Can I make internal calls between my three Essential digital voice phones?
you need to change multo single in call mode page 24
I think @imjolly may have misunderstood your question.
Yes, you can make internal calls between handsets. No need to change any settings.
But how? There is no mention of this in the user manual, other than dialling the landline number so that the other phones ring. Then when answered a two way conversation is possible, but this comes out of the plan user minutes.
Doesn't anybody just play with devices to find the option. I had no idea whether you could make internal calls or not, 10 seconds of button pressing revealed that it is possible.
Press the green phone symbol then the right navigation to the last dot.