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Old June 13th 06, 08:53 PM posted to rec.radio.amateur.antenna
Steve N.
 
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Default FM without 'pink noise'

OK here's my take, since all the other answer'ers answered without having
enough info in the first place, in my opinion...

Pink niose explanatino #12.
What you call the "pink noise" that you see / hear in an FM receiver could
be that which is designed into the receiver and therefore not normally
removable. You could add preemphasis to "whiten" it up. The reason is that
the receiver has "de-emphasis" built in to compensate for the pre-emphasis
designed into the transmitters that it will receive, which, in turn, was put
there to help enhance the low noise characteristics of the FM mode of
transmission. This "de-empnasis" is nothing more than a filter which
reduces the high frequency audio copmponents more than the low frewquencies,
thus giving it the "pink" or low frequency enhanced characteristic. The
term Pink coming from the color red which is the color of lower frequency
visible light and we have simply retained that analogy when referring to
noise. Narrow band receivers use a simple -6 dB per octave deemphasis
across the whole audio band and wide band, broadcast receivers use something
similar, but it doesn't extend across the whole audio band.

So can you be more speciffic?

When do you hear this noise?
Why do you want to get rid of it?
What are you listening to?

73, Steve, K9DCI



"Boborato" wrote in message
...
Hi group.

I wanna know how can I get the FM signal without that nasty 'pink' noise.

I'm not using any kind of external antenna.

Greetings!!