Robomotic's Lab

Hello guys,

this is fantastic my rfm12b pcb antenna works pretty well, although I didn't measure the sensitivity/power but I got a very good range in my flat.

The benchmark necessary to compare the whip antenna vs the chip antenna is to measure the RSSI or the ARSSI at the receiver side. So basically having a whip transmitter (i.e. a jeenode), a chip transmitter (mine) and 1 jeenode receiver. Then measure the RSSI or ARSSI at the receiver side and compute the percentage of received power considering the same distance.

I can't wait for that, but in the meanwhile enjoy my little victory.

The RSSI value is provided digitally by the RFM module but is a 1 bit flag that tells you if the received power is greater then a specified threshold. A simple code to use is here.

The ARSSI is analog and provides of course a better measurement but I need to probe a pin on the board which is not exposed as described here.