1, Connect in series with any RS-232 interface for testing a serial RS-232 data link. Simple and easy, no oscilloscope is needed. DIP switch can setting disconnect or reconnect any signal, and support external probe test signal from male or female position.
2, 8 double-color (red and green) LEDs indicate the logic states for respective data lines. Green for logic HIGH and red for logic LOW. Full RS232 spec compliant with LEDs for all 8 signals: DCD, RXD, TXD, DTR, DSR, RTS, CTS, RI.
3, No external power required. No driver required. Plug and play. Jack sockets(nuts) on the tester can be unscrewed easily(with metal shell held in place) if needed to mate with another connector that has jack sockets.
4, OS Compatibility: Windows 98, Me, XP, 2000, 2003, CE, Vista, Windows 7, and Windows 8 as well as Linux and Mac OS 10.X, ect.
5, Typical application scenarios: Watching the TXD and RXD LEDs either changing states or flashing to know data transferring direction: from machine to computer or from computer to machine. Verifying TXD/RXD wires should be wired crossed(swap pin2 and 3) or straight through by observing TXD and RXD LEDs at a rest state. Verifying it is a DTE or DCE device (and whether you need a null modem or not). Verifying whether modem controls are active, even if they're not being asserted. Testing control signal between control systems (AMX, Crestron, etc) and the devices they control. Determining if the serial connection is mated properly and if communications is occurring. Whether the wall control or the projector is malfunctioning.