Event Horizon Question

[Lt. Brigadier General]

Lt-BG here!

How does the gate know when to shut off after everyone comes through? I've always wondered...

Thanks,
Lt-BG

[SaberBlade]

Both gates work together. When something goes through one gate it's stored and transmitted to the other, which then turns them back to normal. When the buffer of the receiving gate is clear or nothing is being received (signal, another person or object) it turns off.

[gateraid]

Both gates work together. When something goes through one gate it's stored and transmitted to the other, which then turns them back to normal. When the buffer of the receiving gate is clear or nothing is being received (signal, another person or object) it turns off.

That, and when the VFX people decide to turn of the effect Sometimes it makes little sense, like when it shuts off literally right behind the last traveller.

[JosephGracey]

I always thought it was Walter turning it off after he knew all the team were through but both reasons make sense in my head anyway.

[gateraid]

I always thought it was Walter turning it off after he knew all the team were through but both reasons make sense in my head anyway.

What SaberBlade said is the correct answer, although one could be forgiven for reaching a different conclusion if you based it solely on what was observed from the gate.

[Quizziard]

It could be argued there's a motion detector in the gates, as they seem to be able to stay open for ages waiting for someone to give a big heroic speech just in front of the gate, but close the minute they're into the event horizon.

"Whenever is best for the plot".

[thekillman]

i believe it's said on various occasions that Walter can shut it down.


ironically, every time they said so, the answer was "i can't". with the black hole, for example

[Quizziard]

i believe it's said on various occasions that Walter can shut it down.

There's a big difference between a "normal" Stargate (i.e. controlled by a DHD) and the SGC Stargate, controlled by the MacGyvered "dialling computer". They can shut down there's because they have access to the internals. The OP's question appears more generic...

[LtColMoreau]

Exactly, it's whatever was handy for the story. Obviously sometimes it stays open forever while someone says goodbye to someone else, other times it closes right away.

It's kinda like how Star Trek doors know not to open when someone wants to lean on them.

[fems]

After hearing Hammond complain about the budget more than once I do believe Walter (or whoever is at the dialing gate) shuts it down the moment all the relevant people at the SGC have gone through the gate, which we obviously see in the off-world scene when everyone has stepped through.

It's possible that when they dial Earth from off-world that the GDO keeps transmitting its signal until it actually goes through the gate to Earth or if the person wearing it turns it off (because of an ambush or something) and then the connection is terminated when no people/frequencies are being sent through.

Considering the few times we've seen a gate under water (either fully submerged or only partly) and how it functions then it's safe to assume there is some sort of sensor, most likely to record differences in pressure or motion...