Have one on my Cascade 44.... I installed it and IT always works. Mounted on a pole on the aft starboard side and ran the cable to the helm
... remember I have an aft cockpit
The only way I know how to test one without all the test platform is to set it on a pedastal so that it is above your head
by a couple of feet, connect it up and turn it on. If you have an open area in one direction or another then you should be able to pick up some returns along the opening.
I think you can still get the manuals
in PDF on the web from Furuno. It is a 16 mile radar
but figuring the theoretical range of line of sight, 16 miles is plenty far.
I get a charge out of people that go for the longer range systems and mount them on their pleasure boat. Doesn't do much good. The newer ones have more electronics
to them that can do a better job of radar resolution.
If you need I can probably get more info on the unit from my boat that is on the hard