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building Hackercaps

say it as it is

pfm Member
Complete novice here was going to try and improve my skills by populating some hackercap boards for future use.

seems good practise is to fit led's with resistors, this is where my total lack of knowledge comes in what value resistors and led spec?

also previous Hackercaps have had wire links fitted rather than inductors? what are the benefits or advantages? and where is the best place to buy them to suit the output stage power supply?

The Front end looks simple enough to do as well

only other questions is has there been any updates or known improvements to apply before I build these up?

many thanks
 
I use a standard red or green led in conjunction with a 4K7 2 watt resistor. I often solder leads to one of the LEDs so I can use it as a front panel indicator. If you find the led too bright you can increase the value of the resistor.
 
Yes... but isn't it surprising how much you have to increase the resistance to have a noticeable effect on brightness!
10k will have little noticeable affect
 
I generally put the correct value resistor in for max current/brightness, then a little rotary pot inline to increase the resistance further. You can then dial in the brightness you wish, measure the total value and fit a regular fixed resistor of that value.
 
Yes... but isn't it surprising how much you have to increase the resistance to have a noticeable effect on brightness!
10k will have little noticeable affect

That's because the resistor is limiting the current to the LED rather than dropping the voltage. The voltage across an LED is reasonably constant across a wide current range or something like that!
 


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