Editing Stargate (device) (section)

===Dial-Home Device===
[[Image:Dial-Home Device.jpg|thumb|The Dial-Home Device]]

There are a handful of methods used in the shows to dial a Stargate, and the most common is with the use of a Dial-Home Device. Almost always referred to as the "DHD" for short, it is depicted as a pedestal-shaped device with a round inclined control panel on top, consisting of two concentric circles of "keys" and a translucent red (Milky Way) or blue (Pegasus) hemisphere in the center; the keys represent the symbols on the rim of the Stargate. By pressing these keys a traveler builds an address. The central hemisphere serves as an "[[Carriage return|Enter]]" key to activate the Stargate once a destination has been dialed. Each DHD only has 38 keys, 19 on each ring. According to [[Radek Zelenka|Dr. Zelenka]], dialing an address leaves a small imprint on the control crystals of the DHD, and about fifty addresses can be recovered from a DHD using the proper equipment. However, this gives no indication of the order in which the addresses were dialed, and no guarantee can be made as to the accuracy of the recovered addresses.<ref name="The Lost Boys">{{cite episode|title=The Lost Boys|episode-link=The Lost Boys (Stargate Atlantis)|series=Stargate Atlantis|series-link=Stargate Atlantis}}</ref>

[[Image:Dhdjumper.jpg|thumb|Pegasus/Atlantis puddle jumper DHD console]]
The [[Atlantis (Stargate)|Atlantis]] DHD is more similar to the Earth's dialing computer than an actual DHD, and looks more like a set of crystal panels. It can block out certain gate addresses.<ref name="Before I Sleep">{{cite episode|title = Before I Sleep| episode-link = Before I Sleep (Stargate Atlantis)| series = Stargate Atlantis| series-link = Stargate Atlantis}}</ref> The Atlantis DHD also has an extra control-crystal allowing the dialing of an eighth chevron during the dialing sequence and is the only DHD in the Pegasus Galaxy capable of dialing Earth.<ref name="Home">{{cite episode |title=Home |episode-link=Home (Stargate Atlantis) |series=Stargate Atlantis |series-link=Stargate Atlantis}}</ref> A similar DHD is also used on Puddle Jumpers, where the set of used glyphs corresponds to the galaxy of the Puddle Jumper. The [[Wraith (Stargate)|Wraith]] also travel through Stargates in small spacecraft called darts and have some means of remote-dialing them in a manner similar to Ancient ships.<ref name="The Lost Boys"/>

The show makes it clear that every Stargate originally had its own DHD, located directly in front of the gate and facing it.{{r|TANTALUS}} Over time, however, some DHDs have been damaged or lost. This has been the source of plot difficulties for the protagonists on several occasions, as it is still possible to travel to a Stargate that lacks a DHD, meaning that dialing home again will be much more difficult, if not impossible. One of the primary functions of the Mobile Analytic Laboratory Probe (M.A.L.P.), an [[unmanned ground vehicle]] that precedes an [[SG team]], is to confirm the presence of a DHD.{{r|TANTALUS}} In the absence of a DHD, a user must select the address by manually rotating the inner ring of the Stargate, and use an external power source, as the ring will not rotate unless it is energised.{{r|TANTALUS}} Pegasus Galaxy Stargates do not have a movable ring, so manually dialing these is impossible. Travelers can also emulate a DHD through a dialing computer as present at [[Stargate Command]]. Remote dialers have been used by several races like the [[Goa'uld]] and [[Asgard (Stargate)|Asgard]] in various episodes. As the Stargates in Stargate Universe are a different (less advanced model) the crew of the Destiny are forced to use such a device as no planet visited so far has any variation of DHD present.