Pings can be detected by protocol loggers like ippl. The SkyCube radio emitted periodic beaconing pings which contained 120-byte messages from the Kickstarter backers. A special process, called the reincarnation server, periodically pings each device driver. A transducer is a device that can transmit and receive acoustic signals ("pings"). A few minutes later, her sonar picked up the pings of ships dead astern. The pianos provide occasional pings and trills of other birds in the background. Furthermore, when "U-571" is being depth-charged, the German destroyer is using active sonar pings. They continued to search the sea floor within of where faint pings were heard. If he pings that fence he is right there. Faint "pings" from the ULB attached to the aircraft's CVR were also heard. Indonesian officials confirmed that faint pings had been heard in the search area. The pings had stopped abruptly early on the morning of April 26. Within the first day, there were about average 4 Pings a second. Officials confirmed that "pings" from the aircraft's ULBs were also heard near the area. After several "pings", a slide guitar played by David Gilmour gradually joins.