Possible bug: perfect audio, jittery waterfall

[KD2TBO]

Hello! SDR-Console is working *splendidly* for me, with one small exception: the waterfall display is a little bit jittery no matter what I try. First, some details:

Software Version: 2022-09-18_1224.exe
SDR: SDRPlay RSP1A
Machine: old-ish i7-6700T 2.80GHz with Intel HD Graphics 530
OS: Windows 10

What exactly do I mean by "jitter"? The waterfall seems to be constantly jumping forward (and sometimes backwards) by a pixel or two as it falls. It's very subtle, appearing more as a "flicker" or "vibration" rather than big noticeable gaps or jumps. It's worth noting that my audio playback is perfect, no issues there. It's just this weird jitter on the waterfall, where instead of moving smoothly downward at the selected speed, it moves with a flicker.

Here's a list of things I've tried, with the jitter present on all of them:
- Various displays, including a 1080p monitor and 4K TV at 60Hz
- All the different FFT algorithms
- All the different FFT resolution settings
- A bunch of different waterfall speeds, from 10Hz to 100Hz
- Checking the in-app performance monitor, which is reading around 10% for the UI and close to 0% for all the other sub-processes
- Different bandwidths for my RSP1A, both 2MHz and 10MHz
- Setting the app to Realtime priority in the Task Manager

Has anyone else encountered this? I've run out of things to try!

[jdow]

Perhaps the frequencies you are monitoring have signals that are not perfectly stable? It might be changing a few Hz which could cause display changes even when the display is something like 1.111 kHz per pixel.

{^_^}

[KD2TBO]

That's really interesting! I'm testing with FM radio (93.9 MHz here in NYC), but is there an ultra-stable reference signal you'd recommend?

I might be missing something here, but would the signal stability affect the vertical speed/behavior of the waterfall? The entire display is showing this up-and-down vibration, and I was under the impression that it should fall at a consistent rate no matter what signals are present. There's no side-to-side jitter, just up-and-down, very mysterious.

[RadioSDR1]

@KD2TBO

Hmmmmm. Not that I am the most expert user but I have used SDR Console enough with an RSP1A to have seen it do some weird and obscure things but never a waterfall issue of the type you describe. Given all you've tried and the fact that you report SDR Console works fine otherwise makes me wonder if you have some issue with video on your computer. If so, perhaps the waterfall from another SDR application might give similar results. Perhaps you could try HDSDR or SDRUno (if you haven't already). If the waterfall with those programs works without a problem, then something deeper more obscure is going on. But if you have a problem there too, then make sure all Intel chipset and video drivers are updated.

Another interesting test might be to change the video driver to the Microsoft generic video driver. It'll be low resolution but results of that test might point to something. Also, not sure if SDR Console will run in Windows Safe Mode but if it does, might try that too. Perhaps something is running in normal mode making the waterfall mad. And if you happen to have another video card laying around that will fit in the PC, try that too.

[Max]

Hello! SDR-Console is working *splendidly* for me, with one small exception: the waterfall display is a little bit jittery no matter what I try. First, some details:

Software Version: 2022-09-18_1224.exe
SDR: SDRPlay RSP1A
Machine: old-ish i7-6700T 2.80GHz with Intel HD Graphics 530
OS: Windows 10

I have until very recently run SDRC on an older processor than yours (i7-2700 circa 2011), originally with HD graphics. I never remember seeing what you describe. This has to be a graphics issue.

Two things you could try. Firstly, if it's not already on, turn on Hardware Acceleration in Windows 10. Or if it is already on, turn it off.

https://www.majorgeeks.com/content/page ... ndows.html

Secondly, I cannot recommend highly enough how much better the performance of your PC will be if you upgrade to a discrete graphics card. For a relatively inexpensive solution, and a very well regarded one, I can highly recommend any of the Nvidia GTX 1650 Super variants. Very important to note the "Super" at the end. Oddly, it's a very different variant to the stock 1650.

They must by now be available on eBay for low prices. Try that and you will not be disappointed. Also my guess is that with the regular onboard HD graphics, you cannot make a screen video recording within SDRC, but with the 1650 Super you will be able to, and I'd wager it will almost certainly vastly improve your PC performance not only on SDRC but on many other programs as well.

Good luck.

Max

[KD2TBO]

Hey everyone - thanks for all the helpful suggestions! I tried this again on an entirely different computer with a 1080Ti graphics card, and saw the same stutter. So perhaps this is just... the way the waterfall is supposed to look? I'm a bit baffled but seems like there's not much I can do.