You can record freely as you go about your day! For best sonar log recording, we suggest you keep your speed under 6 knots, although maximum logging speed may vary depending on which device you are using; perform a grid pattern where the distance between tracks is no more than 50 meters /150 feet; and save about every 30 minutes to reduce any risk of loss.
Make sure your CF card is inserted into your GPS chartplotter and press MENU.
Scroll to System Diagnostics... and press right arrow
Scroll to External Interfaces... and press right arrow
Scroll to NMEA0183... and press right arrow
Press Buffer... soft key (bottom of screen)
Press Record -> Start soft key.
You will need to press the soft key to “Start”, which will then move the highlight to “Stop”. This is now saving an active log to your CF card.
Plug the CF card out of your GPS chartplotter and plug it in your computer. If you want to know how to upload sonar logs from a Navionics Card, click here.