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Electronic counter - Other uses of electronics
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Other uses of electronics

Electronic counter

Electronic counter circuits record the number of pieces produced by a certain machine, or the number of vibrations that occur per second, or speed, or distance, and they also easily display the results of addition, subtraction and other arithmetic operations.

Mechanical counter

The mechanical counter in the car shows the number of miles it has traveled.

As for the electric counter, it shows the amount of electrical energy consumed. It is worth noting that tracking what happens inside such mechanical counters is very important.

The most commonly used mechanical rotary counters are (201). In them, shaft 1 rotates the cylinder connected to it and numbered from zero to 9. When this cylinder rotates from zero to the tenth unit in it, which corresponds to zero in the next cylinder, gear S rotates the latter around shaft B, thus moving the tens numbers from zero to one. This happens whenever the first cylinder completes a full revolution around axis 1. Also, when the second cylinder completes a full revolution, it pushes cylinder C, which shows the hundreds digit, one digit, and thus we can read on such a counter up to the number 999.

To turn column A, we can use an electric coil, a ratchet, and a gear. When the electric circuit is closed, the current flows in the ratchet that turns column 1 one digit.

These devices are used in fast electronic computers to record large numbers if necessary.

What exactly happens in this counter? Every time the capacity of the ones counter (202) is completed, one of the pulses is transferred to the tens counter and the first returns to zero and the pulse is transferred from it to the hundreds counter. Therefore, electronic circuits are formed that give a single output pulse whenever a certain number of input pulses from one of the sectors of the counter reach it.

201 - Mechanical counter
202 - Sequence of digital operations

It is also possible to calculate repetitive mechanical operations using this circuit closing method (203) which makes the work of the counter electrical. The electric current passes through the coil whenever the circuit is closed, thus driving the ones counter. The switch that closes the circuit is moved using some weights or one of the other means.

Electronic methods can perform the same functions as mechanical methods but with greater accuracy, ease and better reliability. The counter in Figure (204) is equipped with an infrared light beam that, when it falls on a photoelectric cell, causes an electric current that is amplified and transferred to the next stage. When the light is cut off, an electric pulse is formed that is transferred to the ones counter. When the units of the first row are complete, the pulse is transferred to the tens counter, and so on...

203 - Electro-mechanical counter.
204 - Electronic counter.

The ring counter gives one output pulse for a certain number of selected pulses entering it. For example, in the case of the decimal system, it gives one output pulse for ten pulses entering it (205). This counter may include rectifiers, thyratrons, or other devices that remain stable until a trigger pulse reaches them, then they remain in the new position until another pulse reaches them, returning them to their original position. The pulses reach the rectifiers via the diodes D. All diodes, except the first, are characterized by a large bias voltage that comes to them via the control rectifier attached to them. Therefore, the first pulse only triggers the first control rectifier, so the current is transferred in it, causing a low voltage in the second diode. As for the next pulse, it becomes capable of triggering the second control rectifier, etc., and thus ten consecutive pulses pass through the circuit. In addition, the last rectifier gives an output pulse to the tens panel, and at the same time gives another pulse that cancels the ones row completely. It is worth noting that six rows are enough to reach the number 999999.

205 - Ring counter.