I hate to ask this, but are you sure the polarity of the battery was correct.
Actually, that's exactly what happens if you reverse the polarity of the battery in an RF-602 transmitter. I did it to "turn the battery off" and realized my mistake pretty damn fast when it started cooking itself. Luckily, I got the battery out in time and no damage done.
^^^^ quoting you guys again... i finally had free time again today to play... and the polarity must have been wrong the first time i put it in.
everything works super now. both my receivers and transmitter fire beautifully without any problems. I regret not getting an extra transmitter now to be able to fire remotely... might get one at some point.
My only complaint with these would be that I really wish they had put an "off" button on transmitter. but oh well, cant complain for the price if you ask me.