Hallo Alberto, You know the circuit with the 555. It has a frequency of 15 kHZ at 6 Volts. There are two outputs with each +/- 90° phase difference. Round about 100 mV.
I think, the screens are understandable for You. 1. ... test of stereo or mono (most laptops have only mono on micro-in. 2. ... Anti-Aliasing Filter is absolute necessary for I/Q. Most of cards do have only a very soft filter for higher frequencies. 1. screen: good soundcard USB 24 bit. 2. screen: very bad card with a lot of reflexions of the basically 15 kHZ. 3. screen: Mono only 4. screen: Mono without filter on the card 5. screen: Example of Creative Soundblaster Audigy 4, on one of my computers. I think: The main thing is to have some nice and relatively easy test circuit, which is not so expensive and together with SDRadio a nice tool. I think, that there could be a kit or ready built circuit by AK-Modul-Bus. Burkhard understands English. [EMAIL PROTECTED] Wolfgang Hartmann --- In [email protected], "i2phd" <[EMAIL PROTECTED]> wrote: > > --- In [email protected], "Wolfgang Hartmann" > <dadalbinder@> wrote: > > > > A simple test-circuit and some screens of the soundcard-result using > > SDRadio can be seen on: > > > > http://www.b-kainka.de/iqrx3.htm > > > > I have a lot of not and more successfull tries within different cards. > > Now I seem to be able to chosse the best one for my work. > > > > Wolfgang Hartmann > > Wolfgang, > > that page looks as it is contains very valuable information. It is a > pity I don't read German... I will try with the automatic translator > of Google, but sometimes the results are quite funny... > > 73 Alberto I2PHD >
