🚀 go-pugleaf

Here is the summary of the responses on how to get a 
better FFT plot.

1. Wind tunnel should be stable.
2. Use windowing.
3. Put the hot-wire out of the wake of the cylinder.
4. Use and improve analog anti-aliasing filters.
5. Sample at at least 10 times the expected frequency.
6. A good reference on windowing: " On the use of windows for
   harmonic analysis with the discrete fourier tranform",
   Proc. of the IEEE, vol 66, no 1, jan 1978.

7. Instead of the FFT try the "max. entropy spectra"
   method - Numerical Recipes has a write-up.

8. My own: read the ILS software manual again !!!


I hope this meets the requests of some people. 


Once again, my THANKS to everyone for their great help
and interest.  My apologies for posting this summary so late.

Good bye

-- 
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Jamshed Perwaiz                      |perwaiz@engrg.uwo.ca
Department of Mechanical Engineering |perwaiz@gfx.engga.uwo.ca  
The University of Western Ontario    |