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In season two of Stargate there is an episode called "The Fifth Race" where Jack is implanted with Ancient knowledge that leads him to the Aguards. During this episode Captain Carter leads SG1 to a planet where they dial in to SGC to say a second, closer and hotter sun has risen and they will die if they stay there but they can not come back because the Dial Home Device (DHD) is shutting down half way through address and not establishing a wormhole. Because of Jack's ancient knowledge imprint he draws out schematics for the DHD and how to fix it. SGC dials SG1 and sends through the plans to fix it. They fix it and come home.
My question is; why the hell don't they come back when they established a wormhole to say "We can not establish a wormhole?" OR why not walk through the wormhole after SGC establish it to send them protective equipment or plans? I did not think that it was strictly I dial and only I can go through, if it is supposed to work like a telephone what's to say I can't dial you and you walk through to me??