Ham Radio's role -- the search and rescue team was unable to contact their command post, but used ham radio to relay emergency traffic:
"Because of the dense forest and canopy in the remote location, the rescue team was unable to communicate with the command post that the pair had safely been found.
“They utilized an amateur radio frequency, commonly known as HAM radio, to establish communication,” officials said. “After broadcasting ’emergency traffic’ on the HAM radio, their call was immediately answered by a retired El Dorado County Communications Supervisor who was a HAM operator monitoring frequencies from his home. This HAM operator then contacted the El Dorado 911 center, which provided the information to Calaveras Dispatch, and the SAR command post was notified.” "