literally play letters and their machine would automatically output upholstery me representing the letters when like this four-letter p more like this or letter r or like this four-letter be so we have an output signal containing various combinations of these be impostors a signal that accurately represents the message pipe donatella typewriter behind the counter the mechanical nervous system change words two holes on tape and the holes on tape to electrical impulses speeding over the wires notice at the lowest level this system is exchanging you to the president's score absence of electrical current in a sequence divided using o'clock so how fast can our internal clocks round who the limiting speed was not the cause of the then and today the speed of transmission was physically limited by the minimum spaces between these impulses or the poultry in this problem plagued engineers who were testing underground submarine cables using the existing morse code system it's similar to and ako laura a sustained no all if one sense toss 2000 over a long undersea circuit they will run together at the receiving end because a simple we receive at the far end of the circuit will be a slightly longer smooth dough rise and fall not an exact replica then sending pulse is too fast resulting intersymbol interference this occurs for example when the