Actually, with JR, the buddy box is required to have a battery, but DO NOT TURN IT ON. When you plug a trainer cord into a JR radio, it will turn itself on automatically, but will only be drawing a fraction of the current, because it is not actually broadcasting a signal. The master JR radio will broadcast the signal, and so will need to be turned on, and will draw normal current from the battery. Again, the JR buddy box does need a battery, and it does need to be charged, but do not actually turn on the buddy box, it will power up itself when the trainer cord is plugged in. You can remove the crystal and antennae from the buddy box, but leave the battery in. Again, this is just if you have JR--I'm not sure about airtronics. What brand of radio do you have?