From The Stargate Omnipedia
Device developed at Stargate Command
by Samantha Carter
and a team of scientists, designed to interrupt the transmission of Goa'uld
communications and the function of remote control devices, including Asgard transporters
. The team worked on making the device portable enough to fit in the back of a surveillance vehicle.
The device was successful in performing its function when first tested against the Goa'uld Osiris, who was using Asgard transporter technology to covertly enter and exit the residence of Daniel Jackson in order to probe his mind while he slept. The Goa'uld's escape thwarted, Osiris was captured and removed from its host body, Sarah Gardner. The first portable version of the frequency jammer, however, is presumed destroyed by Osiris' za'tarc weapon.
Chimera - Carter announces the frequency jammer is nearly completed, just in time to capture Osiris before she makes her escape following an unconscious interrogation of Dr. Jackson in his residence.