Here an unusual photocell. We don't know what it was used for. Maybe you do?
It is covered in parafin wax except for a small window over the photocell area.
It was made by Continental Electric and is marked XR-711-1. It is similar to a 917 photocell.
We were not able to measure any output, so it may not be working.
That's all we know about it. This item is sold as is.
