Just found this in one of them folders that my computer hid from me. This may have been posted before. Can't remember. Maybe it is useful. I set my side scan 2X depth which is close to the chart.
http://www.bassfisher1.zoomshare.com...ngle_Chart.pdf
Member BS Pro-Staff and Billbob Pro-Staff
Proud Member of Team Geezer... authorized by: billbob and "G"
That chart's title says "Structure Scan" so I would assume that is Lowrance...
I thought Lowrance measured their beam angles at the -3db value...
Rickie
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