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SDRPlay Performance

Posted: Wed Sep 28, 2016 10:45 pm
by Bill
I'm new to this board and to SDRPlay and I'm having trouble getting my SDRPlay to work without choppy audio. My system is Windows Vista 32 bit, 4 GB of ram and a 2.40 GHz processor. Is this system too slow to run SDRPlay? I have read that you need to use a USB 3.0 port but the SDRPlay doesn't have a USB 3.0 connector as far as I can tell. As I have read, a USB 3.0 port will need a USB 3.0 cable to perform up to spec. My FDC (Fun Cube) runs just fine on this system but of course we aren't talking about the same bandwidth and I'm led to believe that that could be the issue with the SDRPlay.
Is it time to upgrade? :) Thank you in advance.
Bill

Re: SDRPlay Performance

Posted: Wed Sep 28, 2016 11:20 pm
by sdrplay
Hello Bill,

The RSP is a USB 2.0 device not USB 3.0 - we find that some USB 3.0 chipset backwards compatibility to USB 2.0 is pretty poor so we always recommend using USB 2.0 ports wherever possible.

I'm not sure what SDR application software you are using, but a first step would be to reduce the bandwidth and sample rate you are using. I would recommend starting with 1.536MHz IF bandwidth and a sample rate of 2MHz.

Best regards,

SDRplay Support

Re: SDRPlay Performance

Posted: Thu Sep 29, 2016 1:00 am
by Bill
Thank you for the quick reply. I neglected to say what software I was using alright. ;) I had tried SDRUNO and SDRConsole with the same results. I thought that I had selected a narrower band width but I will double check that. I realize that the SDRPlay is a USB 2.0 device that is why I was confused by the messages that I had read that were to the contrary and knew that a USB 3.0 cable wouldn't work anyway. I will give it another try and check back. :) If I need to upgrade then so be it. :D

Bill

Re: SDRPlay Performance

Posted: Fri Sep 30, 2016 4:59 am
by Bill
Well, I have tried setting the band width as low as it can be set and the problem persists. At times the choppy audio is almost gone but never completely gone.
Bill

Re: SDRPlay Performance

Posted: Fri Sep 30, 2016 6:43 pm
by Misterj
Bill, are you sure you are using a USB 2.0 port? How many cores does your CPU have? Please open the Task Manager and tell us what CPU usage is for SDRuno. Are any other applications running and what is the total CPU and memory usage. I would think your LT has sufficient power to run SDRPlay. Can you try the SDRPlay on another computer (SDRuno is the ONLY SW you will need)? Good luck and enjoy, John.

Re: SDRPlay Performance

Posted: Fri Sep 30, 2016 10:53 pm
by WhoaNellie
Try running HDSDR for your software with the SDRPlay. It uses less CPU resources. If you have problems with it too, then you may need a more powerful computer but I don't really think that's the problem. HDSDR will show the CPU % used in running it, as well as system % utilization overall (note that SDRUno also shows this in the Main window). You can get HDSDR here:

http://www.hdsdr.de/

Re: SDRPlay Performance

Posted: Sat Oct 01, 2016 12:13 am
by Misterj
Bill, I just ran a test on my old, tired LT (AMD A6, 4 core 1.4 GHz, 4GB). SDRuno ran OK but certainly not like my DT. Please try the following settings and let us know your results. Of course, set the frequency to an FM station in your locale. I also tried my AirSpy and found that it did just fine.
Image
Mono sounded better on some stations and some stations just sounded better. Enjoy, John.

Re: SDRPlay Performance

Posted: Sat Oct 01, 2016 2:40 pm
by Bill
I appreciate all of the help. Checking the CPU usage was revealing. There is a computer problem. The CPU usage goes to 100% shortly after starting the computer. The processor is a single core and the USB port is definitely USB 2.0. I have been doing searches and finding that I'm not the only one that has had or is having this problem. I'm still looking for the source of the problem. Task manager shows that the running applications are using very little of the resources so it isn't any help in spotting the problem. Most programs seem to run OK, amazingly. I will try the suggested settings just to see what happens but I'm probably going to have to do a reinstall. I think that some application the I have downloaded recently caused this issue. A full virus scan didn't come up with anything either.
Thanks again and I will check back in to let you know what, if anything, that I find. A new computer would hurt either. :)

Bill

Re: SDRPlay Performance

Posted: Sat Oct 01, 2016 9:38 pm
by Bill
OK, after many uninstalls and internet searches, not to mention reboots, my computer will run the SDRPlay. The real culprit apparently was Windows update set to automatic. Removing other software and so on, would have an effect on the CPU usage at the initial start up. In other words, it took a little longer for the CPU usage to climb to 100% and stay there. Once I disabled the auto update checking, the CPU usage would vary depending on what software was running, mostly Firefox. At that point I reinstalled SDRuno and using the above settings the CPU usage would average about 70% (The processor not being any kind of power house. :) ). This was on a local broadcast FM stereo station. Tuning in NOAA on VHF would drop the CPU usage to around 60%. If I opened a new tab or refreshed a tab in Firefox the usage would jump to 100%. This was with SDRuno also running and SDRPlay would continue to operate fine at this point. The CPU usage would vary when trying out the HAM bands but was always usable. No more choppy audio. :P
At this point all would appear to be well, although I'm impressed enough with this computer to start shopping for a new one. :D Thank you yet again.

Bill

Re: SDRPlay Performance

Posted: Sun Oct 02, 2016 12:01 pm
by dsalomon
If you're running at a constant level of 60%-70%, you will get spikes to 100% from just about anything else you do, especially Firefox, which is known to be a resource pig at times. You should run this on something that stays level at no more than 20% when running the RSP. Also, it you're at 60%-70% with a small bandwidth and sample rate, you still won't be able to run at a larger ample rate and/or bandwidth. o, bottom line is that you need to do something or you'll continue to struggle with it and have problems and sound breakups. One thing you might also look at is the USB chipsets on your PC. Some work much better than others with data streaming. You might be able to get better results with an addon USB card with a Reneas chipset. Those are known to work well with streaming large volumes of data. I had the same problem on a high end system (processor with 12 cores, 32GB memory) and couldn't solve it until I added a USB3 card with a Renesas chipset and all my problems went away. I bought USB3 because I have another SDR that requires USB3. There are lots of USB2 cards with that chiipset. One other thing to note when buying an addon USB card is the number of processors per port. The less expensive ones will run up to 4 USB ports on a single processor on the card. The better (and more expensive ones) will run 2 ports per processor or even a single processor per port. That last one is the ideal for performance where each USB port has maximum available bandwidth. You won't find those cards for $5 - they'll cost significantly more. However, if you're building a system to maximize performance for a bandwidth hog (i.e. ANY SDR), it's something to consider to help ensure you don't have bandwidth related issues.

Good Luck - David