(long post with a lot of info, so be warned...)
Try these settings for SDR# and see what happens - they don't have to be permanent, just try them and go from there (and of course use the two tips above about unfiltered audio and the Correct IQ checkboxes):
Under Configure (the button to configure sample rate/ppm/etc):
- 1024 MSPS
- set your ppm to as accurate as possible after a 5-10 minute period of warmup
- uncheck all 3 boxes, set the RF Gain to 28 dB
Main window:
- NFM
- Filter type is typically irrelevant since we're not filtering the audio signal being fed to DSD+
- Filter order set to 10
- Squelch as required (I set mine at 60 almost always and that's that)
- Correct IQ checked
- AF Gain set to roughly the next to last notch on the right side of the slider
As far as DSD+, if you intend to decode DMR/MOTOTRBO specifically then you should always use:
-fr
at the bare minimum so it ensures DSD+ is only going to focus on detecting and decoding DMR/MOTOTRBO traffic and ignoring anything else. Obviously you're using Auto (defaults) for detection as shown by the info line on the command prompt windows you pictured.
While I'm not going to tell you what you're looking at is all wrong or whatever, I will say this: if you alter the settings for the spectrum display and the waterfall so you're getting actually useful information instead of a "wall of noise" as you currently appear to be doing, I promise you it'll make things easier. Try these tips if you wish, or not, it's up to you:
- you want to adjust the FFT spectrum so that it's only going to display the signal(s) you actually care to look for or listen to, that means having all the noise under the noise floor is pretty much useless to just have there being displayed. I can't tell what your apparent noise floor is from the pictures you've shared because you've zoomed in so much - zoom all the way out and then look at where the spectrum shows your average noise floor is. On the image I've attached below the average noise floor is about -65dB which is typical for most RTL sticks, it's just a side-effect of them being "cheap USB TV tuners" and not having such great noise suppression. The point being that - just for the image I took - I adjusted the range of my FFT display so it "cuts off" at -70dB since anything below that is for most all intents and purposes going to be drowned out by that noise floor.
You've got your FFT display range set for -130dB which means you're going to be forcing the FFT display to show you "nothin' but noise" below your average noise floor. The images show a roughly -30dB "floor" across the visible spectrum which means one of two things to me: 1) you've got the RTL AGC on + you've got the RF Gain set to at least 30 dB or higher, or 2) you've got the Tuner AGC on which will basically max it out across the spectrum and it's a very bad thing.
So try this: set the Zoom to the lowest level (maximum Zoom out, or slide it to the bottom), and look at the spectrum. If you're using a typical RTL stick, it'll have an average noise floor around -50 to -65dB or so, somewhere in there is what these sticks provide and there's not much that can be done to lower it (they're just noisy, period). Once you can see what your current hardware's average noise floor is, adjust your FFT display Range slider so it shows the level just below the average - as you can see in the example image below I've got mine set for -70dB at the moment, that's the bottom of the range. I normally adjust it to -60, sometimes -50 actually and by doing so what I am getting are the signals that matter. If I want to "see" more activity I don't have to adjust the Range again, I just increase the Contrast of the waterfall and the signals will "pop out" visually if they're there.
Uncheck all three of the boxes for Offset Tuning, RTL AGC, and Tuner AGC (meaning those options are
off - I don't even know what Offset Tuning is used for but I figure it's there for some reason, uncheck the box anyway for the time being). Set the slider to 30dB for testing purposes and that's your only signal gain for now and see what you get. DMR/MOTOTRBO signals are typically easy to spot on the waterfall but... that's the next tip. If you're overloading the front end or saturating the receiver by maxing out the gain with those gain settings (checkboxes checked) then that's another reason the DMR/MOTOTRBO will be affected and not decode properly.
- your waterfall is set to basically set to "something" that I can't see because the command prompt window is blocking it. As you can see from my example below, I keep mine at about the halfway point - I am NOT saying my way is the best way, so please understand this, I'm simply saying that if you're using this method of communications monitoring, it really helps to be able to "see" the signals apart from all the noise. You can adjust the sliders on the right side to kick out the Zoom and see what's going on as well as reducing the Contrast so you can discern the signals. In my example image the DMR/MOTOTRBO signal is right there, absolutely impossible to miss. If I crank the Contrast up I can still see it of course but it gets drowned out by a "wall of visual noise" for the most part.
You can also spot little "blips" of transmissions all across the waterfall - those are data bursts from water heaters and the like (the longer bluish ones), the thin reddish orange one just to the left of the DMR/MOTOTRBO signal I'm monitoring/decoding is an NXDN control channel, and the very tiny bluish and orange ones are squelch breaks from LTR trunking systems here in my area.
The visual spectrum and the waterfall are really what make this so much different from "the good old days" and a big reason for the appeal and quick adoption of SDR using these "cheap USB TV tuners" - it seems logical that if you adjust things so you can actually see what's going on in the spectrum, as well as being able to discern signal/transmission types visually by how they look on the waterfall is a big big plus to things.
Seems like most people don't grasp they can adjust things so they get actually useful visual info they can interpret nearly instantly instead of having to try and "decode" what they're seeing. Makes sense to me, hope that makes sense to you, dubs0980, or anyone else.
EDIT:
One last tip: for the VB-Cable Audio settings, you do NOT want to pass the VB-Cable Audio to your speakers, that means you'd be hearing the actual digital data stream
on top of hearing what DSD+ is providing you as decoded audio. Uncheck that box in the VB-Audio Cable options for "Listen to this device" - it's unnecessary and just means you get that annoying data stream mixed in with the decoded audio (when it works, of course).
One last last tip: Check the frequency or frequencies to verify what you're getting is a DMR/MOTOTRBO signal. If you had a strong signal, even with that apparently over-saturation in the image below (a wall of -30dB signal strength across the spectrum even as zoomed) it would show a nice peak above the rest, but I don't see a peak, at least not like the one(s) in my example image - there are two DMR/ MOTOTRBO transmissions in mine, one to the far left and one near the middle that I'm tuned to, both a very very easily spotted visually.
Based on those images above, and the spectrum (even with the -30dB signal blasting across the spectrum)
and coupled with the over-contrasted waterfall, I don't actually see a signal there at the frequency you're tuned to - there's nothing there but noise. The closest signal is a remnant over at 463.725 that's already passed down the waterfall.
