This is a simple battery holder for a pointer style ELT practice beacon. These are used for Search and Rescue training. The unit uses 5 C-batteries that only fit into the case in a pentagonal arrangement. This holder with identical top and bottom allows for the easy replacement of batteries in the unit without having to build a special battery pack or substitute smaller batteries. Print two and wire as per the diagram.

Wiring the battery holder

The holder top and bottom are identical. There is a small tab on one of the cell spaces for alignment. Make sure the tab on the top and bottom holder are on the same battery. You can use paperclip or wires to connect the cell spaces top and bottom. The batteries should go in with + - + - + facing up. The positive lead should attach to the top of the space with the tab. The negative lead should attach to the bottom of the space one counterclockwise of the tab when viewed from the top. I intended the slot to make the contacts more springy but it was not large enough for my printer to render it and it works just fine anyway.