OK, in continuing my data collection journey, I need to switch from the RFM12 to the RFM69 get more range.
To this end I’ve build a clone of the EmonTH on breadboard using an Arduino Pro Mini, DS18B20 and RFM69CW.
I’ve programmed it, and it reads the temperature just fine (via the monitor), but I get nothing on EmonHub/EmonCMS.
After spending a couple more hours checking the code, triple checking the wiring etc, I swapped in a new RFM69CW, but this didn’t work either. Using another RFM12B (with alternate firmware obviously) works as expected.
Swapping back to the RFM69CW, I accidentally noticed that if I hold my finger on the antenna, it transmits as it expected and data shows up in EmonCMS.
And ideas what’s going on? The antenna is firmly soldered and the correct 82mm (for 868Mhz) length, with no loose connections.