The thermal fire alarm device of Abushkevych relates to the fire alarm system and can be sued to detect rise in temperature of environment above he established limit value. The annunciator comprises a LED indicator, two transistors, two diodes, two condensers, five resistors and two input terminals. In addition there is a current limiter, the third transistor and the third condenser in it and the thermal sensor is made as a thermoresistor. In the annunciator at the expense of interrelations of the specified elements and application of the thermoresistor in the form of the thermal sensor the there is an increase of temperature stability of the annunciator functioning in a wide of power supply voltage range and even in conditions of elevated vibration expanding area of its application.
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