NickD - 11/3/2017 6:21 AM
1 cable and 2 dongles
(one for each unit
). That appears to be the right part number but the description is odd. Here is the part from the bird website.
https://www.humminbird.com/Products/AS-EC-QDE/
With one SI and a plain unit you will only be able to share waypoints/temp and 2D sonar. Their model is SI can only be shared between SI units and DI can shared between DI units or SI units. Compatibility matrix below.
https://www.humminbird.com/Category/Support/FAQ/EthernetSonarSharing...
If you decide to add the link to your Terrova you will also need to add an Ethernet switch.
If you want full sonar sharing get 2SI units and it gives you a better backup. But that is a finance decision for you.
Waypoint sharing is very handy but be aware the unit "owning" the waypoint needs to be powered on for the waypoints to be shared. I try to get the points uploaded regularly and moved on to both units.