Replicator Circuit of Cricket Chirping Sound
|
|
Overview
The purpose of the circuit is to imitate the chirping of the cricket for use as gadgets for amusement and props while being powered by 5V to 12V batteries. Terminology - Cricket – an insect that is part of the family Gryllide which is somewhat related to grasshoppers, mostly having long antennae, flattened body, muscular hind legs for jumping, and two pairs of developed wings; they have a good hearing and vision since their compound eyes enable them to see in several directions simultaneously
- 4093 – a quad 2-input NAND with Schmitt trigger inputs integrated circuit, generally characterized by small fluctuation in voltage supply, very high impedance, outputs that can sink and source, one output can drive up to 50 inputs, high speed gate propagation time, high frequency, and low power consumption
- 4060 – a 14-bit ripple counter with internal oscillator that has glitches which may occur in any logic gate systems connected to its outputs due to the slight delay before the later counter outputs respond to a clock pulse
Circuit Explanation The chirping of the cricket is created and can be heard when the left forewing is raised to a 45 degree and rubbed against the upper hind edge of the right forewing. The term stridulation is used to describe the created sound. There are two types of cricket songs that may be classified, a courting song and a calling song. The calling song is very loud for the purpose of repelling other males while attracting females. The courting song is used when the female cricket is close and has very quiet sound. According to studies, the crickets are chirping at different rates depending on the temperature of the environment and the species they belong to. The inclusion of IC2 and other related components are responsible for driving the loudspeaker via Q1 as they generate a suitable audio wave form of the chirping cricket. The two timers built around IC1C and IC1D are making a pseudo-casual way of interruption in the chirp, which makes it more realistic in the behavior of the sound. The outputs are being mixed into IC1B which is time delayed further by IC1A. This will then drive the reset pin of IC2. For more real life feature, the circuit may start to function in the dark and stop during the presence of light by using an optional photoresistor which can be attached across the reset pin and the positive supply. It will imitate more of the behavior of the cricket as closely as possible. The control of the volume can be adjusted by the value of resistor R9 or otherwise be a small potentiometer or a preset trimmer. The operation of the circuit is being powered by a battery source in the range of 5 V to 12 V. A small loudspeaker can be used to achieve optimum results. The loudspeaker may be pressed against a flat surface like a wooden table so that the chirping could be improved further and be concentrated. Application The cricket chirping circuits have been used in several toys as a form of entertainment for kids. One better use of the chirping sound is being utilized in smoke detectors to prevent a shrieking sound in the middle of the night especially if the smoke detector is running out of batteries. It is also a way of informing the household of a detection of fire or a presence of carbon monoxide build up for some advanced models. Source:redcircuits.com/Page111.htm
|
