SU442565A1 - Controlled Multivibrator - Google Patents

Description

one

 The invention relates to a pulse technique, can be used, for example. shsh poobpazovani levels of external illumination, in the parameter of the pulse signal.

Known controlled multivibrator auth. St. No. 258379, which produces pulse signals whose parameters (duration, pause, frequency) are electrically controlled. . The purpose of the invention is to control the duration, pause and frequency of the pulses by changing the level of ambient illumination by the fact that the proposed multivibrator additionally contains two perceived illumination of the photoresistor, which are connected to a common point to the positive power supply bus, and each free end to the corresponding common point of the oasis transistor and | two resistors to the collector circuit of the transistor vivovibrator. The drawing shows a diagram of the device.

The% vibrator contains transistors I and 2 of the same conductivity T1 (p-1r-p), time setting capacitors 3 and 4, disconnecting diodes 5 and 6, additional transistors, 7 and 8 of another type of conductivity I (J, additional diodes 9 and 10, resistive dividers II. 12 and 13, 14, power supply 15, photoresistors 16 and 17, resistors 18 D9 IS. 20, 21 in the collector circuits of trans-i resistors I and 2 of the multivibrator and resistors 22,23 in the collector circuits transistors 7 and 8.

The bases and collector circuits of transistors I and 2 are connected respectively to the collector circuits and bases of transistors 7 and 8, the anodes of diodes 9 and 10 are connected respectively to the middle terminals of resistive divisors II, 12 and 13,14, the cathodes of the diodes (10 are connected respectively with.

The collectors of transistors 7 and 8, which euittery are connected to the power supply busbar 15, are connected to the same terminals of resistive dividers 11,12 and 13, 14, the other terminals of which are connected through the capacitors 4 and 3 to the bases of transistors I and 2, The photoresistors 16 and 17 are connected by a common point to the positive power supply line, about which the emitters of transistors I and 2 are connected. The free end of photoresistor 16 is connected to the common base point of transistor 7 and resistors 18.19 in the collector circuit of transistor I. Free end of photoresis ora 17 attached to the common point of the base of the transistor 8 and the resistors 20, 21 in the collector circuit of the transistor 2,

The device works in the following way.

When discharging the time of the capacitor, for example, 3, through the transistors I and 8, the discharge current is determined by the voltage divider formed by the resistor 20 and the photoresistor 17, the voltage

is determined

From the specified divider, in a similar way, the discharge time of the driving capacitor 4 occurs. The discharge current of the capacitor through transistors 2 and 7 is determined by the illumination perceived by the photoresistor 16,

As a result, the duration, pause, and pulse frequency change with changing ambient light levels.

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Managed multivibrator according to St. No. 258379, different

auth

topics that, in order to control the duration, pause and frequency of the pulses by changing the level of ambient light, it up to: contains two light-sensitive photoresistors that are connected to a positive point of the source bus: the power supply and each free end to the corresponding common base flow an additional transistor and two resistors in the collector circuit of the multivibrator transistor.