Speed test circuit reaction of is simple planning. This circuit functions for game to test speed reaction of a man. Mode of the action of this peripheral is hardly easy to be comprehended. This thing is caused by this peripheral only lapped over by some Logical Integrated Circuit, counter, timer IC and decoder. Becoming timer IC to explain is IC 555. At the decoder we can apply IC 7445 and counter applies IC 7490. Logic IC applied at U1A until U4A is 7400.Following is mode of action from reaction speed testing tool. After the starting button is pushed, hence during a real quickly IC 555 giving some row of pulse towards IC chopper 7490. Effect [of] the thing is LED 1to 10 will turning on sequentially. Here in after, if the stopping button is pushed, a life last LED will be turning on continually. When oscillator awakening pulse of bell flamed to be finite a pulse will be yielded, for example every 20 md, hence countable player reaction time by seeing LED which is stay on.
New game can be made a fresh start, after RESET is pushed. By using component value which there is in diagram schematic, circuit will only consume source of the voltage is 5V and the current is 120mA stabilized. Oscillator frequency can set up by P1 between 10 to 80 Hz. When we wish LED attachment, can be attached a LED which is break even with resistor 200 ohms between outputs of N3 with positive voltage. This LED will live as indicator that peripheral in stand-by condition after player buttons START.
Good Luck!!
