[Skimmertalk] Compact Computer Boards with SDR-IQ for CW Skimmer

[Pete Smith]

At 04:38 AM 12/4/2008, Jeff Maass wrote:

>I'm interested in packaging SDR-IQs with compact Single Board Computers 
>(SBC) and small
>drives to make easily-transported skimmer nodes feeding Writelog via telnet.
>
>Has anyone successfully used a 4x6-inch (or so) SBC with CW Skimmer in 
>this way yet?
>
>What is the minimum "CPU horsepower" that can be considered practical for 
>decoding a band
>during contest operation?
>
>For those running multiple SDR-IQ with Skimmer, are they each equipped 
>with their own
>high-horsepower PC, or can a single PC be configured to handle multiple 
>SDR-IQ boxes with
>CW Skimmer instance or instances?

I'll let others who know better respond to the multiple-instances 
question.  I'm not clear on the fine points of SBC design, but this much I 
can tell you.  I run a 2.66 GHz Celeron with 2 gig of RAM, and have both 
Skimmer and N1MM Logger running. During a busy contest, I have to limit the 
number of decoders that Skimmer spawns to 250 or 300, to avoid getting in 
the way of MM, particularly when doing SO2R and switching the transmit 
focus from one radio to the other.  My computer reaches 100 percent CPU 
utilization at about 400 decoders.

With a dual-core Xeon, it would be interesting to associate Skimmer with 
one core and put everything else on the other one (using the Affinity 
setting).  Feeding the SDR-IQ directly to Skimmer via USB, I have noticed 
no additional CPU demand.

73, Pete N4ZR