The telegraph sounder was used at the receiving end of the line to make the Morse code message audible.
2.
The observatory had a bronze anemometer, heated to resist icing, which was linked by wire to a telegraph sounder in the observatory.
3.
:: : In looking over many web pages on these and similar things, It seems as though it might have an additional purpose as a telegraph sounder.
4.
In some applications, a pair of headphones replaced the telegraph sounder, being much more sensitive to weak signals, or a Morse recorder which recorded the dots and dashes of the signal on paper tape.
5.
When the coherer conducts better, battery " B1 " supplies enough current through the coherer to activate relay " R ", which connects battery " B2 " to the telegraph sounder " S ", giving an audible click.
6.
The basis for the operation of the coherer is that metal particles DC circuit powered by a battery that created a " click " sound in earphones or a telegraph sounder, or a mark on a paper tape, to record the signal.
7.
Based on the suggestions made by these lawyers, Childs conceived of a system where there would be a central office and a signaling system where any lawyer could signal to that office to connect his wire to a specified office, using a device similar to Charles Wheatstone's " Morse telegraph sounder.
8.
These included such sensors as the thermocouple ( from the work of Thomas Johann Seebeck ), the resistance thermometer ( by William Siemens based on the work of Humphry Davy ), and the electrical strain gauge ( based on Lord Kelvin's discovery that conductors under mechanical strain change their resistance ) and output devices such as Samuel Morse's telegraph sounder and the relay.
मोबाइल