Help with a Custom Made Launch Controller for G motors / HPR

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I don't know if I'm skipping something really basic or maybe it's something about electronics that I still didn't know but why increasing the resistence for the LED, increase the brightness of it? Shouldn't it be the other way?
 
I don't know if I'm skipping something really basic or maybe it's something about electronics that I still didn't know but why increasing the resistence for the LED, increase the brightness of it? Shouldn't it be the other way?
You’re not missing anything really. For a given LED, increasing the series resistance will typically decrease its forward current, causing it to decrease in intensity. You might be confusing it with more efficient LEDs being able to still be brightly illuminated with higher resistances. Even with them, the same applies.
 
Okay I didn't understand/read it correctly. What you meant is that the resistance of the LED + the original resistors may not be enough to safely use some igniters, that's why it would be a good idea to increase the resistance of R1 and R2. Is that right now? haha
 
I don't know of any commercial igniters or seen any homemade igniters that would only require 20 ma of current to fire.
I believe you are over analyzing this but like I said earlier if you are worried or if it makes you feel safer then use 1K or even 2.2K resistors.
I prefer using super bright LEDs at 20 ma because I can view them directly from Launch Control. This allows me to continuously monitor the state of the igniter before and after the system is Armed.
 
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A general rule of thumb for LEDs is 2.2 Voltage drop or 0.020 Amp ( 20 ma) current draw. It's a good starting point and you can use manufacture specs to refine that.
 
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