'38'Cable brakes with 'Floaters'

[39DLXE]

Hello again:
Thought it would be best to start a new thread RE: cable brakes.
I know '37 and '38s have cable brakes, but have also heard 'cable brakes in conjuction w/ 'floaters', and kept well adjusted can function almost as well as 'juice' (my 39) brakes'.
Would probly like to keep original cable brakes, but not familiar with the term 'Floaters' and what their function is. Can any shed any light on this? would be much appreciated.
thanks,
John