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Discussion Starter #1
Finally! We finished the first in what we hope will be an ongoing series: Electronics Essentials
This first episode covers off LEDs... what they are, how to hook them up and, most importantly, how to figure out what resistor to use to have everything work properly without frying your LEDs. We tried to make it entertaining as well as informative. :)
Let us know what you think. We're open to suggestions!
We've also put together an Excel spreadsheet LED resistor calculator that does all the math for you, as outlined in the tutorial.
Since we can't seem to attach it here, drop us an email if you want a copy.
 

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Discussion Starter #4
Joven76... yes, we are planning to do others. We wanted to see what the response was to this one first. If we get any constructive feedback, we may change things up. It's hard keeping these from getting too dull...
We were tossing around ideas like basic soldering, an overview of different components (like capacitors, diodes, relays, etc). Any requests? LOL
 

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Well Dan, I've seen your other tutorials and I have to say I really liked the way you did this one. I wouldn't mind seeing one about basic soldering techniques. I saw the one you made about wiring tea lights and making sure to tin the wires which helped, but for some reason I tend to overheat the wires and melt the plastic before the solder melts. I may be using to thick of solder though. But never hurts to refresh knowledge.

I do have one question though, in this tutorial, you mentioned if using a 9 volt battery, each time you use a 2.2 volt LED you subtract it from the 9V of the battery. Essentially being able to only use 4 LED's off (1) 9v battery and still using a resistor for the remaining .2 volts, a 10 Ohms resistor. But in your tea light LED wiring tutorial, you mentioned if using a 3v power supply with 500mA, and since it the flickering tea light only pulls about 10 mA, you could power up to 50. So my confusion lies in the math of this tutorial vs. the tea light tutorial. On one hand it appears I'm only allowed to power a certain amount of tea lights based off the voltage, and in the other it's based off the milliamps, or is the math different when using power adapters vs. batteries?

 

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Discussion Starter #7
The difference with the tea lights is all the resistor stuff is done inside the tea lights themselves. Because they are internally controlled with a little chip, all I do for those is drop the voltage they get down to the 3 volts they require, so no current limiting is needed. Instead, I use that constant voltage drop provided by some small diodes (each one drops about 0.7 volts) to basically subtract 2.1 volts from the adapter's 5 volts, leaving me close to 3 volts. Does that clear things up a bit better?
"Recap Tiiiimmmee!!!!" "Let's review what we learned today..." LOL
 

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Funeral Crasher
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Thanks for the video, Creepy!
I know how to solder LEDs, but it's nice to have a refresher course available.

This should be of great help to many haunters!
Thanks again!
 

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Discussion Starter #14
Glad everyone's enjoying it and finding it usefull... that WAS the point. :)
Busy getting ready for the big night, so production on episode 2 will have to wait. Still open to suggestions, otherwise I was going to do one on basic soldering, then one of dfferent components like capacitors, relays, etc.
Exactly one week until the big event, so I hope everyone has a terrific, and safe, time!
 

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Thanks so much for the tech info creepy. You and your Son look like you're having a ball. I think I can extend a big Thanks from everyone that views your productions. Anything you create will be much appreciated by all. I'm learning about RGB LEDs controllers by the smoke test method. It has a unique smell when they flash in their final glory. I assume I need a circuit for control? That's just a suggestion for a future tut. Hope you and your Son have, or had a great Halloween. Thanks Again for taking the time to share your knowledge.
 

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Fantastic job.....very detailed and patient. I'm sure a lot of Forum member will greatly benefit from this tutorial.......thank you!
 

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Mad Monster Maker
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Great tutorial, CC. Awesome information to have. I do have one question, though.

My other hobby is model trains, and I wanted to build a switchboard to control isolated 'blocks' of track. Each block of track would be controlled through a DPDS switch, with a bicolor LED to indicate the polarity of that block (LED would be lit green for "forward" and red for "reverse"). I've seen two types of bicolor LEDs.

First, this one has two leads:

http://www.allelectronics.com/make-a-store/item/LED-6/BI-COLOR-LED-2-LEGS/1.html

Then this one, with three leads:

http://www.allelectronics.com/make-a-store/item/LED-141/5MM-RED/GREEN-BI-COLOR-LED-3-LEAD/1.html

The track runs on 12VDC. I can do the forward voltage/resistor calculations, but which of these LEDs would be best suited to achieve this, and more importantly, how would I wire the resistors so it actually works as expected ?
 

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Discussion Starter #20
The easiest is with the first LED, with two leads. Internally, it has two LEDs (one red, one green), wired in reverse to each other. So, only one can ever light at a time, depending on the polarity of the voltage presented to it. I'm assuming you are using the switch to act as a forward/reverse switch for your block of track, simply by reversing the voltage presented to the track. if that's the case, the two lead LED is perfect. Do your resistor calculation, wire the resistor in series with the LED (as per the video) and connect it across the track voltage. It will either light up red or green, depending on the switch position. If the LED operates "backwards", just reverse the connection to the track voltage. Pretty much foolproof and you should only need one resistor per LED.
 
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Scary Papa
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