1) Device 2) Pick 3) Plectrum 4) Radio electronic 1) Plectrum 
A Plectron is a specialized VHF/UHF single-channel, emergency alerting radio receiver, used to activate emergency response personnel, and disaster warning systems. Manufactured from the late 1950s, through the late 1990s, by the now defunct Plectron Corporation in Overton, Nebraska, hundreds of thousands of these radios were placed in homes of fir...
plectron 1. The hammer form assumed by certain bacilli during sporulation. 2. A small thin device (of metal, plastic, or ivory) used to pluck a stringed instrument.