Electronic Cricket Match Game

This electronic cricket is a present for Kids. This simple battery powered circuit can be used to play Cricket Match with your friends. Each LED in the circuit indicates various status of the cricket match like Sixer, Run out, Catch etc. The Circuit uses two ICs ,one in the Astable mode and the second in the display driver mode. IC1 is wired as an Astable Multivibrator with the timing elements R1, R2 and C1. With the shown values of these components very fast output pulses are generated from the Astable.

Output from IC1 passes into the input of IC2 which is the popular Johnson Decade counter CD4017. It has 10 outputs. Of these 8 outputs are used. Output 9 ( pin9) is tied to the reset pin 15 to repeat the cycle. When the input pin 14 of IC2 gets low to high pluses, its output turns high one by one. Resistor R3 keeps the input of IC2 low in stand by state to avoid false indications.

Electronic Cricket Circuit Diagram

When the Push Switch S1 is pressed momentarily, the Astable operates and all the LEDs run very fast sequentially. When S1 is released, any one of the LED stands lit which indicates the status of the match. For example, if LED D7 remains lit, it indicates Sixer and if LED 8 remains lit, it indicates Catch out. Label each LED for its status as shown in the diagram. Pressing of S1 simulates Bowling and Running LEDs indicates running of Batsman.

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Automatic Curtain Opener Circuit Diagram

This circuit can be used with a timer clock to open and close curtains or (vertical) Venetian blinds. The curtain or blind is driven by  an electric motor with a reduction gearbox fitted to the control mechanism of the curtain or blind. This circuit is ideal for giving your home an occupied appearance while you are away on holiday or for some other reason. In the author’s house, this arrangement has provided several years of trouble-free service on a number of windows fitted  with Venetian blinds. 

The original design was a simple relay circuit with pushbuttons for opening and closing and reed switches acting as limit switches. The mechanical drive is provided by a small DC motor with a reduction gearbox and pulley (all from Conrad Electronics).  It was later modified to work automatically with a timer clock. The timer operates a small  230-VAC (or 120-VAC) relay with a changeover contact. Thanks to the two timers, the motor stops after a few seconds if one of the reed switches is missed due to a mechanical defect. 

Automatic Curtain Opener Circuit diagram :

Automatic Curtain Opener Circuit Diagram

 

The circuit works as follows (see Figure 1). In the quiescent state, relays RE1–RE3 are de-energised and the motor is stopped. Open the blind: 

When the timer clock applies power to the 230-V (120-V) relay RE3, the voltage at the junction of C1 and R1 goes high. IC1 (a 555)  then receives a trigger pulse on pin 2, which causes its output (pin 3) to go High and energise RE1, which in turn causes the motor to start running. When the magnet reaches reed  switch S1 (‘Open’), the 555 is reset. If the reed  switch does not operate for some reason, the relay is de-energised anyhow when the  monostable times out (time delay = 1.1 RC;  approximately 5 seconds). Close the blind:

The timer clock removes power from RE3, which causes a trigger pulse to be applied to the other 555 timer (IC2) via R5 and C4. Now the motor starts running in the other direction. The rest of the operation is the same as described above for opening the blind. Diodes D2 and D5 prevent the outputs of the 555 ICs from being pulled negative when the relay is de-energised, which could otherwise cause the timer ICs to malfunction. 

All  components  of  the  mechanical  drive  come from Conrad Electronics [2]: a motor with a reduction gearbox (type RB32, order number 221936) and a pulley (V-belt pulley, order number 238341) on the output shaft. An O-ring is fitted to the pulley to provide  sufficient friction with the drive chain of the Venetian blind. The magnet for actuating the  reed switches is a rod magnet with a hole in the middle (order number 503659), and the chain of the Venetian blind is fed through this hole.

Author : Ton Smits  - Copyright : Elekto

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Wire Loop Game Circuit Diagram

In the ‘Wire Loop Game’, a test of dexterity,  the player has to pass a metal hoop along a  twisted piece of wire without letting the hoop  touch the wire. Usually all the associated electronics does is ring a bell to indicate when the  player has lost. The version described here has  a few extra features to make things a bit more  exciting, adding a time limit to the game and a ticking sound during play. 

Two 555 timer ICs are used to provide these  functions. IC1 is configured as a monostable which controls the time allowed for the  game, adjustable using potentiometer P1. IC2  is a multivibrator to provide the ticking and Two 555 timer ICs are used to provide these  functions. IC1 is configured as a monostable which controls the time allowed for the  game, adjustable using potentiometer P1. IC2  is a multivibrator to provide the ticking and he continuous buzz that indicates when the  player has touched the wire with the hoop. 

Wire Loop Game Circuit diagram :

Wire Loop Game Circuit Diagram

When the monostable is in its steady state,  the output of IC1 (pin 3) is low. T1 acts as  an inverter, and D2 is thus forward biased.  R8 and R4 are therefore effectively in parallel, with the result that IC2 produces a low audible tone. The value of R4 is considerably  greater than that of R8, and so the frequency  of the buzz generated by IC2 is chiefly deter-mined by the value of R8.

When the monostable is triggered, the high  level at the output of IC1 is again inverted  by T1. D2 is reverse biased and so R8 is effectively removed from the circuit. The frequency of IC2 is now largely determined by  the value of R4. The ratio of R4 to R5 and the  value of C4 affect the mark and space periods for the multivibrator: for a satisfactory  ticking sound short pulses with long gaps  between work well. 

Whether a sound is produced also depends  on the voltage on pin 4 of IC2. When the 9 V  supply is connected the monostable is initially inactive and there is no voltage across  C1. Pin 4 (reset) on IC2 is thus low and no tone  is produced. IC1 is activated by a brief press of  S1, which generates a low-going trigger signal  on pin 2 to start the game. C1 now charges via  D1 and IC2 is allowed to oscillate, generating  the ticking sound. 

The pulse width of the monostable sets the  game duration, and can be adjusted using  P1. If the allowed time expires, or if the reset  input to IC1 is taken low (which happens when the hoop touches the wire), the monostable  returns to the quiescent state. This causes IC2  to generate the low buzz sound. D1 is now  reverse biased and C1 discharges through the  relatively high-valued resistor R9. After a few  seconds the voltage across C1 falls sufficiently  that the buzz stops and the circuit is ready for  the next player. 

The circuit can be built first on a breadboard,  so that the component values can easily be changed to suit particular preferences for  game duration and buzz pitch. When suitable  values have been selected the circuit can be  built more permanently on a printed circuit  board. The author used a sheet of plywood  to form a base for the game, the twisted wire  being fixed to the board and wired to the electronics mounted below it. 

Author: Andreas Binner

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