F5 - LED

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Are you the same member I commented to earlier today? Do you have a nice resistor in series with your blue (Pass standard) LED? Well, I forgot what's the Vfrwd for blue but lets call it 3V. That's close enough don't worry about it. You want it at your + rail? O.K. don't matter. +25V is across the nice resistor and the 3V Led Cool. Must be 22 volts on the Restsor and 3V on the LED ... yea... How many miliamps do you want on the LED??? 5mA sounds good( do you listen with the lights on???) Sorry. Understand the theory...right you want a 25V rail - the LED (3V) +22V on a nice resistor with R=E/I; 22V/.005=4400 bla bla ohms. So what size is that nice resistor??? Start with a 5k... N.P. uses about 20k??? He must have the lights off...
:2c:
 
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