THE LIGHT WILL ACTIVATE THE SIREN

LIGHT WILL ACTIVATE THE SIREN

The proposed German magazine “Funkamateur” light relay is activated when light falls on the photoresistor R1 (see diagram) — when this occurs, a loud siren sound. Transistors VT1, VT2 equivalent odnoimennogo of the transistor included under the circuit of the sawtooth generator. The oscillator frequency is determined by the capacitance of the capacitor C1, the internal resistance of the photoresistor R1 and the resistor R2. Transistors VT3, VT4 included in the Darlington circuit, perform the function of the AF amplifier. It is possible to replace. Photoresistor — any domestic; transistors: VT1 – КТ3107, KT361, КТ203; VT2, VT3 blocking – KT315, КТ312; VТ4 – КТ503, КТ603, КТ815 with any alphabetic indexes.
Concept.
Schematic diagram of the relay.

Recommend to read

  • ELECTRONIC IGNITION:OPTIONSELECTRONIC IGNITION:OPTIONS
    We are talking about different versions of electronic ignition devices (UEZ), is made as transistors and IC. The lack of scarce elements, as well as the simplicity of the schemes allow...
  • CLAMP “THREE WOOD”CLAMP “THREE WOOD”
    When gluing different items instead of the clamp you can use a clamp consisting of two strips, wire and click. The arrangement of such clamps can be seen from Fig.   S. FEDORENKO, g....