Thanks Joe - greatly appreciated.
I have hacked together simple Gateway / Node example codes for testing the ListenMode at low baud rates and I can claim some (very) modest success. I’m using Moteino R4s with the wire monopole antenna at 433Mhz. My test environment is urban, which includes a site with concrete and brick buildings in the way – as well as plenty of cars, trees etc...
Couple of points:
I tested using Felix’s 19.2K library
https://lowpowerlab.com/forum/moteino/long-range-low-bitrate-library-config/msg1137/#msg1137with a slight modification to the default Rx time – increasing it from 256us to 512us as follows (RFM69.h).
// By default, receive for 256uS in listen mode and idle for ~1s
#define DEFAULT_LISTEN_RX_US 512
The results were pretty poor.
I then modified the setup() code using Steinarrr’s 1200bps example tx as shown here:
https://lowpowerlab.com/forum/moteino/multistorey-indoor-range-performance-1-75km-range-(solution)/msg3189/#msg3189(Joe (if you’re reading) I believe Steinrrr’s code turns off the AGC – as you suggested.)
My code uses multiple attempts at the gateway to connect to the sleeping node, and I’m finding pretty reliable contact up to about 150 metres at 1200bps(I get no more than 50 metres at 19.2k).
But if I use a simple struct / send type of code (no ListenMode) I get a range of well over 500 metres using the 1200bps code – infact I got one transmission closer to 1 km!
OK – while there’s plenty I don’t understand about this, the main thing that bugs me is the range. If I understand it right, the node (radio) sleeps for 1 second – wakes up (for 512uS in my case) checks for incoming and if correctly addressed, then wakes up the microcontroller and does stuff.
So what’s the difference in range about? If the signal strength is good at 500 metres, why doesn’t it work at greater than 150 metres in ListenMode?
If anyone’s interested in seeing the code, I have it attached – it’s setup for a gateway and 2 nodes – but you can increase the number of nodes by changing a line of code in the gateway sketch – it’s commented.
Hope some of you gurus can shed some light on this. For my purposes 150 metres is OK – but it would be good to improve on it.
All the best,
Chris