"Electrical" noise shows up on a screen as jittery pulsing bars.......means electrical interference from adjoining wires, non-insulated spark plugs/wires, transducer too close to engine etc.etc.etc. If you don't have that then it must be your settings probably. Half the fish I catch are never seen on the fishfinder. When I see a baitball, by the time I get turned around and set up for it, it's moved on or I can't find it again. I go more by local knowledge and looking at charts to see where fish could be holing up. Also go by time of day and what tide is doing. I read fish reports on fish sites like it's going out of style too. You can never get enough info. That said, most places the fish go the same place,same route ,same depth every year although there are exceptions now and again. The only thing I use my finder for is to know depth. Other than that I never look at it much. At times it will suddenly show me a lot of fish in a place and it will aso show the baitballs too. I can get an idea of how deep the fish are. But......you can' t tell exactly what the specie is by looking at a symbol on a finder. Could be dogfish,hake, pacific cod, coho, shakers etc.etc. Every year it's usually the same lures as always that catch salmon in a given area. Such things as leader length on a hoochy could spell the difference between success and failure. Such things as lure depth could make a difference. When you go fishing bring your "A" game....but if it doesn't work don't be afraid to try "B" game, "C' game and "D" game. Fishing isn't about luck or instinct.......it's about knowledge. If for example you read that right now the fish are 120ft down in 500ft of water in an area...and you are in that area on the right tide, then don't worry about marking fish and bait.....just put the gear down to 120ft-ish and start fishing. A lot of fish approach from beyond the scope of a fishfinder....so don't think you are going to see every single fish on it.... You can't possibly know where all the fish are all the time.....unless you are working as a "fleet" with other guys in other boats and you all have radios. It's a pretty big ocean out there. Read up on as much as you can about an area......even if you have to go back through the archives. Like I said, it's usually the same game basically every year but there are good years and bad years.