On 3 Jul 2007 03:44:57 gmvoeth@....... wrote:
Winquake needs a FFT  waterfall display to see a movie like of shifting 
frequencies over  time.
Possibly in 1024 sample chunks advancing one sample for the next  1024.
Nothing fancy, Black and white and shades of gray,  totally  suitable.
 
Hi Geoff,
 
  WinQuake does not have a waterfall display, but it does have a  useful 
procedure for viewing a scanning spectrogram. Here is how:
 
(1) Set "X Scale" to the time interval window you want to use for an FFT.  
You will get a slider button on the bottom of the screen which will allow you to 
 view any portion of the event record.
 
(2) From the menu bar, select "Calculate", "FFT...", "View Only". An FFT  
plot will appear.
 
(3) From the menu bar, select "Window", "Arrange". You can then  
simultaneously view the windowed event data and the FFT for the window.
 
(4) Use the slider button to scan through the file. As the event data  slides 
through the window, the FFT display will update almost continuously to  
display the spectrum for the data displayed in the window. (Unfortunately, the  
scale for the FFT may change as well.)
 
Bob
PSN Station REM
Locust Valley, NY



************************************** See what's free at http://www.aol.com.





On 3 Jul 2007 03:44:57 gmvoeth@....... wrote:
Winquake needs a FFT=20
waterfall display to see a movie like of shifting frequencies over=20
time.
Possibly in 1024 sample chunks advancing one sample for the next=20
1024.
Nothing fancy, Black and white and shades of gray,  totally=20
suitable.
 
Hi Geoff,
 
  WinQuake does not have a waterfall display, but it does have a=20
useful procedure for viewing a scanning spectrogram. Here is how:
 
(1) Set "X Scale" to the time interval window you want to use for an FF=
T.=20
You will get a slider button on the bottom of the screen which will allow yo=
u to=20
view any portion of the event record.
 
(2) From the menu bar, select "Calculate", "FFT...", "View Only". An FF=
T=20
plot will appear.
 
(3) From the menu bar, select "Window", "Arrange". You can then=20
simultaneously view the windowed event data and the FFT for the window.
 
(4) Use the slider button to scan through the file. As the event data=20
slides through the window, the FFT display will update almost continuously t=
o=20
display the spectrum for the data displayed in the window. (Unfortunately, t=
he=20
scale for the FFT may change as well.)
 
Bob
PSN Station REM
Locust Valley, NY


See what's free at AOL.com.