SDRplay Community Forum

Hey guys,
My name is Calvin I’m a newbie here, I recently purchased a sdr play 2 pro and I’ve ran it with a windows laptop with sdr uno and it worked very well.
I have set it up now with a raspberry pi 3, with a fan and hesrsinks on the pi, running cubic sdr software.

The problem I’m having is it seems to be very laggy, the waterfall is laggy and even trying to select a station hovering the mouse is very jumpy. The Pi’s cpu temp is stable at 49.5 degrees Celsius. The only thing I’ve noticed and I don’t know if it’s normal as I couldn’t see it in the sdr play getting started video is the cpu usage is way up at 80-87%? I don’t know if this is normal or do I need to change something?(I’m pretty new to raspberry pi also)
I have ran gqrx software with another sdr I have here and it runs fine, no lag at all, would it be possible to even run the pi with gqrx? Hopefully some of yee guys can help me

Kind regards
Calvin

Hi Calvin,

From time to time I use CubicSDR on an iMac and it consumes between 85% and 120% processor according to Apple's Activity Monitor app which really surprised me. Being a cross platform app it probably uses it's own maths libraries and does not take advantage of any hardware assistance, or something like that.

Others say similar things, eg from https://www.scivision.co/cubicsdr-rtlsdr-linux/

CubicSDR is targeted for desktops and laptops–the CubicSDR GUI is beautiful, but takes more resources than earlier SDR GUIs.

and

The Raspberry Pi 3 can run CubicSDR–barely and with some hacking.

Unfortunately it sounds like your situation is normal for your Pi.

It's a pity because it's a really nice app in it's own way. Congrats on your SDRPlay purchase BTW, I love mine.

Regards,

Phil

Does the setting "reduce CPU usage" works?

Does the setting "reduce CPU usage" works?

Yes it does. Sorry for the delay, been away.

Did some quick tests at different sample rates, these are approximate because they vary depending on a range of factors but they are indicative.

500KHz ... 45% normal, 34% reduced CPU usage
2.048MHz ... 72% normal, 58% reduced
6MHz ... 107% normal varying up to 170% with band activity, 88% reduced

HTH, Phil

Hi Phil,
Thank you for your reply, I tried everything with the cubic sdr software to try get it to run smooth and reduce the cpu usage like reducing the sample rate, clicking the reduce cpu usage in settings, Mede hardly any difference, what is confusing me is how smooth it seems to run on the sdr play videos on YouTube.
Maybe I’m missing something? Love the sdr play 2 pro btw, works well with sdr uno on windows, I must try hd sdr with it yet