I was looking forward to flying the Mcfoamy at last weeks domefly with my newly installed lights. As I mentioned previously, I used a converted servo connector to allow me to run 8.4v right off my 2 cell batteries balancing tap. This was an easy and lightweight way to run the lights, and while not as bright as running off of 12v, it was good enough. The problem showed itself right after takeoff. While the yellow wingtip lights were working fine, the violet taillights weren’t on. I figured that something had come disconnected, so I landed for an inspection. I then found that the lights were back on. My buddy Jason was having the same problem with his identical setup, and noticed that they went dim and then out as throttle was added. Apparently, the batteries voltage drops far enough under load from the motor that the violet LED’s go out, and then come back on as soon as the motors shut off.</p>

I’m guessing that the LED’s spec’s of 6 to 12v are nominal, and that the violet ones actually need more than 6v to light up, while the yellow ones still work fine. I have taken a look at the wiring on the LED’s, and found that they are wired three at a time in series with a small chip inline that I belive is a diode. Knowing that LED’s have no electrical resistance of their own and the diode is normally added to keep the circuit from acting like a dead short, I thought at first that I might be able to bypass the diodes and add an appropriate resistor to feed the whole circuit. Some probing with my multimeter however showed a voltage drop across each LED, indicating that there must somehow be a resistor in each LED junction. This makes any ” quick and easy ” solutions impossible.</p>

I will be instead be taking the easy way out and just swap out my violet LED’s for more yellow ones.</p>

Dean</p>