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Thank you I'll scrap that schematic, I'll find a new one.
Wow. That LED should be burning very bright if it's passing over 50 mA of current. Is that a carbon comp limit resistor? Now that you know the draw "as is", why not try just upping the limit res? Sounds like a 1K would be worth a try. Metal oxide preferably.Peace,WayneOh, and just want to ask, what color does that LED burn? I would assume yellow for 2.1v, but tech changes so fast......
Just realized we kind of jacked a thread, wonder if you "had to" make a an "unregulated V V" mod, maybe a 555 circuit driving a fet would qualify? Anyone?
Just realized we kind of jacked a thread, wonder if you "had to" make a an "unregulated V V" mod, maybe a 555 circuit driving a fet would qualify?
you can't assume a 2V drop.
Yes, that would be a really easy and efficient way to to adjust an output to some extent. 555 timers are a good way to simply generate a PWM signal and they are 12V tolerant standard. Though it would not be regulated to a specific power level since duty cycle is purely dependent on input voltage and component values. Then voltages vary with battery charge. One note about biasing LEDs, you can't assume a 2V drop. Common indicator LEDs vary from 1.8 to 2.2V depending on current flow. So you really have to verify your bias with a meter. Also 20mA is the limit for most surface mount indicator LEDs. You would typically not want to load one more than 10mA and most are plenty bright at 5mA.