If the tuner output impedance is known, you could use a balun transformer of the right type to convert the signal, and get total galvanic isolation as an extra.
Also, you need a good lowpass filter because the audio cards sample at 44100 or 48000 Hz and the lowest tuner output bandwidth is surely > 1 MHz.


2013/6/12 Leif Asbrink <leif@sm5bsz.com>
Hello Zilvinas,

This should work very well:-)

The IQ signals are balanced and the proper
procedure would be to use a differential
amplifier to convert the voltage difference
between I+ and I- to a voltage difference between
the ground reference and the input of the soundcard.

You can try just putting a wire from I+ to
the soundcard input. A capacitor in series
might be needed. The simple solution might
add hum and noise near the center frequency.
Such problems are cured with the differential
amplifier.

Then, do the same for Q:-)

Regards

Leif / SM5BSZ


> Hi all !
>
> Please excuse me if this is a bit off topic.
>
> Is there any sense to tap the IQ signals from e4k or r820t to the
> internal or external soundcards.
> Is it possible at all (with r820t particularly) ?
>
> (It could seem like reinventing funcube dongle, bet the
> performance/price would be still right)
>
> Best regards,
>
> Zilvinas
>




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