SDR# with DSD+ audio not working

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kb1ejw

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Sorry if this was discussed before, but I can't seem to get SDR# to play back audio using the DSD interface. I am trying to set up DMR decoding. I've been fooling with it for a few hours at least.
Let me start by saying I watched, and followed
How To Setup SDR # Sharp To Decode DMR Digitial Using DSD Plus And An RTL SDR Receiver on Windows 10

I noticed in the command line screen before, the output audio was never correct (I didn't think anyhow). i figured that out, and set the -o1 for my speakers, but still can't get anything out of it. The "source audio" box appears audio is flowing, as its moving quite rapidly.. but I can't seem to get audio back out of DSD+.
Currently, the Output audio of SDR# is set to CABLE Input. The DSD audio device is set to the same.

The audio, according the to CMD box is showing:
Audio input device #1 = "Cable Output"

Audio Device output #1 = 'Speakers (Realtek)"

both of which is what I want (I believe)..and the lines below show the same- Device #1 and device #1 for input and output...

If I stop DSD+ and change my audio in SDR# back to the realtek speakers, I hear the static/ audio.

I must be missing something here...?
This might be something- I have the same setup on 2 computers, and they are both giving me the same problem. I know I could use FMP that came with DSD+ but I'd like to do more with SDR# and possibly plugins. When I use FMP on the desktop, it works ok but still no audio. When I try on the laptop, which is what the screenshot is from, The last line in the CMD box says
USB_Open error -12
Can't open RTL SDR Device #1 and it closes.

But, SDR# still works....

Thanks for any help!
 

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kb1ejw

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You're filtering audio and you're tuned to 88.5 MHz? Doesn't sound like a spot where one would find DMR.
Regardless of any frequency I'm still not getting audio. The location I was testing this, I have no digital signals in any band. You mentioned a filter, could this be an issue? I see it now you mention it- never noticed it before, so many settings and all
 
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mtindor

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Regardless of any frequency I'm still not getting audio. The location I was testing this, I have no digital signals in any band. You mentioned a filter, could this be an issue? I see it now you mention it- never noticed it before, so many settings and all
Right. UNcheck "filter audio" in SDR# and set your bandwidth to something like 7900, and use NFM. Park on a knwon DMR frequency. When you see the activity in the Activity Window of DSDPlus, pay attenetion to wheather it says its encrypted or not. You might not be hearing DMR traffic because it might be encrypted. Attach a screenshot of the DSDPlus Event Log window when you see DMR calls coming in.
 

kb1ejw

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Right. UNcheck "filter audio" in SDR# and set your bandwidth to something like 7900, and use NFM. Park on a knwon DMR frequency. When you see the activity in the Activity Window of DSDPlus, pay attenetion to wheather it says its encrypted or not. You might not be hearing DMR traffic because it might be encrypted. Attach a screenshot of the DSDPlus Event Log window when you see DMR calls coming in.
OK, Perhaps I didn't understand the purpose of DMR & DSD... If it''s working properly, it will NOT let through audio, unless an appropriate signal is received and decoded? I was expecting it to act as an open squelch scanner where I would hear static or something (Which is why I had the freq set to 88.5 so I could hear static) I'm actually quite new to digital radio because it's not widely used in my area (at least not many stations of interest to me, however more public safety are coming online using it which is why i'm doing this project) Thanks for your help!
 

mtindor

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Use "dsdplus -h" to take a look at all of the switches available. When DSDPLus is running, on the Activity Log screen press ? to see what options are available in the app.

You can cycle the raw audio source monitoring mode -- which defaults to 0. other options are 4 / 3 / 2 / 1. So if you ever want to listen to an analog signal, or just hear what is being heard [raw] by DSDPlus, you can switch to one of the non-zero M values by pressing "m" to switch to that one. Then when you don't want to hear anything but decoded digital voice, just press "m" until it's set back to 0.

Mike
 

slicerwizard

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OK, Perhaps I didn't understand the purpose of DMR & DSD... If it''s working properly, it will NOT let through audio, unless an appropriate signal is received and decoded? I was expecting it to act as an open squelch scanner where I would hear static or something (Which is why I had the freq set to 88.5 so I could hear static)
DSD+ 1.101 doesn't work that way and open squelch between digital voice calls gets old real fast. And the video you linked doesn't show any static being passed in the gaps between voice calls...

Use "dsdplus -h" to take a look at all of the switches available. When DSDPLus is running, on the Activity Log screen press ? to see what options are available in the app.

You can cycle the raw audio source monitoring mode -- which defaults to 0. other options are 4 / 3 / 2 / 1. So if you ever want to listen to an analog signal, or just hear what is being heard [raw] by DSDPlus, you can switch to one of the non-zero M values by pressing "m" to switch to that one. Then when you don't want to hear anything but decoded digital voice, just press "m" until it's set back to 0.
Not an option in 1.101
 

kb1ejw

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DSD+ 1.101 doesn't work that way and open squelch between digital voice calls gets old real fast. And the video you linked doesn't show any static being passed in the gaps between voice calls...
OK.. then how does it work?? I DON'T want to listen to static, but I thought I would hear something to make sure audio is running through the hardware, software, soundcard,etc. I am new to SDR, and all other times I monitor , I hear traffic/ static. So, I was expecting to hear radio traffic using DSD+
Slicerwizard, if you want to reply with unhelpful comments, find other posts to degrade. Perhaps try to educate instead of insult. Go back to "slicing" meats (I'm pretty sure your username you wish to refer to data slicing, but you remind me of an angry Italian butcher)
 
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simpilo

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OK.. then how does it work?? I DON'T want to listen to static, but I thought I would hear something to make sure audio is running through the hardware, software, soundcard,etc. I am new to SDR, and all other times I monitor , I hear traffic/ static. So, I was expecting to hear radio traffic using DSD+
Slicerwizard, if you want to reply with unhelpful comments, find other posts to degrade. Perhaps try to educate instead of insult. Go back to "slicing" meats (I'm pretty sure your username you wish to refer to data slicing, but you remind me of an angry Italian butcher)
When I was new to it someone long time ago someone explained it in this manner:

The block diagram per se:
SDR# >>>Virtual Cables>>DSDPlus>>>speakers

A good virtual cable type software would be VB-Audio (donationware) or virtual cable (shareware)
In your windows mixer also make sure in Recording Devices you have the virtual cable set for default. Same for Playback devices BEFORE loading DSDPlus and SDR#
In SDR# make sure to set Audio output to your virtual cable...
All you should really need to do now is load up DSPlus.
Find a DMR frequency in your county using the database search here at RR.
Use that frequency in SDR#
In the DSDPlus event window you should at least see something like "DMR BS DCC:1" at the bottom. (BS= Base Station not the explicit lol!!)
In DSDPlus console (window with black background) you should see a bunch of repeating "messages" which means it's decoding properly.
I hope I helped.

After you familiarize with DSDPlus 1.01 and feel like you like it and want the newer versions of DSDPlus I recommend purchasing at least the $10 yearly Fastlane subscription for DSDPlus Fastlane. It features TCP mode which eliminates virtual cables but requires you to use FMP and DSDPlus together. FMP is the radio component. You can already do that now but not as feature rich as the Fastlane version nor as optimized as the DSDPlus Fastlane version.
 
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kb1ejw

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When I was new to it someone long time ago someone explained it in this manner:

The block diagram per se:
SDR# >>>Virtual Cables>>DSDPlus>>>speakers

A good virtual cable type software would be VB-Audio (donationware) or virtual cable (shareware)
In your windows mixer also make sure in Recording Devices you have the virtual cable set for default. Same for Playback devices BEFORE loading DSDPlus and SDR#
In SDR# make sure to set Audio output to your virtual cable...
All you should really need to do now is load up DSPlus.
Find a DMR frequency in your county using the database search here at RR.
Use that frequency in SDR#
In the DSDPlus event window you should at least see something like "DMR BS DCC:1" at the bottom. (BS= Base Station not the explicit lol!!)
In DSDPlus console (window with black background) you should see a bunch of repeating "messages" which means it's decoding properly.
I hope I helped.

After you familiarize with DSDPlus 1.01 and feel like you like it and want the newer versions of DSDPlus I recommend purchasing at least the $10 yearly Fastlane subscription for DSDPlus Fastlane. It features TCP mode which eliminates virtual cables but requires you to use FMP and DSDPlus together. FMP is the radio component. You can already do that now but not as feature rich as the Fastlane version nor as optimized as the DSDPlus Fastlane version.
Thanks, This does help. I thought the VR cable was before the DSD...I have both VB & audio cable.. My trouble is finding a DMR freq. .. where I am testing this, I have VERY poor reception, in a valley between 2 granite mountains essentially.. so I have to trek up to a higher location to try this all out. Thanks for everyone with your great info. It'll make it easier to understand what I'm seeing and what to change.
 
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simpilo

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Thanks, This does help. I thought the VR cable was before the DSD...I have both VB & audio cable.. My trouble is finding a DMR freq. .. where I am testing this, I have VERY poor reception, in a valley between 2 granite mountains essentially.. so I have to trek up to a higher location to try this all out. Thanks for everyone with your great info. It'll make it easier to understand what I'm seeing and what to change.
Your area has a few Con+ and 1 Cap+ system? Which one are you wanting?

I can say right now Cap+ is going to be unique to you because the Control Channel is really called a 'Rest' channel. It transmits in bursts of DMR data and its not continuous like other trunked systems. Cap+ Rest channel bursts are roughly split second spaced in 1.4 seconds. On the other hand, Con+ has a continuous transmission on it's control channel which is a control channel. I have the feeling you will need DSDPlus Fastlane to do Cap+ and Con+ type DMR trunking properly. I heard there is a SDR# plug in to do at least Cap+ but I am not real clear on it. I wouldn't try it anyhow. DSDPlus Fastlane is probably the best only option that can do it properly outside of a scanning radio with it built in.

Here is my video example I posted on YouTube for just an example how a Cap+ system works.
 
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kb1ejw

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Your area has a few Con+ and 1 Cap+ system? Which one are you wanting?

I can say right now Cap+ is going to be unique to you because the Control Channel is really called a 'Rest' channel. It transmits in bursts of DMR data and its not continuous like other trunked systems. Cap+ Rest channel bursts are roughly split second spaced in 1.4 seconds. On the other hand, Con+ has a continuous transmission on it's control channel which is a control channel. I have the feeling you will need DSDPlus Fastlane to do Cap+ and Con+ type DMR trunking properly. I heard there is a SDR# plug in to do at least Cap+ but I am not real clear on it. I wouldn't try it anyhow. DSDPlus Fastlane is probably the best only option that can do it properly outside of a scanning radio with it built in.

Here is my video example I posted on YouTube for just an example how a Cap+ system works.
Well, I don't know what Con+ and Cap+ is, so that's a disadvantage for what I'm looking for LOL
 

foxtail

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Sounds like your just not happy with any advice here....
Maybe try reading about radio systems in your area....maybe try another radio system other than DMR..
Read, read and when your done reading...go back and read it again...
 

kb1ejw

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Forgive me if I seem ungrateful, which is certainly not the case. I value all of the info everyone has given. My major setback right now, is I just can't start to test any time I wish, because of poor location and currently no outside antenna. I did a google search for Con+ and Cap+ and I didn't see anything in regards to radio communications, but I would think somewhere on this forum, perhaps in the wiki about how it all works, I just have to get a little time to find it. Free time is broken up between work and family. In my opinion, the best thing I have gained, to start with was how SDR#, DSD+ and VB cable route the sound, where I thought I should have been hearing something, not to mention settings and frequencies that were all wrong anyhow
 
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simpilo

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Let me see if a visual aid will help you figure out if you are seeing a CAP+ DMR trunked radio system. In the image is HDSDR receiving a CAP+ Rest Channel "blips" If you see the same thing you can maybe receive that system. My example is a weak CAP+ DMR Rest channel yours might be similar or stronger (brighter colors). Scan the known frequencies. All frequencies in a Cap+ system serve as both Rest and DMR voice. Rest channel is one of any of them and the Rest channel always switches frequencies ascending the list of LSN's. Each frequency has 2 time slices so if your system has 5 frequencies you have 10 LSN's. An LSN can be thought of as a "channel".

I also want to note that with FMP24 CC and CC DSDPlus it can pick out the rest channel and decode it at low signal levels as long as they "spike" about 5-10 dbm off the noise floor. However, DMR Voice transmissions, in my experience, need a stronger level. I don't know the science behind it why it is that way but that's how it goes.
 

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