10-04-2017, 07:25 PM
We all must have seen the famous game show "who wants to be a millionaire" and many like quiz where in the initial stages of some of the participants are asked to complete a short quiz, participants asked a len Committee, which meets his first by pressing the buzzer to take a "hot spot".
Other schemes HERE
Well all might not be so lucky to get in these games, but you can, of course, love to do and play with this little quick scheme finger first decisive right at your home.
The scheme is simple, using only a couple of circuits and some LEDs.
4 press to print the circuit breakers are located at 7475 chip that 4-Bit Dvustabil noe latch with complementary outputs.
Which button is pressed first, invokes the appropriate output IC 7475, which in turn leads to IC 7420 to instantly disable the other materials from other buttons, which makes the whole system of inactive, except the one which was the first trigger erezknopka.
The output of the latch on the corresponding led illuminates, indicating the number of the button that was pressed first.
This is a simple diagram of the game, which can be built in all electronic hobbyists, as well as schoolchildren.