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... = (Vs-Vf)/I ………………………………………..(6) = (Vs-Vf)/20mA =445 Ω Typical value =560 Ω The purpose of the series resistor is to limit the current to the LED [pic] Fig 2.22.6.3 Connection of decoder to seven segment display. 2.22.7 ALARM The alarm consists of a buzzer driven by a thyristor.It a resistor transistor logic(RTL).The frequency of sound is approximately 3KHz.When the count reaches the max.(binary- 110010). [pic] Fig 2.22.7 Alarm circuit The high states of count 50 are applied to the inputs.Q7 turns on; its collector voltage becomes low (0.8v).Q8 turns thus turning on the thyristor by gate triggering which in turn on the buzzer.
PASSENGERS COUNTING SYSTEM
The Passengers Counting system is a digital counting device. It is used to keep the count of passengers present at the bus at any particular time and the cumulative number carried within a give range of time.
Details
| language |  | english |
| wordcount |  | 7187 (cca 20 pages) |
| contextual quality |  | N/A |
| language level |  | N/A |
| price |  | free |
| sources |  | 4 |
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Preview of the essay: PASSENGERS COUNTING SYSTEM
1.0 CHAPTER ONE BACKGROUND The Passengers Counting system is a digital counting device. It is used to keep the count of passengers present at the bus at any particular time and the cumulative number carried within a give range of time. Counting of persons, objects, or animals has been act of human life for as long as man’s existence. The project is done considering the many methods of counting and formulae used by the statisticians. The usual manual counting is impossible in some situations especially when accuracy, speed, reliability and efficiency is of high concern. It is due to these setbacks that of manual counting that digital modern devices are used in order to keep phase with dynamic technology, The reasons for choosing to undertake this project are; I. It is in my scope of study. II. Ease of system design, construction and application towards solving the counting problem. 1.0 BLOCK DIAGRAM [pic] Fig 1.0 B1ock diagram of the system 1) LIGHT SOURCE -produces a beam of light towards the detector. (2) DETECTOR -detects the presence of light from the source of light. When the beam of light is interrupted, it sends a pulse ...... = (Vs-Vf)/I ………………………………………..(6) = (Vs-Vf)/20mA =445 Ω Typical value =560 Ω The purpose of the series resistor is to limit the current to the LED [pic] Fig 2.22.6.3 Connection of decoder to seven segment display. 2.22.7 ALARM The alarm consists of a buzzer driven by a thyristor.It a resistor transistor logic(RTL).The frequency of sound is approximately 3KHz.When the count reaches the max.(binary- 110010). [pic] Fig 2.22.7 Alarm circuit The high states of count 50 are applied to the inputs.Q7 turns on; its collector voltage becomes low (0.8v).Q8 turns thus turning on the thyristor by gate triggering which in turn on the buzzer.
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Princess R.Fairly written on a subject matter which only a few understand because of its too technical nature.