Electronics

yousmellchinese123
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Re: Electronics

Post by yousmellchinese123 » February 22nd, 2010, 6:00 pm

So then, I spent about most of the day trying to get my photoresistor to work.
I looked at the diagram set by Dark Sabre in the Wiki, and followed it, but it did not work, I was doing it in the light of day and even went in to get a lamp and putting the photoresistor directly beneath it. Any ideas on what I'm doing wrong?
I was using 9 V(6 AA and then I went to 1 9V), I connected the positive side to the photoresistor and the other end of the photoresistor to the motor and directly connected the negative side to the motor.

My guesss is that I'm either paralleling the photoresistors wrong, adding the photoresistors to the circuit wrong, using the wrong wire, or I just suck o-o.

Comments?

LOL, Also, I can't get the electromagnet or the buring of the monfilament to work, I think batteries hate me :lol:
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Re: Electronics

Post by Flavorflav » February 23rd, 2010, 5:51 am

yousmellchinese123 wrote:

My guesss is that I'm either paralleling the photoresistors wrong
In your description of your setup, you don't mention parallel resistors. If you have them, you need to connect one leg of each to one battery terminal, the other leg of each to the same terminal of the motor, and the other motor terminal to the other battery terminal. If it still doesn't work, try a different motor or go to a relay.

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Re: Electronics

Post by yousmellchinese123 » February 23rd, 2010, 7:14 am

Flavorflav wrote:
yousmellchinese123 wrote:

My guesss is that I'm either paralleling the photoresistors wrong
In your description of your setup, you don't mention parallel resistors. If you have them, you need to connect one leg of each to one battery terminal, the other leg of each to the same terminal of the motor, and the other motor terminal to the other battery terminal. If it still doesn't work, try a different motor or go to a relay.
Okay, so a seperate wire for each leg? Sorry about that, I miss alot of things. Thank you.
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Re: Electronics

Post by Dark Sabre » February 23rd, 2010, 3:01 pm

As for the photoresistor parallel'ing:
They don't have + and - sides. The two legs are interchangeable; you can't put a photoresistor in "backwards" in that sense.
You can just twist the legs of the photoresistors together as shown in that picture on the wiki, you don't need a separate wire for each leg of each photoresistor.
Just make sure that the two legs of any given photoresistor are not twisted to each other (if they are you are basically just bypassing it and the motor will run regardless of light conditions).

Assuming that all of your wiring is right, which we can't really check without pictures or something, I'd suspect that your motor or battery is to blame.
How big of a motor are you trying to run off of this? If you are trying to run one of those little 1" diameter hobby motors or something similar, the circuit may not be able to power anything that big. I only tested with that tiny pager motor, but I suspect that you can't use much bigger. The amount of current that the circuit can power the motor with depends on the voltage of the battery, how much current the battery can physically output, the intensity of the light, how close the photoresistors are to the light, and how many photoresistors you have in parallel. The more photoresistors you have in parallel, the brighter the light, and the closer the photoresistors are the light, the lower the resistance across them will be when the light is on. The lower the resistance, the more current can pass through based on V=IR.
You probably have, but also make sure that the battery you are using can power the motor straight up.

As for the electromagnet and monofilament, I think you are using too few or the wrong kind of batteries. The little 9V rectangle batteries are particularly unsuited to electromagnets and nichrome wire. The AA's are on the right track, but you would probably need several sets in parallel to get enough Amp-hours. You might consider upgrading to C or D cells, at least for the electromagnet and nichrome transfers. If you are using nichrome, just use as short a length of it as possible and keep adding batteries in parallel until it works.

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Re: Electronics

Post by yousmellchinese123 » February 23rd, 2010, 5:07 pm

Dark Sabre wrote:As for the photoresistor parallel'ing:
They don't have + and - sides. The two legs are interchangeable; you can't put a photoresistor in "backwards" in that sense.
You can just twist the legs of the photoresistors together as shown in that picture on the wiki, you don't need a separate wire for each leg of each photoresistor.
Just make sure that the two legs of any given photoresistor are not twisted to each other (if they are you are basically just bypassing it and the motor will run regardless of light conditions).

Assuming that all of your wiring is right, which we can't really check without pictures or something, I'd suspect that your motor or battery is to blame.
How big of a motor are you trying to run off of this? If you are trying to run one of those little 1" diameter hobby motors or something similar, the circuit may not be able to power anything that big. I only tested with that tiny pager motor, but I suspect that you can't use much bigger. The amount of current that the circuit can power the motor with depends on the voltage of the battery, how much current the battery can physically output, the intensity of the light, how close the photoresistors are to the light, and how many photoresistors you have in parallel. The more photoresistors you have in parallel, the brighter the light, and the closer the photoresistors are the light, the lower the resistance across them will be when the light is on. The lower the resistance, the more current can pass through based on V=IR.
You probably have, but also make sure that the battery you are using can power the motor straight up.

As for the electromagnet and monofilament, I think you are using too few or the wrong kind of batteries. The little 9V rectangle batteries are particularly unsuited to electromagnets and nichrome wire. The AA's are on the right track, but you would probably need several sets in parallel to get enough Amp-hours. You might consider upgrading to C or D cells, at least for the electromagnet and nichrome transfers. If you are using nichrome, just use as short a length of it as possible and keep adding batteries in parallel until it works.
I see. I'll just try different stuff with the photoresistors until I get it right, I was using one of the 1" motors. I might just put the photoresistor somewhere else to do something else, because I gave up on it and started to do something else. haha.
As for the electromagnet, I went out to get the magnet wire from radio shack and it worked like a charm. Thanks for that tip. :D

Now, on the melting part, that's the part thats bugging me most right now,b ecause I thought it would be just like how you put a paperclip to a battery and it gets hot, but as I did that, it didn't work either, so that part is just ehh.
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Re: Electronics

Post by Primate » February 24th, 2010, 2:29 pm

yousmellchinese123 wrote:I see. I'll just try different stuff with the photoresistors until I get it right, I was using one of the 1" motors. I might just put the photoresistor somewhere else to do something else, because I gave up on it and started to do something else. haha.
As for the electromagnet, I went out to get the magnet wire from radio shack and it worked like a charm. Thanks for that tip. :D

Now, on the melting part, that's the part thats bugging me most right now,b ecause I thought it would be just like how you put a paperclip to a battery and it gets hot, but as I did that, it didn't work either, so that part is just ehh.
Can you get your hands on one of the 6v lantern batteries? Those guys will save your life. Your normal 9v battery just can't push enough current to do anything useful. I had the exact same problem you were having, but as soon as I switched to lanterns everything started working. You'll also want to make sure you've got some nichrome wire--you can find some pretty cheap on Amazon.
Last edited by Primate on February 24th, 2010, 3:57 pm, edited 1 time in total.
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Re: Electronics

Post by zcshiner » February 24th, 2010, 3:05 pm

yousmellchinese123 wrote:Now, on the melting part, that's the part thats bugging me most right now, because I thought it would be just like how you put a paperclip to a battery and it gets hot, but as I did that, it didn't work either, so that part is just ehh.
Get an old toaster and take the heating element (nichrome wire) out of it. If you get a 2 inch piece of that wire, and a 9v battery, it should glow red hot (which is more than you need anyway).

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Re: Electronics

Post by yousmellchinese123 » February 24th, 2010, 4:41 pm

Thanks guys.
I've been asking around for an old toaster from friends now :D
and
I'll get the lantern battery soon. :D
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Re: Electronics

Post by Paradox21 » February 25th, 2010, 2:50 pm

I was thinking about nichrome wire a few weeks ago and I realized that the little wire things I use in chemistry class for flame tests are supposed to be nichrome wire. I haven't bothered to hook one up to batteries because I bought a used toaster. But if for some reason people can't get a toaster, those flame test wires may work.
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Re: Electronics

Post by yousmellchinese123 » February 27th, 2010, 10:46 pm

There is one more question I have, can we have the electromagnet pre turned on before we start the machine?
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