
THE THERMOSTAT OF THE IRON

The scheme is simple electronic guard device published the magazine “Funkamateur” (GDR). Across the doors of the protected object stretched thin wire. Until he is whole, the tension on the bases of the transistors VT1—VT3 are few and they are closed. In case of wire break on VT1 through a resistor R2 receives the bias voltage, and this semiconductor device is opened. Now, through a chain of R2—R4, the transistor VT3 will get more offset. Relay K1 will work, and its contact system will include a siren, a buzzer or a lamp. Moreover, the elimination of wire break will not change the situation is to disable the watchdog is possible only with the switch ЅА1.
Not long ago, musical instruments even pop bands — be it saxophone, violin, accordion, piano, double bass and even a drum — gave his listeners a natural, “natural” sound. Today music has become different — is now in Vogue “electronic” sound.
Many readers of the magazine are building all kinds of model planes, ships, trains, cars and other equipment. However, for greater affinity with their prototypes it is desirable to “voice”, which will give them even greater appeal. Recall, for example, sounded like a train. First heard a gradually increasing noise of a train, then near the station he blows his whistle to his approximation, and stood, and noisily blowing off steam, making a sound like “poof poof poof”. Before leaving the station bell sounds, and the locomotive gives a farewell whistle before the journey.