Since several people have had issues with turning on the map, it's not mandatory to turn on the power as you have the turbine to access things that require power. Turning on the power is more of a step for completing the Easter egg. Anyway, I’ll explain how to do that step:


1: At the entrance of the cemetery, there are some boxes and an axe stuck in the ground. Grab it, it's free, and you need to break some wooden planks that block a room in the spawn house with that axe.



2: There, you will find a part of the Wunderwaffe. The other parts can be found by opening areas



3: Once the Wunderwaffe is crafted, it must be fired at the top of three antennas scattered around the outskirts of the map. They are quite visible