ORIGINAL: Fredde1
but what is the difference betwene the reciver battery and the ignition battery?, the ignition box is in the front.
The ignition does not have a smooth current draw, it takes a big gulp of battery energy just after the spark fires. This impresses noise on the battery and lead equal to engine RPM.
Your dealing with micro volts of RF signal, give yourself all the edges you can. Cause if you keep cutting corners you will be shouting "I got hit."