Digital step-KM counter

Replies

• 

  Kaustubh Katdare

  Inserting the circuit diagram below -
  
  
  
  R1,R3____22K 1/4W Resistor
  R2________2M2 1/4W Resistor
  R4________1M 1/4W Resistor
  R5,R7,R8__4K7 1/4W Resistor
  R6_______47R 1/4W Resistor
  R9________1K 1/4W Resistor
  
  C1_______47nF 63V Polyester Capacitor
  C2______100nF 63V Polyester Capacitor
  C3_______10nF 63V Polyester Capacitor
  C4_______10µF 25V Electrolytic Capacitor
  
  D1_______Common-cathode 7-segment LED mini-display (Hundreds meters)
  D2_______Common-cathode 7-segment LED mini-display (Kilometers)
  
  IC1______4093 Quad 2 input Schmitt NAND Gate IC
  IC2______4024 7 stage ripple counter IC
  IC3,IC4__4026 Decade counter with decoded 7-segment display outputs IC
  
  Q1,Q2___BC327 45V 800mA PNP Transistors
  
  P1_______SPST Pushbutton (Reset)
  P2_______SPST Pushbutton (Display)
  
  SW1______SPST Mercury Switch, called also Tilt Switch
  SW2______SPST Slider Switch (Sound on-off)
  SW3______SPST Slider Switch (Power on-off)
  
  BZ_______Piezo sounder
  
  B1_______3V Battery (2 AA 1.5V Cells in series)
• 

  adinickluv

  Is it a some kind of digital distance meter?
  Can somebody explain its working??
• 

  reachrkata

  Hmm !!!
  It is a bit tedious to explain this circuit, because there is a reason for each and every value of R & C used.
  
  Best is to use a simulation to check only the IC1A,B,C part with the transistors. That may give a clue to why your buzzer is always buzzing !!!
  
  -Karthik