Review sonar files on PC

Former Member
Former Member
Hello I'am new on this forum and today I have received Garmin echomap70s with black box module for sidevu/downvu.
I also have Humminbird 998c sonar with side scan /down scan..

I would like to know if there is some opensource software for garmin to display recorder sonar files?
Is there maybe a tool to convert garmin format to SON format?

thank you for any info
have a nice day
Peter