Helix 9/10/12 gen 1 or 2 will network with Helix 7 g2n, any other Helix 9/10/12 gen 1 or 2, and minn kota iLink. Helix 5/7 gen 1 or g2 will not network with anything.
What he said.
I’ve got a gen 1 helix 12 hooked up to my 9 up front no problem. Only problem is none of them can share lake maps so you need a chip in each unit. I think that’s even the same in the g2 units. Not sure if the 7 will link up
On the helix series you can share waypoints and transducers between units but not maps. In order to get that capability you will need to go to the Solix series.