Humminbird 859 Depth Trouble

Plenty of reading

http://www.crappie.com/crappie/fishi...ci-hd-di-help/

Awesome advice! I now have to learn how to upgrade the newer software, which I need to learn how to do. Hard for me to learn about technology, but if Im going to use it I need to learn everything about it. Thankyou for your time in research and knowlede sir, and if ya come across anything else you can teach me, or tips please keep the info coming!