U.S. power grid
The mini Stargate is a much smaller, more primitive version of a Stargate constructed entirely from Earth materials; specifically, 100 pounds of pure titanium, 200 feet of fiber optic cable, seven 100,000 watt industrial-strength capacitors, and a toaster. It is about six feet in diameter, large enough to fit one or two people diving through. It is capable of connection to an ordinary Stargate successfully, though the primitive materials prevent it from being dialled more than once before burning out. It also lacks the complex programming of a regular Stargate, having been designed to specifically dial Velona.
While there, he made numerous requisitions through eBay for various electronic items which he assembled in Carter's basement, creating a small Stargate which he used to gate to Velona to prevent Stargate Command from activating the weapon on the planet surface. (SG1: "Ascension")