Using the KISS method here. 1 2500 A123, 2 leads, 1 lead to the RCVR through a switch, the other lead to ignition through a Rcexl opto switch controled by the RCVR. Been using it for a couple years now and at least 100 flights. No fuss, no muss, no problems, not even a hint of interference. Battle tested to the max on a high performance profile.