LED Light and a Save
05-14-2017, 03:24 PM
#1
Thread Starter
LED Light and a Save
A while back I decided to add an LED light to my SPAD airplane just so it indicates when the plane is live. Works good; switch on = LED on. So today I was preparing the plane for, hopefully, flying tomorrow. I started charging, turned on receiver to check for red light. Then I went to other projects while it charged. Once charge was completed I disconnected and began charging my starter battery. I picked up the plane to store it on its cradle and to my surprise the LED was on. I had forgotten to turn the switch off. So my first save with my little LED light. Yeah.😀
05-21-2017, 05:06 AM
#3
Thread Starter
Thanks John. I had a free channel on my receiver so I connected there. I have to say the pictured LED is not the right one for this purpose. It was just a spare I had. This one mounts, from the outside, in a hole in fuselage then you add the lock washer and nut on the inside. So I had to solder the dropping resister then feed it thru the hole then secure it with the nut.Then I had to solder the wiring inside the fuselage. A little bit of a pain.
Going to to try to post 2 pictures. I've been having a problem doing that since the program change. The first just shows the LED on. The second is the LED type better suited for this purpose. You can do all your wiring outside the plane. Then drill a hole, install the LED and secure with Goop Adhesive. I'm finishing up a build now. Will try that tube type LED.
Well I still cannot post 2 pictures in a post.
05-22-2017, 07:36 AM
#5
Ah ha, thanks for the response and picture effort guessed you were using an open port but was wondering about the voltage for the leds. Have used many of them but always in long strings for nite flyers with a separate battery but this idea is a brilliant solution of yours for a pesky problem I have for three of my controlline airplanes.
The majority of my RC aircraft I normally use a push/off external switch and forgetting and leaving a switch on is not a big problem since a glance at the switch reminds me. But on the three Ukies all are throttled (RC) engines using 2.4 RC for throttle control. All use little bitty 50 or 270 mah packs that are in hatchs and I avoid the weight of a switch by plugging directly to the RX. Just leave them plugged in all day and unplugging at end of day but here is the rub: I can't count how many of those little packs I have destroyed by forgetting at the end of the day since there is nothing visual. Sometimes discovering it only months later!.
I suppose it could be argued that Voltwatch gadgets do the same but they are expensive and also so darn big (butt ugly)!
Am working on them now with your permission, just a single led buried under a tiny hole where I can look to remember if I unplugged or not.
Thanks
John
The majority of my RC aircraft I normally use a push/off external switch and forgetting and leaving a switch on is not a big problem since a glance at the switch reminds me. But on the three Ukies all are throttled (RC) engines using 2.4 RC for throttle control. All use little bitty 50 or 270 mah packs that are in hatchs and I avoid the weight of a switch by plugging directly to the RX. Just leave them plugged in all day and unplugging at end of day but here is the rub: I can't count how many of those little packs I have destroyed by forgetting at the end of the day since there is nothing visual. Sometimes discovering it only months later!.
I suppose it could be argued that Voltwatch gadgets do the same but they are expensive and also so darn big (butt ugly)!
Am working on them now with your permission, just a single led buried under a tiny hole where I can look to remember if I unplugged or not.
Thanks
John
05-22-2017, 09:59 AM
#6
Thread Starter
I'm no expert when it comes to things electronic. But there is a formula and some online calculators that determine the resistor value needed for the voltage in use. I had the specs for this LED and just figured the resistor needed for my 6.6V Life Battery. I tried to find the link for the calculator but it is hidden somewhere in my iPad. If I find it will post a link.
I'm constantly checking that airplane on-off switch so thought a light would help. I have some slide switches and push- pull switches. I just forget which way is on or off. A light solves that problem. I've used LED indicators in other applications. Good luck.
I'm constantly checking that airplane on-off switch so thought a light would help. I have some slide switches and push- pull switches. I just forget which way is on or off. A light solves that problem. I've used LED indicators in other applications. Good luck.
05-22-2017, 02:56 PM
#7
Thread Starter
Hi John. I found this calculator that will give the resistor value for a single LED. When you buy the LED, the package should give you the forward voltage and forward current. So put these values in the calculator plus the source voltage you are using. It will give you the resistor value for the circuit. Note LED is polarized so the longer leg or pin is positive, shorter is negative. I place my resistor on positive side. I also use 15ma for forward current. This gives a low power glow of the LED. Red and green are low power. Bright white is high power LED. If you can't fine the resistor value for the circuit, use the next higher value available. Example for 120 ohm resistor value use 150 ohm. Hope this helps.
CALCULATOR
CALCULATOR
