> Sending a wake call to come out of low power states is what the old "Morse code" audible pulses of interference on radio in the GSM days were doing kinda, bu

> Sending a wake call to come out of low power states is what the old "Morse code" audible pulses of interference on radio in the GSM days were doing kinda, but in this instance the radio in receive mode is quite expensive, something like 1-20ma. To get years long battery power you need micro amps.