 TD activity on pin 3 of ports A and B. • Two signal loss modes and eight delay times are settable via the Remote RS232 commands only. • Delay time selections are in one second increments from 1 second to 8 seconds. • Signal loss modes either Alternate or Maintain position on signal loss (only in automatic fallback mode). • Default settings are: Auto, Maintain, 2 second delay. • Front panel LED’s display present position and power status and operating mode.