## Step 4: Solder the Resistor to Positive Terminal of the Battery Clip Like Shown in the Photo

<p>Nice Button!</p>
I've been told that if you wire it in series it'll still only use 20ma but wiring them in parallel it'll use 60. but since you have 9v to play with it would be smarter to use 3 white leds with no resistor. most white leds are 3v.
See my sensor version! (Click my name to see my My I'bles)<br> <br> --------------------------------------------------------<br> &quot;May the good belong to all the people in the world.<br> May the rulers go by the path of justice.<br> May the best of men and their source always prove to be a blessing.<br> May all the world rejoice in happiness.<br> May rain come in time and plentifulness be on Earth.<br> May this world be free from suffering and the noble ones be free from fears&quot;<br> ---- Vedic blessing<br> <br> <br>
great idea men, thnx
indeed a great beautiful project, compliments, has estimated it the maximum, I adores the minimalistic inventions, has realized instructable a much similar one to yours, that mine it is a portable usb charger a not torch, but the small torch is however much pretty one, very good!
Hey gud instructable, I made a version of this mixed with YAN9VUSB instructable so it's housed inthe outside of a 9v battery! heres some pics
Nice Instructable. I especially like your drawing in step seven, very detailed. I wish more people could learn to draw like you rather than a puddle of color made in paint that "illustrates" how to build a car. :)
Wait.... why do we need Blu Tack?
as helping hands
can i use a 1/4 330 ohm resistor?
Use the calculation below to calculate an appropriate resistance
im going huge with this more LED's!!!
hoe much Ohm is that resistor?
330
This circuit is a LED and a resistor in series, lets say you have an high intensity LED, 3.4V 20mA. the resitor would have to have a voltage drop of (9-3.4) 5.6V, we then use ohms law to calculate the resistance. <br/><br/>R=V/I<br/>R=5.6/0.02 0.02= current through series circuit<br/>R=280ohm<br/><br/>If you want a brighter light just decrease the resistance a bit to that of your calculated value, generally this wont harm or shorten the life of the LED as the stated value for max current is usually lower than tollerant<br/><br/>hope that helps<br/>
for the cellphone battery emergency light..you could build some form of "clip harness" type deal that the cellphone battery could fit into with the led/resistor combo could be built into...so you could keep it in your bag...and in an emergency you just pop the battery out of your phone and stick it in the clip deal...thus making it work for the light...but you'd also still be able to stick the battery back into your phone for charging it..
This step is a little harder than it seems. I've ruined two of the battery clips lower halves by trying to pry off the bottom. It seems like it is really attached on there well. Anyone have any tips on prying off the lower half.
Try using the tops (with the clips) from old 9 volt batteries. they are relativly easy to remove.
This may even be combined with this Instructable - <a href="https://www.instructables.com/ex/i/E16CE8EC32081029BC6B001143E7E506/">https://www.instructables.com/ex/i/E16CE8EC32081029BC6B001143E7E506/</a><br/><br/>I may try it tomorrow.<br/>
Hey thats not a bad idea. It might be easier to fit it all together.
Hey thats not a bad idea. It might be easier to fit it all together.
i soldered another wire parallel onto the negative led. this seems to make it somewhat stronger
Nicely done! I want to make one of these. What did you mean by "strengthen the negative lead of the LED"? How do you do that?
I didn't quite answer your question yet. well the higher the current used by your circuit (resistor and LED in series) the shorter it will last. So get a high efficiency LED that will lengthen how long the battery lasts
Yup. First you have to figure out how many milliamps per hour your battery supplies. unfortunately this is not written on most normal batteries. But fortunately most rechargable 9V batteries are similar to non rechargable 9V batteries. Most rechargeable ones supply 150mAhr. Soooo. all you have to do is measure the current leaving the battery when its turned on and divide 150 by that number. (make sure you always work in milliamps). and that gives you your answer in hours. Well anyway thats how i think its done
Any idea how different LEDs effect how long the battery lasts?
I also remember seeing a commercial version of this with two different light settings. I bet it would be difficult but not impossible to do on your own. This is a rly great money saving project. I will attempt it eventually.
I added an extra picture to step (7) with a diagram of all the components in the battery clip. I hope that help you wisepig
awesome! thanks for the diagram -- I just went out and made one!
Yeah for this you could use different types of batteries to make the light smaller. I guess the cool thing is that large batteries like 9V and AA, AAA batteries can supply alot of current and therefore the LED will go for ages. but since batteries are getting smaller and last longer it would be very cool to use something like a cellphone battery. But you have to remember that the point of this torch is so that you can put it in a wallet or some emergency pack and buy the battery for it later when you need it. otherwise you might aswell by a LED keyring torch
This and the Tic-Tac light have given me some ideas. To get smaller/simpler, consider using a 3.7v Lithium ion cell from a small digital camera. My Pentax Optio uses a battery (D-L 18, and NP-40) that I was able to buy for \$8.00. That is readily available via Ebay or Amazon third tier sellers for cheap. These wouldn't require a resistor either, but would require some ingenuity to attach the bulb/switch to the pack. I'd recommend using whatever you have a charger for. There should be many cellphone battery possibilities as well. Correct me if I'm wrong, but you should be able to connect more bulbs in parallel and get a brighter light.
You could just solder wires to the battery contacts, thing is phone batteries often have 3 or more terminals, so you'll need to test it.
Yes, but it might not fit back in the charger if you do so. PDA battery packs are another possible surplus score. Electronics Goldmine has a Handspring pack on sale now for \$5.
WOW shite what did I just do
I used a small LED to make it easier to put it all together. Of course you could use a 25mm LED but you might have to glue the LED on top of the battery clip because it will not fit into the clip. The LED i used was a normal 1.5-2 V LED that requires a resistor in order to run without blowing up. If 9V LED's are available that would make the job a hell of a lot easier but maybe more expensive. When i started the project i was thinking of using a flexible/soft LED snap. I would have done all the wiring like in the one above and then covered the whole thing in hot glue to wathever shape i wanted and then spray painted it. I think it would look quite cool
I used a small LED to make it easier to put it all together. Of course you could use a 25mm LED but you might have to glue the LED on top of the battery clip because it will not fit into the clip. The LED i used was a normal 1.5-2 V LED that requires a resistor in order to run without blowing up. If 9V LED's are available that would make the job a hell of a lot easier but maybe more expensive. When i started the project i was thinking of using a flexible/soft LED snap. I would have done all the wiring like in the one above and then covered the whole thing in hot glue to wathever shape i wanted and then spray painted it. I think it would look quite cool
I used a small LED to make it easier to put it all together. Of course you could use a 25mm LED but you might have to glue the LED on top of the battery clip because it will not fit into the clip. The LED i used was a normal 1.5-2 V LED that requires a resistor in order to run without blowing up. If 9V LED's are available that would make the job a hell of a lot easier but maybe more expensive. When i started the project i was thinking of using a flexible/soft LED snap. I would have done all the wiring like in the one above and then covered the whole thing in hot glue to wathever shape i wanted and then spray painted it. I think it would look quite cool
There is just one problem with glow in the dark paint. the LED will not shine much light to the side as most LED's are made to focus. But maybe a little paint just around the LED would work. Thanks for the cool idea
What 25\$ for a Pac Lite!!? Man awesome work I'd rather make my own than pay 25 bucks for one.
great project but i don't fully understand the switch. how does it work?
is it a 9v LED or any kind? is it imposoble to use a soft 9v snap or just harder
You could look into buying some glow in the dark paint, I think Humbrol do it in small 22ml pots ? I was thinking of using 2 5mm super bright white LEDs, mmm bright ...
One cool thing I must add about the PAC LITE is the white plastic it uses which is in fact glow in the dark material. just thought i might add that.