Long-range transmitter
Production information
Manufacturer	Asgard
Designer	Asgard
Technical specifications
Power source	Unknown
Usage
Affiliation	Asgard Goa'uld Tau'ri Replicators

[Source]

Long-range transmitters are devices capable of transmitting communications over long distances. Such transmitters are located with a series of other communications-related equipment at the top-rear port section of Daedalus-class ships but are likely to also exist on ships from various races. (ATL: "The Intruder")