The oldest operating satellite (older than the Voyagers) appeared to fail to due a battery issue, but somehow woke up in a mostly-working state soon after. It was noticed by activitsts in Poland, and was used to bounce radio messages out of the country. Since satellite communication is pretty directional, and into the sky, it was difficult-to-impossible to triangulate the source of the signals.
The oldest operating satellite (older than the Voyagers) appeared to fail to due a battery issue, but somehow woke up in a mostly-working state soon after. It was noticed by activitsts in Poland, and was used to bounce radio messages out of the country. Since satellite communication is pretty directional, and into the sky, it was difficult-to-impossible to triangulate the source of the signals.