What is it? Answers CXI

Friday, April 07, 2006

630. Carbon ring microphone, used with permission of Cool Microphones, here is his description of it:
"It is a carbon granule microphone. The granules were electrified, and when sound vibrated the electrified carbon granules between two thin metal sheets, it reproduced the sound electrically. The technology goes back to the earliest of telephones and was used in radio from the 20s through the 30s. Phones used the technology through the fifties."





631. Night watchman's key, it was kept in a small box at a checkpoint in a large building or factory, the security guard would take the key, insert it into a recorder worn on his belt, and turn it to record the checking time.






632. Integrated circuit insertion tool











633. Not sure exactly what this is, I haven't been able to find another one like it.








634. Lightning rod tip, needs to be replaced when struck since the metal melts and loses its shape.



635. Wrest saw set


"Henry Boker, Germany"




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