Instructions for using maps
Approach:
Download the map and extract the zip file to a PC.
The zip file contains one or more at5 files.
Place the at5 file (s) on an SD card. You can either put the map directly at the root of your card or in a separate folder. Suggestion: create a folder called "Thematic map C-Map EN-Y300" (if you have downloaded maps that are compatible with C-Map EN-Y300) and put the maps you download from this page there.
I do not recommend putting the at5 file on the same SD card as you have your C-Map card, although in theory this will work.
Insert the SD card into a free slot in your chartplotter.
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The first time you start your plotter with the new maps, all map layers will be displayed. If you have loaded several different theme maps, this will not be appropriate as several of the areas overlap.
To turn off different maps and / or map layers on Simrad NSS, select:
Menu
More options
Chart options
Categories
To turn off different maps and / or map layers on Lowrance HDS, select:
Menu
Chart options
View
Categories
You have now got a list showing a list of main categories available for the map you have active.
Example of main category with subcategories
If you have chosen to display the theme maps together with your C-Map map chip, there will be many categories here. If you have chosen to display the theme map together with maps downloaded from C-Map Genesis, there will be fewer categories. You will recognize your theme maps by the name of the categories. You can choose to beat a category at the top level, then all the map layers under this category will also be turned off. Alternatively, you can expand the category and select which subcategories you want visible in the map.
The chartplotter will remember these settings the next time you go on a trip as long as you do not remove the memory card and change the contents.