Hardware
Top view
Bottom view
X1
- GSM Antenna SMA female connector
X2
- Push-push SIM holder
X3-1
- Power connector 5.5/2.1 (+ centre), 5VDC stabilized power supply
X3-2
- Plugin Terminal Connector for digital input
X9
- Socket for RF transmitter module
1 - +5VDC (left)
2 – GND
3 – Transmit data
4 – Not used