This stream archive runs about 68 minutes and opens on a card reading "Stream Archive" and "Smart Railroad Intersection", with no episode number, so the number here comes from the playlist. Most of it happens in Basket's creative test world, on a flat stretch of sand, where Basket works out the redstone for the intersections that will sit all over the rail network. The last ten minutes are back on the Hypermine server, where Kondrik says hello in the chat.
A roundabout on top
The shape on top comes from a design a viewer shared. Basket likes it: four double lines meet at a little roundabout around an open 5x5 middle. That open middle is handy, because a ladder can go down through it to the machinery below.
Trains keep to the right ("because I'm an American"), and the whole thing rests in one state: whichever way a train comes in, if nothing changes, it turns right. So only two choices need any redstone. Going straight flips one track. Going left flips two. Basket sets the resting states with torch pillars and drops a little marker to keep track of which way is north.
Floors of redstone
Underneath, Basket stacks four floors, and each one takes a signal from a different direction. Instead of doubling up torches to flip a signal, the floor a line lands on does the flipping. Repeaters go in all over the place so signals don't bleed back up into the wrong floor. It gets crowded fast. "I should have built this a little higher up," Basket says, more than once, but the test world stays mod free.
The reason for building down instead of out is the neighbors. On the server, the ground beside a track might be someone else's build, so everything has to fit under the rail's own footprint. When the wiring is done, Basket plans a trapdoor and ladder from the top and a walkway on each floor, so any part can be reached for repairs.
Tokens in, tokens out
Each intersection gets a number, and the tokens will name it along with a compass direction. A viewer asks whether each intersection has its own tokens, and the answer is yes. For the demo, an oak sapling stands in for a direction token and a jungle sapling for the caboose. The engine drops its token as it passes, a hopper sorter catches it and holds it like a memory, and the track flips. When the caboose token comes through, it clears the memory and the intersection goes back to rest.
Used tokens still have to go somewhere. Caboose tokens might get stored in a chest for Basket to collect now and then, or just dropped in lava, since they're easy to make. The direction tokens are named one by one, so Basket wants them back in the system: the outgoing track could dip down a block over a hopper under a slab and load them into passing carts, which would drop them off at the next station.
Out to the first one
Back on the server, Basket rides the double line past the big hole that will be Basket Station, which for now goes by "Basket Station Quarry," and on to the spot for the first intersection. It's already laid out at 5x5, a bit bigger than needed. It's a T, so it only has to read one token besides the caboose: go straight, or turn. The redstone will go eight to ten blocks down, as long as nobody's base turns out to be hidden underneath.
That worry has happened before. At the station, the underground workings share a wall with another player's basement full of furnaces. Basket shifted the plans two blocks over to make it fit, and has cleared the station's column all the way to bedrock so nothing else ends up in the way. The credits run to the end of the video with no gameplay after them.