Digi TransPort WR31 User Manual page 60

Hardware
9 SERIAL LED: Illuminates steady if a terminal is connected to the SERIAL port and the DTR signal
is on. Flashes when data is transmitted or received.
10 SIM / R-UIM Sockets (SIM card models only): SIM 1 and SIM 2 are for use with the Subscriber
Identification Module(s) (SIMs) or Removable User Identification Module(s) (R-UIMs).
11 Primary Wi-Fi antenna connector (Wi-Fi models only): This SMA connector connects the
router's primary Wi-Fi antenna.
12 Secondary Wi-Fi antenna connector (Wi-Fi models only): This SMA connector connects the
router's secondary Wi-Fi antenna.
Digi TransPort WR Routers User Guide
TransPort WR41 hardware
60