I recently purchased an older Vexilar FL-8. It came with a puck style transducer which is attached to an articulated arm. Does anyone know anything about these transducers and how they work through the ice?

just s good as the floting style, it is the same transducer, just has the wire coming out of the side instead of the top.

if there anyway to tell what degree the cone is they guy I bought it from did not know

I used the puck style transducer that came with my FL8 for several years and it worked OK. You need to mount a bull's eye bubble level on top so that you know you are pointing straight down for optimal response. It can be annoying to re-level every time you move if the arm doesn't hold position very well. I think that the puck is a 19 deg.

It should be in the plastic at the top of the 'ducer near where the cable enters. Look closely, sometimes it's really small...

-Munchy