W3JDR wrote:

Dave,

If you've never heard of 'pink' noise, then you're probably not a student of
noise.

In noise parlance, 'white' noise is the term that is usually used for
non-bandlimited noise (ie, 'broadband noise'). "Pink' noise, on the other
hand, is a term used to refer to bandlimited noise. In practice, anything
that comes out of the audio channel of a communications receiver is really
'pink' noise, as the bandwidth is limited to a few KHz. On the other hand,
the noise that is incident at the antenna or generated in the front-end is
much broader in bandwidth and is more deserving of the term 'white' noise.

Joe
W3JDR


White noise is constant energy/Hz, pink is constant energy/octave.

tom
K0TAR

"W3JDR" wrote in message
news:YUBig.3630$%m5.685@trnddc04...
Dave,

If you've never heard of 'pink' noise, then you're probably not a student
of
noise.

In noise parlance, 'white' noise is the term that is usually used for
non-bandlimited noise (ie, 'broadband noise'). "Pink' noise, on the other
hand, is a term used to refer to bandlimited noise. In practice, anything
that comes out of the audio channel of a communications receiver is
really
'pink' noise, as the bandwidth is limited to a few KHz. On the other
hand,
the noise that is incident at the antenna or generated in the front-end
is
much broader in bandwidth and is more deserving of the term 'white'
noise.
Joe W3JDR


White noise is constant energy/Hz, pink is constant energy/octave.
tom K0TAR

You're both right. The "classical" definition is Tom's. "White" is a
constant energy density. "Pink" is 1/f, which gets to you the octave thing.
In looser circles/ discussions, we often call noise which is not infinite
in bandwidth or not "flat" in the bandwidth of discussion as "colored" and
when the low frequency end has more than the high, "pink" often creeps into
the vocabulary. "RED" noise would be what many broadcast FM stations seem
to be transmitting now-a-days. 15-20 dB bass boost even on the mics.
Really hard to listen to, but liked by the sub woofer crowd we all hear
coming blocks away.

73, Steve, K9DCI

"Boborato"
I wanna know how can I get the FM signal without that
nasty 'pink' noise. I'm not using any kind of external antenna.
________________

An FM receiver needs a certain minimum level of r-f voltage at its antenna
input terminals to meet its noise performance specification. Stereo mode
requires more r-f than monaural, for the same S/N at the receiver output.

No doubt if you use an antenna capable of giving your receiver the r-f input
signal it needs, your noise level will drop to inaudibility (at least with
normal programming).

RF

"Richard Fry" wrote in message
...
"Boborato"
I wanna know how can I get the FM signal without that
nasty 'pink' noise. I'm not using any kind of external antenna.
________________

An FM receiver needs a certain minimum level of r-f voltage at its antenna
input terminals to meet its noise performance specification. Stereo mode
requires more r-f than monaural, for the same S/N at the receiver output.

No doubt if you use an antenna capable of giving your receiver the r-f
input signal it needs, your noise level will drop to inaudibility (at
least with normal programming).

RF

In addition to Richard's comments, many higher quality FM receivers employ a
"muting" switch on the front panel.
The Kenwood KT-8300 has 2 selectable mute settings in addition to off
while the NAD 4020B has a single setting with an on/off switch.

gb

White noise has a uniformly distributed power spectrum.

Pink noise has a spectrum which smoothly decreases in power with
increasing frequency. That is, power is concentrated at the low
frequency (or red) end of the spectrum.

In a narrow band of audio frequencies they both sound the same. There
is no detectable difference between the high and low frequency ends of
the narrow band.

The two terms are usually applied to very wideband communications
systems, ie., from VLF to UHF.

Purely randomly generated noise is described as white. Its
statistical properties are defined as having a Gaussian amplitude
distribution. It is by far the most common natural source of noise.

See Google for the Gaussian Distribution or Function.

It is simple enough : Exp( - x*x ) ).

It occurs throughout Science, Engineering, Medicine, Economics,
Statistics and in all facets of human activities, life on this Planet
and dead materials.

Even politics. It may be said that Blair and Bush lie in the extreme
tail of the Gaussian Distribution. Which of the two tails I have been
unable to fathom.
----
Reg.

See Google for the Gaussian Distribution or Function.

It is simple enough : Exp( - x*x ) ).

It occurs throughout Science, Engineering, Medicine, Economics,
Statistics and in all facets of human activities, life on this
Planet
and dead materials.

======================================

Indeed, it is often referred to by statisticians as the "Normal"
statistical distribution function. Why such a simple function should
be so universal is a matter for conjecture.

Unfortunately, elementary statistics and tossing of dice is a much
neglected subject in our schools. Japanese, Chinese, Korean, Russian,
Indian, Central Asian, even Iraqian, Iranian and Palastinian school
children are probably better educated.

The whole of human life is just a matter of chance. I consider myself
to have been very lucky.

Please excuse my computerised wanderings!
----
Reg.

"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!!


Use an outside antenna

"Jimmie D" wrote in message
.. .

"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!!


Use an outside antenna




Ahhhh! Right to the heart of it, Jimmy...

73, Steve, K9DCI

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!!