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# A dimmer does the job but is not periodical without the human hand turning up and down the knob constantly.

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The light form a bulb can blink to a frequency. Suppose one chooses 0.1 Hz, the bulb will be pulsing at that frequency. If the voltage is 5 volts, the result is a straight away 5 volts peak in a burst and all light intensity at once. If instead of flashing 5 volts, one wanted the current to rise lowly from 5 volts to 10 volts each ten seconds, so that the light bulb would be rising in lumens intensity slowly up to ten volts and had its light intensity decreasing to zero volts: my question is what circuit can do that? Somebody like me which knows very little would simply get some LDR's in circle shaped string and with the help of a little motor by means of a periodically rotating shade surely the resulting pulsating voltage would make the lightbulb  grow from zero to maximum slowly periodically yet this approach is for a person with zero knowledge in electronics, I wish I could learn a circuit that could do that without the need of a rotating shade on top of LDR's, any ideas?   What circuit can make a light bulb grows from zero to maximum slowly?A dimmer does the job but is not periodical without the human hand turning up and down the knob constantly.

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• 2 weeks later...

You say: " one wanted the current to rise lowly from 5 volts to 10 volts each ten seconds,"  Is 5 volts off for the lamp?

Also you all say:  "had its light intensity decreasing to zero volts:" That statement is confusing; which is going to zero the light intensity or the applied voltage?

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I AM LOOKING FOR AN OSCILLATOR  OR CIRCUIT THAT COULD MAKE A TAILORED PULSATING VOLTAGE OUTPUT.   I have a circuit that uses voltage to get variable frequencies, but what I need is the reverse, I need an Oscillator or any circuit that can by means of a potentiometer or variable capacitor create a pulsating tailored voltage, quite the opposite of what can be seen in this video: https://www.youtube.com/watch?v=ShI8od3JAec

Dear HarryA and all relevant Electrical and Electronics Engineersin this forum, I have found a number of circuits that will give you HarryA and the relevant participants what I need.  It is a pulsating voltaget that will make a LED or light buld fade in and fade out .One term used though not professional is: NE 555 | slow blink fade in fade out circuit (https://www.youtube.com/watch?v=Xyi6eaRnn9c ). I am clumsly posting the url for this video on youtube.  A second example is the Turn signal running lights which lights some LEDs and keep one lit whcih will help me to achive the pulsating voltage by means of LDR's, yet this approach is not professional, it is better than an LDR on top of an LED that when turned off will drive the voltage to zero, something I do not want, I want a positive voltage sweeping from one to ten volts periodically and this second circuit can help ( https://www.youtube.com/watch?v=8e1S6ynWlqk )

AN OSCILLATOR  OR CIRCUIT THAT COULD MAKE A TAILORED PULSATING VOLTAGE OUTPUT

3:23 / 4:15

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Will the first  circuit here do what you want to do?

I tried it in the simulator but I have not got it to work yet;  poor connection 🤨

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