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Can anyone make this and post an instructable? Answered

see the schematic and these are the parts and please make a breadboard version

IC1: LM555 Timer IC
Q1: 2N3906 PNP transistor
R1: 100K potentiometer
R2: 3.9 Kohm resistor
R3: 10 Kohm resistor
R4: 47 Kohm resistor
C1, C3: 0.01-µF disc (non-polarized) capacitor
C2: 1.0-µF electrolytic or tantalum (polarized) capacitor
Speaker: 8-ohm, 0.5-watt speaker(i also tried a buzzer)
Photoresistor: I used a LDR aren't they the same?

The buzzer goes off(not off. it's like explosions"The bomb went off") when light hits the photoresistor.

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rickharrisBest Answer (author)2012-09-10

OK I guess you want the BB layout - I don't have time to make the cct but I have drawn a layout for you

Untried but should match your circuit.

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user

there just a faint beep and it exists even if i remove the photoresistor,

and the one you drew doesn't match the schematic because pin 4 is unused in you layout,

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user

Your right missed one - You need to put a wire between pin 4 and the collector of the transistor.

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user
oldmicah (author)2012-09-08

Since you tried an LDR, why didn't you take pictures of what you've done, put in a description of what the circuit is supposed to do, and post it yourself? Alternatively, please give some indication of why you are asking for someone else to assemble it and post it.

The reason i mention it is that people are often leery of posts like this as it often comes across as students posting assignments and asking others to do thier work.

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user

I am an absolute begginner and i know very little and i am not doing it for an assingment i found it in electronics for dummies book

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user

I found it best when I first started to draw the ACTUAL components with ACTUAL pinouts and then connect all the lines

like the 555 timer
8 7 6 5
D |
1 2 3 4

once you've DRAWN the circuit in halfway between a schematic and actual circuit layout, its easy to connect the wires on the breadboard the same as the lines on your drawing. Anywhere there is a dot, there is a connection.

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steveastrouk (author)2012-09-09

What don't you understand about the making process?

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user

i am fairly new to electronics and i just followed the instructions and it doesn't work

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user

Ah.

Well post a few pictures of what you've done, and we can see what it needs/

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user
rickharris (author)2012-09-08

What do you want to know - If it works? Or how to make it?

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user

Doesn't the "for dummies" have instructions??

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user

i followed the instructions but none of the circuits work so i wanted you guys to post an instructable so i get the idea.

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oldmicah (author)2012-09-08

That make more sense: what does the circuit do?

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user

The buzzer goes off(not off. it's like explosions"The bomb went off") when light hits the photoresistor.

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