I use the cheapest Canadian tire fishfinder avaialble( pirahna)
Had an Eagle fishfiner once. The rubber face stuck the buttons too often, so I switched. Get a spare. You can't often get them repaired in the tropics. Tape two 6 volt dry cells together and you can sound an entire area from your dinghy ,or scout out a pass before going thru.
The fuse kept getting disconnected, so I soldered wires onto the ends of a fuse. Contact guaranteed now.
Till the fuse blows and you have to get out the solder gun.
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