THE TIMER CONTROLS THE SOUND

THE TIMER CONTROLS THE SOUNDThe device, whose scheme is published in the journal “Popular electronics” (USA), produces a positive pulse when a sound (for example, firing of the gun) reaches the microphone B1 (see diagram). The variable resistor RZ adjust the sensitivity of the instrument, and the led V4 indicates it is turned on. Break contact S1, the finish associated with a ribbon, breaks the supply circuit of SCR V5 as soon as the athlete crosses the finish line.

In the device, you can use any silicon transistors of n-p-n and p-n-p conductivity, for example of the KT315 series and КТ301, SCR КУ101 or КУ502 with any alphabetic index, led АЛ307А, B. as a microphone recommend the use of “speaker” DEM-4m.
 
THE TIMER CONTROLS THE SOUND

Noticed mistape? Highlight it and press Ctrl+Enter, to inform us.

Recommend to read

  • COMBINATION LOCKCOMBINATION LOCK
    About code locks wrote more than once. However, most of them are difficult to repeat. Design suggested by our Bulgarian friends (the journal "Radio Television Electronics"), devoid of...
  • PROTOTYPE -HOURGLASSPROTOTYPE -HOURGLASS
    The Romanian magazine "Technium" offers a diagram of the electronic timer operates on the principle of the 5-minute hourglass clock every minute. The indication to carry out the LEDs....

Spelling error report

The following text will be sent to our editors: