[psadri]

The cable could be replaced with a rotary switch with stops for each recipient. I’d also add a picture of each grandchild in addition to the name. But overall, this is an awesome idea :-)

[bredren]

I could see this, maybe each time the dial settles into its little ka-thunk index might also play “hello grandma” in the grandchild’s voice.

[askvictor]

Or a set of radio buttons (i.e. from an actual radio).

[psadri]

The old radio metaphor would work pretty well!