[Premium-Rx] RFSpace SDR-14 digital receiver

[Terry O'Laughlin]

My friend has a very well equipped test bench including esoteric stuff like 
a noise figure meter.  He tested the SDR-14 and found it to be 
excellent.  Sensitivity is superb, well under 1 uV across the range.  The 
shape factors of the "IF filters" are beautiful.  The noise figure rose to 
11 dB in the 30 MHz range, but at HF frequencies that is decent and 
comparable to most conventional receivers.  The box is very quiet emitting 
almost no birdies.  We didn't discuss intermod or overload.  The box 
digitizes right after a single preamp stage, so the ADC is the only 
significant non-linear device in the RF chain.  I'd be curious to see IP3 
and other performance test data.

The DSP based demodulation is a CPU killer.  He runs a Pentium 2.8 GHz 
machine and it is running flat out when demodulating.  A Pentium 1.7 GHz 
machine runs the waterfall and SDU just fine but stumbled regularly on 
demodulation finctions.  Hard drive space is also a factor as the SDR-14 in 
record mode churns out data like a fire hydrant running wide open.

It is so different from ordinary radios I found it hard to 
compare.  Knowing that it is only the first device in a design trend and it 
performs so well is amazing and begs the question, what is next?

Terry O'



At 12:29 AM 6/25/2004, you wrote:
>Keep in mind that the SDR-14 is more of a lab instrument, rather than
>strictly a receiver. It will be lacking in certain performance specs that we
>take for granted in a premium or "serious" consumer-grade receiver, for that
>matter. From the rfspace.com web site: