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Lightsensing with timer.

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besomuk

New Member
Hello everyone.

I need to make some kind of cat alarm which will work in complete darkness.
So , i'm searching for circuit which can sense movement, and then turn light for about 1-2 minutes, and then turn it off.
I'm planning to do this with photoresistor and IR diode, which will be the trigger, and 555 which will be the timer.
So, does anyone have some schematics similar to this one?
 

ericgibbs

Well-Known Member
Most Helpful Member
Hello everyone.

I need to make some kind of cat alarm which will work in complete darkness.
So , i'm searching for circuit which can sense movement, and then turn light for about 1-2 minutes, and then turn it off.
I'm planning to do this with photoresistor and IR diode, which will be the trigger, and 555 which will be the timer.
So, does anyone have some schematics similar to this one?

hi,
My home security lights are triggered by cats, upto about 5 mtrs range.

A standard PIR sensor would do the job.:)
 

besomuk

New Member
Unfortunately they dont have it in my local shop, and i need this urgent...by tonight :)
Actually, i'm looking for my runaway cat, and i think i found place where is she.
Only access to that place is through hole on glass doors about 25cm width.
I'm planning to put my laptop with modified IR webcamera inside, trigger on entrance, and make them send me email (and record short movie) when motion occurs. Problem is very very low light, so web camera does not see anything.
Solution one is to make IR reflector, but i'm not shure how much power i'll need to power it all night...
Second is to make circuit from first post, and power IR ore regular light only when cat passes through that hole.
 
Last edited:

ericgibbs

Well-Known Member
Most Helpful Member
Unfortunately they dont have it in my local shop, and i need this urgent...by tonight :)
Actually, i'm looking for my runaway cat, and i think i found place where is she.
Only access to that place is through hole on glass doors about 25cm width.
I'm planning to put my laptop with modified IR webcamera inside, trigger on entrance, and make them send me email (and record short movie) when motion occurs. Problem is very very low light, so web camera does not see anything.
Solution one is to make IR reflector, but i'm not shure how much power i'll need to power it all night...
Second is to make circuit from first post, and power IR ore regular light only when cat passes through that hole.

I see.:)

Does your laptop have camera software that can detect the change in a scene, movement detection.?

If you use about 6 or so IR led emitters, you should be able to 'see' the cat with a PC IR camera, especially the eyes.

For the 'hole' you could use a IR emitter and IR detector as beam break detector.
 

besomuk

New Member
Does your laptop have camera software that can detect the change in a scene, movement detection.?

Yes, that's not a problem.

If you use about 6 or so IR led emitters, you should be able to 'see' the cat with a PC IR camera, especially the eyes.

I know, that's why i'm considering that option instead of visible light...i think it might get scared and run away...

For the 'hole' you could use a IR emitter and IR detector as beam break detector.

Ok, but how to keep emitters on?
 

ericgibbs

Well-Known Member
Most Helpful Member
I know, that's why i'm considering that option instead of visible light...i think it might get scared and run away...

Ok, but how to keep emitters on?

I agree the visible light may scare him off.

Do you have a small power supply, say 12V dc output rated at 1amp.?

If yes, you could drive the IR emitters from that, using a suitable series resistor.
 

ericgibbs

Well-Known Member
Most Helpful Member
I'm not shure, i'll have to check when i get back home...If yes, that would be easiest solution :)

Lets know the psu voltage and details of the IR emitters and we can suggest resistor values.
 
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