Power an LED with a transistor

hi,

i display signal of dcf77 receiver led. can't provide enough current led.
what works use attiny , put input 1 pin output of another.

i transistor.
this setup (source):


this somehow inverts signal. inverts signal @ output of dcf receiver.

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this somehow inverts signal.

a transistor invert "signal", @ transistor's collector.  but, when input transistor goes high , transistor turns on, pulls-down "ground side" of load , turns on led.   

so, logic high = led on.    normally, i'd say  it's not inverted if logic-high turns led on, depends on how logic works...  if logic-low "active" or "true" state, you'd want led turn-on when signal goes low.

if logic reversed can use 2nd transistor invert again, or can find non-inverting buffer or driver chip.   

don't forget current-limiting resistor in series led.

quote

it inverts signal @ output of dcf receiver.

what?

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