How to make LDR Darkness Sensor Circuit Simple DIY

In this video i will show how to make LDR Darkness Sensor Circuit
Asimple science school college project.

BY USING THIS CIRCUIT WE
CAN TURN ON LIGHT IN
DARKENESS
& TURN OFF THE LIGHT IN BRIGHTNESS

ITEM REQUIRED

2) 50KOHM RESISTOR---------1No.

3) 1KOHM RESISTOR---------1No.

5) 9V BATTERY---------1No.

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My Gears :-

[philipdaltons]

I designed something similar to this and managed to get it published in a magazine. My idea I thought up was a "Digital Darkness/Light Measurer". It used a light dependent resistor and a 556 silicon chip, amongst other things, to measure the amount of light or darkness in a room on a scale of 0 to 9, on a digital display. It was published in the "Everyday Electronics" edition of April 1983. I was paid £12 for my work.

[nayyarrashid]

My Uncle who is a radio mechanic made the same circuit in the 80s. He used a power transistor and cut it on the top to make an LDR and he installed the bulb outside in the street. The bulb would go on when the sun set and provide light to passerby at night time.

[EdwinFairchild]

man one full view of the schematic would have been great, some of us dont need to see the wire going inside the breadboard, just a schematic shot for those who can read it and move on

[rupendrasonimat]

Increasing resistance to 2k and exposing LDR to high intensity light worked for me you can also try it
Thank you for the help 😊

[rahimahjofferi]

Its a great and helpful tutorial, thank you! but what if I want to add 13 more 4.5 lumens of LEDs to the construction to make it brighter? Current limit is 25mA Do you mind helping me how the construction is going to be like? For eg. how many more resistors do I need to add and what are the values for each resistor? Your help and response would be more appreciated!

[Red-Feather]

Hi. I made this without a transistor and it works fine. What’s the transistor’s purpose? BTW, everything is connected to the (-) until minute 5:30.

[ishakohli]

This video was really helpful....my physics project was really appreciated 👍👍

[himanshukubde]

I made the same project but it is not working can you tell the reason i make the same connection

[the_jd]

I am planning to make this my first electronics diy project

[mulpurubakthasingh]

bro, for me always led is in on condition

[tommygun]

Hey guys, great video. Are you able to tell me the resistors I'd need to run this off 4.2V please?

[jasonsarno]

It did not work to me. I just notice in the steps that the 1K ohm resistor was first in negative, then later on it was already in positive. please show also your changes next time when making a tutorial.

[hrishavhrick]

I also practice robotics, and I have already made a circuit like that. Mr Innovative is talented, and I liked this circuit of him. But he did a small mistake in the circuit. He has put two 50k Ohm resistor in parallel, which results in 50 k Ohm. Resistance does not add up in series, so he actually set 50 k resistance, not 100 k. He needs to put the 50 k resistors in series to make it 100k. So before making anything, the laws and regulations should be learned first.

[asiantific]

Can i replace buzzer with dc motor? I want to make something move when the laser is cut.

[ewanenkumberamsey]

wow amazing i like the project, but I have tried doing it using 2N2222 transistor but not working

[egothebeard]

I am right if I think I need to switch the 100kohm (2 50k’s ) resistors to one 10k resistor if I want to use a 5 Volt source? And can I use other transistors. I have some PNP transistors.

[krishnatkkb]

Will it work if use 20k r instead of 50k

[practicallab]

its so simple circuit if we connect 100 k resistor with series with ldr it also properly work and if ldr ressitor value in kilo ohm connect mega ohm resistor with ldr it will also work.nice

[gautamchopra]

Request help:-
My LED turns off in darkness.

[aishwaryasajeev]

Mr Innovative.... Can u please tell me whether the method by which you made the LDR is 100% effective or not?? Because many of them in the comment section have said that it is working in the opposite way i.e., the led glows when the light is on... So, by chance if the same happens with me wheni make it, then how can I correct it and make it work in the proper manner??
As I have not tried to make it till now, I want to make sure that this project is 100% successful... So I hope that u would help me in making this project successful by replying to my quarry.
I look forward for your kind and prompt reply.
Thank you.