hollow knock knock knock braking noise

Thanks. I put her away for the winter this weekend. I need to decide if I am finally going to convert it over to disks in the spring anyway. Honestly the power drums work fine so I will likely just open them up and look to see what's going on before I put it back on the road and stay with the drums. I also think that something had come loose in there (spring, shoe, etc)

It seems odd that there was no change in braking performance if something has let loose in there. I doesn't pull at all and brakes fine. It just makes the hollow knocking or tapping noise at the same rate the car is moving. Interval between knocks gets less frequent as car slows down. I will look for this thread and post an update in the spring. Hopefully it is a short off season this year.