ASTRONEER

Once you find a gateway chamber, you need to power it up via the cable plug it has at the front. Use the terrain tool to build a ramp up to it if you're still on ground level.
On the first World, the gateway will need 5A of continuous power- although I note that the first one you find is much easier to unlock.

I crafted a small printer from my backpack and used that to create a platform. I hooked up the platform to the gateway and put on two small batteries I had found on debris. That supplied enough power to unlock the gateway.
Power cells will also work, as will power sources but note that if they don't supply enough power the chamber won't unlock, if the chamber is half open and power is lost then it will start to reset itself!


You already have the achievement once it opens but you can immediately use it to unlock another if you wish.
Use the odd stone to select a node to travel to and select one (origin node will always be unlocked as it is the gate you are using).