[Skimmertalk] red pitaya, for real?

[kazeringue at aol.com]

Alright, thanks folks.

The Red Pitaya looks pretty interesting just for its capabilities as a 
test device, which should improve with software over time.  That would 
be a lot of help with testing on the band pass filter projects. I 
foresee another project..... a bank of W3LPL design rx bandpass filters 
as a preselector between the antenna and preamp going into a Red Pitaya 
SDR, and use the Red Pitaya to tune them.  [50kw 680 AM broadcast 
antenna is 1.2 miles from my house]

Being able to run RP as a skimmer server would be a big bonus.

Idle speculation, the high impedance on the inputs is there for its use 
as a scope/test instrument.  Bypassing them per K1TTT jumper fix might 
be easier than trying to match them for SDR use.  Figuring out a good 
match for the amp block following JP5 might be worth the time tinkering.

Interested to hear more from Dai on the S9-C also.  More options is good.

So, one last question.  What sort of CPU is sufficient for a Red Pitaya 
based SDR?  What sort of CPU's have been used and what sort of CPU % 
usage is the skimmer server drawing?

I have been running up to five softrocks on a single Dell core 2 quad 
box(2 physical threads, 2 virtual threads) under windows 8.1.  With all 
five running on a contest weekend, the CPU is over 50%, usually closer 
to 70%.  The tough part of that kludged skimmer station was finding five 
different sound devices that could coexist. (Four plus the onboard 
sound.)  Since the 15m softrock kludge generates more bad mirror image 
spots than the others, I generally just run four skimmers, 160/80/40/20.

73 de w4kaz