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The bistable circuit or the bounce circuit
- Electronic counting .. Electronics

The bistable circuit or the bounce circuit

We see in Figure (214) a drawing of a circuit characterized by having two stable states, one of which remains until it is excited and then switches to the other state. In this circuit, the base of transistor A is negative, while the collector current in it is large, making it, i.e. the collector M1, a positive terminal, so the base of transistor B, i.e. terminal Q2, also becomes positive. In this case, the collector current M2 is small and a small voltage is generated across the resistor M2, keeping the base of transistor Q1 in its negative state. These conditions combined do not change except through a new input pulse, after which the collector M1 becomes unable to conduct a large current, and as a result the voltage drop across the resistor M1 decreases, turning the base Q2 of transistor B into a negative state. In this case, transistor B becomes conductive, and the increasing voltage drop across the resistor M2 makes its collector M? Positive, and therefore the base Q1 circuit remains in this state also until a second pulse comes to return it to the first state. And so on without interruption. It is worth noting that the output of this circuit can be taken from the collector M2.

It is known that any device that can remain in one of the two states "connected" or "cut off" can be used in counting operations. Binary counters usually divide the number by two (215), while decimal counters divide by ten and to calculate the number of oscillations an electronic gate (key) is used that opens and closes the circuit for a limited period that allows the counting process to be carried out.

As for Geiger counters, they help measure the intensity of radiation. They include a central anode with a positive and high voltage placed inside a casing containing a specific gas mixture (216) whose extremely fast particles ionize the gases, thus releasing a number of electrons that head towards the anode and lead to the release of a number of small pulses.

Standard-Digital Conversion

Standard information represents a fact calculated in an analog or analogical way by means of a voltage or speed indicator that shows voltage or miles per hour, for example. Among the means used in standard-to-digital conversion are those shown in Figure (217), where a photoelectric eye records the result of the division whenever it passes in front of it.

There is another means that includes sensitive devices corresponding to the white sectors representing the number zero, the black ones representing the number 1 - and it is known that rotating the disk by one step is sufficient to perform the binary count 1 0001, 0010, 0011, 0100, etc. 00.

214 - The bounce circuit or the bistable circuit
215 - Counters in series.
216 - Geiger counter.
217 - Methods of converting standard quantities to digital quantities.