Time base using a delay circuit touch lamp

  
Using a wire connection, use NFA.55 timebase circuit delay type light touch switch, it can directly replace ordinary mechanical switch, without having to change the original interior wiring.
Time base using a delay circuit touch lamp - schematic

The circuit is powered back with good hoof Chapter 96 cases, especially on} U F is lit or put out the lights off, the circuit can always output a voltage fiV steady stream education for state-based circuit NF, 155 electricity. Usually, NE5ji in a stable state, feet lose thirty low grain lrril tube VT1 shake the f J is R, the wear of the clamp level, VTI curse off, the lamp E does not shine. When the hand touch the electrode sheet M, the body leakage current through R, Wang injection diode VT2 base enables rapid VT2 conduction, which is equivalent to the trigger terminal feet NE555's input a negative pulse, time base circuit busied, foot jump into supplier level. Therefore, the thyristor VT1 gate potential elevation, VT1 get the trigger voltage and Ji Tong, E powered lamp light. At the same time, G stored charge through VTZ fast relief. After leaving the people at M, VT2 off recovery, 6V DC power on by R; the G Free electricity, so f, both ends of the potential rising. When rose 2 / 3VDO That 1V, when the base circuit is reset, pin restore low, wri lost trigger voltage when the AC zero crossing that is turned off, the lamp E goes out. In addition to the delay time of the circuit R. , C, has a charging time constant curse, but also by the length of time there is a touch off. When a finger touch time than K, G can store sufficient electrical discharge leaning, the "C. charge to 4V asked on the long, corresponding lamp lighting time will be longer. In addition, the load capacity of the circuit but also by steady pressure pipe vs dissipated power constraints, so the bulb E power not more than 40W.




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