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

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.

Dave wrote:
Ken Bessler wrote:

"Dave" wrote in message
. ..

Pray tell, in 50+ years of ham radio I have never heard 'pink noise'.

What is it??

SNIPPED


I just used NCH tone generator to make pink noise - sounds
like what you hear on a AM when you open the squelch. I can
email you a sample if you'd like. :-)

Ken



For years we called that 'white' noise or 'background' noise.

Now, with a full quieting signal, 20 uv, if it's being heard on FM I'd
suspect the discriminator or limiter circuits. I'd start looking at the
limiter.



No No No White noise is used where you want an equal distribution of
amplitude across the spectrum you are measuring.

Pink noise is used where you need a response that is similar to the
graph of human hearing for example. It is nonlinear across the bandwidth.

"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

Neat. I especially like the Black Noise...
On Sat, 10 Jun 2006 08:08:24 -0500, "TSnCS" wrote:

http://en.wikipedia.org/wiki/Pink_noise

Then compare to http://en.wikipedia.org/wiki/White_noise

John Ferrell W8CCW

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!!

"John Ferrell" wrote in message
...
Neat. I especially like the Black Noise...

Isn't the mute switch nothing more than a black noise generator?

73, Steve, K9DCI

"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

"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