Hi.

A DSP filter can do this to a degree, but it generally introduces 
distortion into the intended signal, because in order to remove the random 
noise frequencies, it is inevitably also removing a little of the intended 
signal, giving it a kind of watery sound.  I have used DSP filters for 
about ten years, and there are times when they are handy, but they are 
definitely not the be all and end all, and there are times when I actually 
prefer a good crystal filter to a IF level DSP filter.  Just goes to show 
that there is no one perfect solution to those unwanted signals and noise 
sources.

73, de Lou K2LKK



At 10:16 PM 2/5/2006 -0800, you wrote:
>Hi
>A few years ago I had an idea for a filter that would remove the back ground
>noise on HF.  I was wondering if a digital signal processor does this or if
>some one had made a commercial filter to do this.
>     It would be a help to catch those stations that fall below the noise
>level!
>                     God bless,
>                     Mark WZ0K
>God loves you!
>My personal prayer book.
>Add your prayer or pray for others at the following link.
>http://prayerbook.homewithgod.com/cgi-bin/prayerbook/multi.pl?131961113534708:24:0
>
>http://lists.topica.com/lists/funhamradio.
>
>http://funhamradio.bloki.com

Louis Kim Kline
A.R.S. K2LKK
Home e-mail:  [log in to unmask]
Work e-mail:  [log in to unmask]
Work Telephone:  (585) 697-5753