Walkie-talkie technology first produced in the twenties, was born in Westinghouse's laboratory. An ecstatic inventor named John Kermode wanted to automate the postal receipts "whimsical" when it came to thinking that every idea of the application of electronics was so novel. His idea is to make an intercom tag on the envelope, and the message in the intercom is the addressee's address, just like today's zip code. To this end Kermode invented the earliest walkie-talkie logo, the design is very simple, that is, a "bar" said the number "1", two "bar" said the number "2", and so on. He then invented a walkie-talkie reading device consisting of basic components: a method of measuring reflection strips and blanks (ie, edge-located coils); and a method of using the results of the assay, ie translating Coder.