Easy to use
DIP switch for disconnecting and connecting signal (easy to connect external cables/props)
Branch too high signal
Red for low signal
RS232 8 signals DCD, RXD, TXD,, DTR, DSR, RTS, CTS, RI.

Loopback testare för RS232 med DB9 honkontakt

RS232 signal tester
DB9 male/female connector
Tests: DCD, RXD, TXD, DTR, GND, DSR, RTS, CTS and RI
Standard RS232 DTE and DCE connection
Does not require power supply