ABSTRACT
What is a relay? There is probably no engineer or technician who would admit to his colleagues that he
does not know what a relay is. It is an element so widely used in engineering that every engineer has had an opportunity to deal with it to some extent. Just for the sake of experiment try to define the notion ‘‘relay’’ . . . I don’t think you will be able to do so at the first attempt, nor the second, and if you try to look up the word in a dictionary you will be puzzled even more. See for yourself: Relay
1. A fresh team of horses, posted at intervals along a route to relieve others
2. A series of persons relieving one another or taking turns; shift
3. To work in shifts
4. A sport race
5. A system of shifts at an enterprise
6. To provide with or replace by fresh relays
7. To retransmit
8. A switch.
