1. I'm a nerd.
2. I wanted citrus plants but I live in an apartment with horrible "sunlight accommodations" in Iowa City, Iowa. Citrus plants require a lot of sunlight and this week alone it's been cloudy almost every day.
3. I live in a college town so anything left outside either gets stolen, broken or thrown up on so growing them inside is a must.
Those are my reasons, maybe you have a few of your own but before going any further I must say that if you're going to use this information to grow pot I will not be held responsible for your drug habits if you are caught. Like I said, I'm using this to start up my lemon, grapefruit and orange seedlings, which last time I checked was perfectly legal.
Oh and one of the battery terminals I used came from the design by xtank5:
thanks for that idea too!
Step 1: Materials
25 x red LEDs (cheap ones off ebay, **see bottom for important details**)
5 x blue LEDs (same)
2 x ferrite beads
2 x 1K resistors
2 x 2N3904 transistors
28 gauge wire and some much thicker scrap wire that was lying around (the thicker wire is not necessary)
1 x perf board
1 or 2 Liter bottle
A gatorade bottle
electrical and clear tape
Soldering iron and solder
Wire stripper (was helpful)
Knife or razor blade
Brain (also helpful)
**LED Info: According to Wikipedia, chlorophyll a & b absorb light at maxima of:
430nm & 662 nm for chlorophyll a
453nm & 642 nm for cholorphyll b
So make sure that you find blue (440490 nm) and red (~625-740 nm) LEDs that are as close to those maxima as possible!
Also, you will notice that there are many more red LEDs than blue ones, this is because I read that red LEDs are more important for flowering than blue LEDs (I was corrected, blue is for growth and red is for flowering) and many people are completely successful with red LEDs alone. Whatever you do, don't waste your money on green LEDs because that wavelength is not absorbed!
Step 2: Assembling the Joule Thief Circuit
Since, I don't know how to do a real wiring diagram this one will have to do. I apologize for all the crossing wires, but it should give you the common person's idea of how it is set up. The wiring colors probably look like I'm hooking up a car stereo with all the purples, blues and yellows but I was just trying to keep people from getting confused when the wires are crossed. The colors are not important, just so you can distinguish between the wires.
Basically we will expand this to have 5 Blue LEDs in one joule thief circuit and 25 Red LEDs in another joule thief circuit. All I can say is make sure your Emitter (E) leg of the transistor goes to the (-) of your battery and LED, the Cathode (C) leg goes to the (+) of your battery (through the ferrite core) and LED, and the Base (B) leg goes to the (+) of the battery (through the ferrite core). Also when looking at the transistor the lettering goes E B C from left to right when you are looking at the side that has the writing on it (so the side that says "2N3904" is the side that has E B C from left to right). Practice with one LED first to make sure it works!
Ultimately, I made two of these circuits for my design
Step 3: The Board
Image 2: This will probably be the most helpful to you of any of the 3 pictures here. Again, the colors are not that important, just note the purple is (+) and green is (-). Also, to avoid confusion the blue LED circuit wires are a little lighter than the red LED circuit wires. The wires come off of the board so that you have (+) and (-) wires for your joule thief circuit 1 (red LEDs) and joule thief circuit 2 (blue LEDs). If you look at step 2 again you can see where purple and green wires connected to the (+) and (-) ends of the LED right? Well, since you made two of those joule thief setups with separate ferrite cores, transistors, etc. you will hook up one setup to the (+) and (-) of the red LED circuit and the other to the (+) and (-) of the blue LED circuit as seen in the diagram below. Hopefully, this makes sense.
Image 3: I guess I will show you the back of my board where I wired everything, but really don't pay attention to it because it looks HORRIBLE (yet amazingly it doesn't short if it gets shaken around a little). You will probably learn nothing from this picture except that I should never design major roadways. Make yours better than mine.
Step 4: Battery Holders
Image 1: This first image shows how I made a battery terminal using xtank5's design, it's simple and again I will leave you to the original instructable for it.
Image 2: This second battery holder was made out of a pill bottle I found lying around. Basically, a hole in the lid for the (+) wire that connects to a piece of aluminum foil, then batteries (3 in this case) and a piece of foil at the bottom that is connected to the (-) terminal, which is supported by some small pieces of folded cardboard (to make it somewhat "springy").
Step 5: Focus! Daniel-san...
Step 6: The Planter
I used an old t-shirt that I cut into strips and used them to "wick" the water to my plant. The image below is fairly self explanatory. Since these will one day be lemon TREES, I can't keep them in there forever but for now it has been very useful in keeping my plants watered.
** It is helpful to wrap the container with something like old newspaper so that light is not shining on your water very much, to keep down the growth of algae. **
Step 7: Plant Stuff!
I hope you enjoyed this instructable and vote for me in the contests if you liked it!
If you have any comments or questions feel free to leave me a message below!