Hi,
I see comments on STEMlab's Red Pitaya scattered about the web many of which express frustrations in trying to get the RP to do what they want it to in a straightforward way. I thought I'd share my experiences.
These are not for serious applications. I wasted $800+ on two of these things based on the claims that the RP is for engineers to develop new instruments. Well, these claims have proven to be less than convincing. The 'scope and spectrum analyzer apps are terrible. In the latter case, you can't even average the spectrum or zoom in.
I needed three synchronized RF outputs. STEMlab claim RPs can be daisy-chained and synchronized. Yes, they can in principle but not out-the-box. To come even close, I would have had to use a 3rd party SDK, learn Linux, learn Vivado, learn VHDL and learn FPGA design - just to sync a clock. I tried. Requests to add this to the 'ecosystem' have gone unheeded. Apart from one very talented and knowledgeable gentlemen, STEMlab ignore the users' forum. I've wasted more than three months trying to work around this is and this isn't a hobby for me. Delays cost me money. I also need to be able to capture two analog signals (a few kHz). Well, the way capture has been implemented is inexplicable. 16K sample buffer with only about 7 selectable sampling rates ranging from 1.9kHz to 125MHz. There is no means of continuous capture. If I want to capture 60sec of signal I have to capture exact multiples of 8.5sec with gaps between. Now, I were a wizard electronics engineer, I could completely redesign the FPGA to address this but as an out-of-the-box item, it fails to meet its obvious potential. The hardware itself is great - the support and tools needed to make use of it are woefully lacking. In the end, I bought an MCC DAQ for $400 and a 4-channel RF DDS based on the AD9959 chip for $99. So, at least I learned something from my $800+ spend. And I ended up learning Python - which is awesome. BTW - do NOT buy directly from STEMlab - they still owe me for charging me for a unit I didn't buy. Use a distributor such as Mouser. And do your homework (read forums etc.) to make sure this thing will do what you want. It works for some but not for me with my modest requirements.
John.