Thyristor dimming lamp circuit with light stabilization function (3)

It is a thyristor dimming lamp with novel connection method and light stabilizing function. R.R. Connect with RI, RP
to form two voltage dividers, and their voltage dividing points
are connected to the emitter and base of triode VT1 respectively
. When the ambient light is dark,
the resistance of the photoresistor RL becomes larger,
the base potential of VT1 becomes
more negative relative to the emitter, and the collector current of VT1 increases,
so the charging rate of the capacitor C is accelerated, and the conduction angle of
the thyristor VT2 becomes larger,
the brightness of bulb E becomes larger. If the ambient
light is brighter and the Rl. resistance becomes smaller, the situation is opposite to the above. The VT collector current decreases, the C charging rate slows down
, the VT2 conduction angle decreases, and the light brightness also decreases. If the ambient light is very strong, the base potential of V1 and V1
will increase, which can cause VT1 to enter the cut-off state . Unable to charge, light E turns off automatically. Adjust the potentiometer RP
to change RI. Lj RP is the dividing point potential, so it also determines the brightness of the lamp E.
  When in use, adjust RP so that the desk lamp E emits the appropriate brightness for the desk. The illumination on the working surface will automatically be
stable in the future. Other precautions are the same as in the previous two examples.