[Lf] Soundcards

[Vittorio De Tomasi]

Hi,

Some questions were raised about sound cards quality in past messages.
At URL http://www.rockpark.com/soundcards/ you can find some
measurements on some brands of sound cards. Maybe they are not very well
suited for Hi-Fi applications, but they look good for ham radio work...

However I think we should look for two improvements in sound card
systems: USB sound cards and 24 bit recording (maybe both in the same
device...). 

A sound card connected to an USB bus should allow us to keep the ADC
very far from switching circuits (CPU, power supply, ...), thus probably
reducing the spurious lines we all see in our background spectra). 

24 bit recording can give us enough dynamic to allow us to switch AGC
off, and to directly digitize IF signals (converted to a suitable IF
frequency) without worrying for saturation.

However I wonder if the market will ever come out with a cheap solution:
we should probably look at USB development systems (like the one sold by
Cypress Semiconductors), and think about wiring a 24 bit ADC to it...


vy 73

Vittorio ik2czl
-- 
*************************************************************************
Vittorio De Tomasi         ik2czl at amsat.org
Home page:                 http://space.tin.it/scienza/vdetomas 
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