DIY Night rig the easy way

[gergob@gmail.com]

DIY Night blades discouraged me for a long time for 2 reasons. 1: I did not want to solder and glue tiny LED's and regulators directly to the surface of the blade. 2: I gave up on trying to find the right resistors and LED's on various electronics websites. Having said this I believe the solution I'll show you guys here is one of the most simple one, while offering good redundancy for safety. I begun night flying with RotorTech 710 Luminous V2 night blades and 420 LEDs from led strips the LHS carries. This setup was great but I wanted more. I bought the RotorTech 105 night tail blades (lucky I have a 700E since they don't make it smaller) and I finally decided to add extra LED's to my RotorTech main blades because I wanted more blue and green circles .

Here is a very simple way for DIY main blades:
First off, clear coat the blade once or twice, especially the leading edge. Exposed carbon fiber will drain your battery. Let it dry overnight.
Look at the LED strip from pic0431. This is the normal LED strip my LHS carries, they are very common. They are designed for 3S lipo and have 131ohm resistor for green and blue. I'm not gonna get into different colors and resistors here. I use these LED;s on my main blades. Look at the middle strip. I cut the strip short by cutting 1 led off, and I removed the resistor.
I took the middle strip and used in on pic0415 by soldering the copper strip on top of the led strip. This LED strip can then be glued and folded on the leading edge of the main blade. pic0428 and 435 shows you the the final product. - is running on top of the blade and + copper strip on the bottom. If you want different colors on top and bottom of the blade you'll have to solder and swap a green and blue led: Pic0417- Pic0418.
Pic436, 433 and 430 shows where i placed the resistor. It's on the bottom of the blade on the + side.
My rotortech blades have the built in battery, I decided to use a separate circuit for the added leds. I now have 2 batteries/ blade (pic430). Either system fails my main rotor will stay illuminated. I did one test flight tonight, will do more tomorrow. All I can say is the extra wind resistance from the height of the battery is unnoticeable. This is pretty much it for building the blades, lets now discuss the planning that goes behind all this.

If you're going to try my design be prepared to run it on 2S lipo and not 1S. Reason being these LED strips are designed for 3S and they are connected in series. 1S lipo does not have enough power even without resistors to fully light up 2, let alone 3 LED's in series. If you want to use a 1S lipo, you can (pic 411) with the right resistor, but you have to solder the led's in parallel, meaning you have to take the LED's off the strip and glue them to the main blade.... There are plenty of tutorials for that already. The upside to my method is that you don't have to worry about gluing/soldering LEDs, you're only gluing the strip in place.
There is one more thing I need the mention, on pic415 you can see that the copper tape goes over both the + and - terminal of the strip. If you look at the strip carefully, the - wire runs on the side of the strip from end to end. Since i cut 1 led off the strip, the - pole only surfaces once on the strip. You can solder over both terminals without shorting anything. You'll understand when you look at the strip, it's difficult to explain.
Lastly, let's talk about those dreaded resistors.
http://www.hebeiltd.com.cn/?p=zz.led...tor.calculator is all I used to figure out my setup. I'm only going to discuss blue and green LED's now. Reds but I've seen yellows and white LED's that run off 2.X volt while green and blue use 3-3.1. When selecting colors, if you want your setup to run off 1 resistor only pick the led strips that have the same resistors on them. Blue green use 131 ohm. Red, yellow and white in my LHS have 331Ohm resistors. For the online calculator you'll need some specs from these LEDs. These strips have 3 leds in series, they are designed for 12.6V and have a 131 ohm resistor. This tells you that 12.6V/131OHM=0.096AH since there are 3 in series, divide by 3 and it tells you that the stock setup is designed for 30mAh. I used 30 as the starting point for my Desired Current. As far as Voltage Drop across LED, i plugged my 400 leds into 12.6 volt and measured 3V on the 2 sides of an LED i picked randomly. This tells you that you need 3V forward voltage for this particular led. I recommend getting that 500 pack resistors from Radio Shack for $13, it gives you more resistors then you'll ever need. By trial and error i got stuck with a 100ohm for my setup. 8.4V input, 3.1V voltage drop across led, 24mAH current for 2 LED in series yielded 91OHM, next size up resistor is a 100 (leds in series calculator)... My setup has 2 strips connected in parallel, and each strip has 2 leds connected in series. It has enough current to run half dozen more parallel strips if I wanted to. As far as running time, I left both blades running for a good 30 minutes, the 4 leds brought my 2S battery down from 8.4 to 8.15V. I should have a good 2 hours on them.

[gergob@gmail.com]

Here is another blade I made last night. This blade was used for night flying before, but it wasn't very bright. I pulled old copper tape off of it and redesigned the circuit. I've been wanting to try 2 LED's in parallel sitting behind each other for a while.



Much brighter than 2 single green led's on an other blade.



1S battery followed by 1OHM resistor on the inside of the blade, 8 blue/green leds, 10OHM resistor and 4 red leds. The blue/green run 3.2V and the red is at 1.98V. I made this for a friend, he will clean up the resistors and make the 2nd blade according to this one.


From 160mah hyperion 1S it has a 16 min runtime.

[maarset]

Yes it's ingenious! (The Friend).

It's such a hassle to solder all those tiny resistors to each LED. Can't wait to try them out.