The June/July Midwest Edition of Game & Fish mag has a pretty good/thorough article on trolling to find main lake warmer weather into Fall, crappie. It repeatedly refers to having “higher end“ electronics to locate baitfish pods, and feeding/roving schools of crappie! Many of us “meat” fishers are lucky to have “something to fish from“, let alone “Guide Essential” electronics! My preference is a relatively inexpensive “Garmin Striker4“(cheap but many features incl. gps) to get me in the deeper(offshore) waters, (I have issues reading the very small screen in bright sunlight-and interpreting what’s on it!) So I rely on “my“ slow trolling methods once I feel I’m in the area/depth! where fish “could be“ located. I find over streambeds a good place to start. Using a couple rods with curly tailed grubs and different leads behind the boat, I can frequently locate a school of adequate size and numbers, mark the area with a waypoint or old school, “float/weight on a string”, go back close(but not on top of them) then work them over with long casts w/ jigs using different count-down sequences til I get their location dialed in. To constantly troll back and forth over them(as the article implied), imo is a recipe for disaster that will make them vacate the premises. Anyways, might be a good read for some post-spawn into summer crappie tips/incite.