A dirt cheap “spectrum analyzer” with an RTL-SDR dongle

Re:A dirt cheap “spectrum analyzer” with an RTL-SDR dongle by scoot on Friday April 18, 2014 @10:56AM (#7609390)

So why not just use an appropriate resistor?

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Re:A dirt cheap “spectrum analyzer” with an RTL-SDR dongle by darkarmani on Friday April 18, 2014 @01:41PM (#7610253)

A resister has a voltage drop related to the current. A diode will always drop the same voltage (within operating parameters).

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Re:A dirt cheap “spectrum analyzer” with an RTL-SDR dongle by nitrogen on Friday April 18, 2014 @01:10PM (#7610073)

The voltage drop of a resistor is proportional to current.

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Re:A dirt cheap “spectrum analyzer” with an RTL-SDR dongle by iiiears on Wednesday April 23, 2014 @03:08AM (#7632589)

So in many appliances the LED serves two functions, Light and part of the active circuit to lower voltage? - This is why HN has for me replaced slashdot and digg. Thank You.

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