Questions on new Helix 5 gps di graph

I read to use sd card to install updates and register is this necessary? Also if I purchase a lake map card will it be useful without the link option on my Terrova trolling motor?

You do updates with SD card. To register all you have to do is go to Humminbird web site and have your ser num handy. Yes you can use a map card with out link and if your lakes are covered it is very helpful. So much so you will wonder how you got by without it. Remember this, your unit takes a micro SD card. When you buy one the micro will be in stalled in a full size adapter. Just remove the micro and installing unit. Don't loose the adapter incase you ever wanted to use in larger unit.

Thanks: I didn't want to buy stuff I don't need, I would like to see lake depths on map. And thinking the GPS will keep track of where my boat is, then I can fallow map on graph.

You can go to both Navionics and Lakemaster to see which lakes the cover in your area and find which chips they offer that are compatible with your unit. But if you fish one not cover you are still able to mark your waypoints.

I'll do some looking, I turned on unit and it showed my location, now to find a lake without ice.:fish

We don't have ice but the wind is killing us. Pre fished for tourney this weekend on Friday, 30-35 wind on small oxbow lake. Man it was rough. We are getting there though. Good luck with your unit. You will enjoy it.

Here is the link to the LakeMaster regions to see which region your lake would be included on ...
http://www.humminbird.com/Category/Support/Find-a-Lake/

Here is the Navionics webapp to see the detail on your lake ...
Navionics Webapp

Rickie