I'm working on a DIY project built on the Moteino M0 + RFM69 consisting of a battery-powered receiver and a line-powered transmitter.
My goal is to reduce power consumption for the receiver to the absolute minimum while still allowing it to detect a transmitted signal within ~1 second. The transmitter is always-on with no power restrictions, and transmissions are rare (e.g. a few per day), so it can blast out and repeat a transmission until the receiver sends an ACK.
I understand that the RFM69 radio will always draw ~17mA when in receive mode, so I assume that any power reduction will come from minimizing its RX duty cycle. I read elsewhere on the form, for example, that the radio may only need ~250uS to reliably detected a transmission with a long enough preamble, however I'm not sure if that was verified or followed through with working code.
Does this come down to calling radio.receiveDone() once per second for as short a time a possible, or are there other tips/tricks/best practices here?