Radarange is the name Amana has given to its line of microwave ovens, and you will likely need to change the light bulb sometime over the lifespan of the microwave. It just takes a few minutes, and, after changing the bulb, you can once again watch your popcorn popping with a brightly lit Amana Radarange microwave interior.
Unplug the microwave.
Open the back panel on the microwave by unscrewing the nuts with the 1/4" socket.
Remove the nut on the lamp cover inside the microwave.
Remove the old light bulb, and screw in the new bulb.
Replace the lamp cover, screwing the nut back in. Then put the back panel onto the microwave and reattach the nuts that held it in place.
Plug the microwave back in and it will be ready for use.