Re: [Discuss-gnuradio] ADC Specs

[Matt Ettus]

Brian Padalino wrote:
> On Mon, Dec 15, 2008 at 4:41 PM, Aadil Volkwin <address@hidden> wrote:
>   
> > "The full range on the ADCs is 2V peak to peak, and the input is 50 ohms
> > differential. This is equates to 40mW, or 16dBm."
> >     

I am not sure where that sentence came from, but it is incorrect.  The 
correct statement would be:


"The full-scale range of the ADCs is 2V peak to peak.  The BasicRX and 
LFRX have unity voltage gain and an input impedance of 50 ohms.  Thus, 
their full-scale input is 2Vpp, or 10dBm."


2Vpp is equal to 1 Volt peak, or .707 Vrms.  At 50 ohms, this comes to 
10 mW or 10dBm.  Also, while the ADC has a nominally 200 ohm input 
impedance, the BasicRX and LFRX terminate in 50 ohms. 


Matt