Re: [Discuss-gnuradio] LW/AM/SW radio very cheap in laptop?

[Firas Abbas]

Hi,

--- On Thu, 4/2/09, John Gilmore <address@hidden> wrote:

> There's another chance to get kids into radio...
> 
> If a high volume kids' laptop had stereo "HD audio" ports available
> (24-bit 192 kHz converters, 95 db input and 100 db output), how cheap
> and small a circuit could you build onto that motherboard to provide
> useful LW/AM radio reception?  
> 
>     John


Here is my 2 cents:

1) AM signals known to be strong, RF Gain may not be required.

2) Undersampling can be used to downconvert/digitize AM signals.

3) RF Tunning is the problem. We have to think for away to use the voltage from 
one of the audio output ports to control a bandpass filter center frequency 
(voltage controlled filter).

4) Software demodulation.

Best Regards,


Firas