When using one on a boat,how does it work? When you find fish do you have to mark it with a buoy and then move to  cast at that spot or do you just fish straight down off the side of the boat.

How would I be able to rig one on my JonBoat? I understand theres a transducer thats mounts somewhere to look at the structure on the bottom of the body of water your fishing. Where would it mount? Anyone ever use a depth/fish finder on thier jon boat?

yes, you can mount one on your jon boat.  the easiest thing is to mount the transducer on the trolling motor.  then mount the graph onto a board or directly to the boat.  you don't have to drop a bouy or fish right off the side.  what you want to do is graph an area of the water that looks like i might hold bass...whether it be structure or cover.  if you notice something, just look around you at the bank.  pick out a tree or bush or whatever and visually mark it.  look at how far from the bank you are and what not.  then back out an fish it.

now, if you're on a huge lake and out in the middle of nowhere, then yes, mark it with a bouy.  if you're fishing a drop off, it migt help to mark the top, middle, and bottom of the drop to help you in placing your bait in the right spots.

Jason

NEBassMan is correct about mounting the transducer on your trolling motor being easier to install. If a trolling motor is the only mode of propulsion but if you have an outboard you will only be able to use you finder if the trolling motor is in the water. Solution mount the transducer on the transom, mount the finder on the bow, go to the setup screen of the finder and change the font size till you can see it from where you drive.

Tommy T.

The very first thing you need to learn about using one is not to consider it a "FISH FINDER".  99% of the fish you catch, you will never see on the thing.

It's #1 purpose is to find structure and underwater cover that has the potential to hold fish.  You have to know or figure out what fish are holding on/around, what depth, and where (points, creek channels back of coves, steep drops etc).

About the only time you can cosider them fish finders is when fishing strippers in deep water, schools of crappy in deep water or using it to locate shools of shad.   The trick with the shad is find where and about what depth the shad are running, and then look for points or channel drops at that depth the shad are intersecting with.  The bass will be normally be holding on/near the bottom at these locations.  usually just next to some cover or just down in the drop from the edge of it.   Seldom will they show up on your graph.  Sometimes, you can find them suspended off the bottom over deeper water in what I call wolfe packs.  If deep, jigging shade colored tube worms can produce some of the best fishing you could want when you find them, or if shallow enough to ge a crank bait down to them can produce some good fishing also.