*Note:  It may be blue indicator.  Upon power on, the blue light will be steady first.  After about 2 sec it will start flashing very fast.
If its not connected to the bluetooth headset, it will be blinking very fast, 2 pulse per sec.  
Bring the headset next to the transmitter can start pairing.  Once both the device are paired, it will blink very slowly, 1 pulse per 10 sec.