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[linrad] RE: svgalib works only in VESA mode

Hi Jeffrey,

> I have done the experiment you suggested. I ran svgalib-1.9.19 in 
> both VESA and
> in ATI Radeon modes and found that I could not tell a difference 
> with any of the
> svgalib testing programs or with linrad. Linrad is not graphics 
> engine intensive
> the way a Windows kid's game would require. Also, linrad limits 
> the choices of
> colors to only 256 regardless of the screen resolution. 

I suggest you set the fft1 bandwidth to maximum (800Hz) with a 
sine to power 4 window and deselect the second fft as well as the AGC. 
Set the fft1 averaging to 1 (the box in the lower right corner of
the main spectrum (blue dB scale).
Make the main waterfall cover more than 50% of the entire screen area.

With these settings on my computer, a 2.66 GHz Pentium IV, I get
the following CPU usages for different averagings in the waterfall:

Avg      CPU
100       12%
 10       33%
  3       87%
  2       96%
  1      not possible.

The time is spent mainly with the graphics. This is the kind of situation
when one might expect some difference. It is interesting to look at
the rapidly moving waterfall, many stations have ugly keying clicks
that one can see very well. One can read high speed cw directly off 
the screen:-)  (Press the 'Pause' key or 'G' to freeze the screen)