Update: See out new tutorial for trunked radio tracking, including digital voice trunked tracking.

The RTL-SDR software defined radio combined with SDRSharp, and a program called “digital speech decoder” (DSD) can be used as a radio scanner to easily and cheaply listen to unencrypted digital radio voice conversations.

Digital radio voice communications are becoming more commonly used in the radio spectrum. This is due to the various improvements offered over traditional analogue voice radio systems. Unfortunately for radio scanner hobbyists, digital radio is difficult to receive, as special radio scanners which can be expensive are required to decode the digital signal. Additionally, digital radio systems can be encrypted making it impossible for communications to be decoded by a hobbyist. However, most users of digital radio do not bother to encrypt their systems as it can introduce lag and extra battery drain in portable radios.

The most common digital speech codec is APCO P25, which DSD is able to decode. DSD is also capable of decoding other common digital codecs such as DMR/MOTOTRBO and ProVoice which no hardware scanner is currently capable of.

Super cheap software radios such as the RTL-SDR can be used to decode these digital voice communication signals instead of expensive radio scanners. While this tutorial is aimed at the RTL-SDR, other software radios such as the Funcube dongle, HackRF and BladeRF will also work. Hardware radios with discriminator taps may also work.

Examples of DSD Decoding Digital Voice with RTL-SDR as a Radio Scanner

YouTube user Geoff Wolf shows a video where he uses RTL-SDR as a police scanner to listen to public safety P25 digital radio using DSD, SDRSharp and virtual audio cable.

YouTube user Superphish uses RTL-SDR as a radio scanner to decode MOTOTRBO digital voice of a taxi company, using DSD, SDRSharp and virtual audio cable.

Tutorial – Decoding Digital Voice using SDRSharp, DSD and RTL-SDR (For Windows)

It is assumed you have an RTL-SDR dongle set up and working with SDRSharp. If not, see the buy RTL-SDR, and quickstart pages first before attempting this tutorial.

First, you will need to download the lastest DSD 1.6 version and extract the zip file or place the exe into a folder. Download the latest “Windows Port with P25/DMR Filter”.

Update 25 Feb 2014: Note that there is also the still in development DSD 1.7 available which can also decode D-STAR voice. DSD 1.7 needs to be manually compiled first. These links can help you to compile it for Windows and Linux. There is also DSD+ now available which has much improved P25 and DMR decoding, especially for weak signals. DSD+ download and instructions can be found here. With DSD+ the installation of Cygwin shown in this tutorial can be ignored, but pay attention to the steps needed to download lame_enc.dll on the above link.

Next, if you don’t have Cygwin installed, you will need to go to www.cygwin.com. Download and install the 32-bit version of Cygwin. Even if you have a 64-bit PC, you should use the 32-bit version of Cygwin as DSD is a 32-bit program. You can use the default install options, but make sure you record what “Root Directory” your Cygwin is being installed to. I just install to “c:\cygwin”.

Once installed, navigate to the root directory folder where Cygwin was installed to. Open up the “bin” folder, and find the file “cygwin1.dll”.

Copy and paste this file into the DSD folder.

You will also need an audio piping utility such as virtual audio cable. (The trial version of virtual audio cable may work, however a watermark sound is played periodically which could cause a bad decode). You can also use the free VB-Cable as a virtual audio cable alternative.  Also ensure virtual audio cable or VB-cable is set as the default recording audio device in windows sound properties as DSD will use the default sound device.

The sampling rate of your audio piping method must be set to 48000 samples/sec. To set this in Windows, right click your device in the Windows sound recording tab, go to properties and under the advanced tab, set the sample rate to 48000Hz. Do the same to the same device under the Playback tab as well.

Also, in your SDRSharp folder, open SDRSharp.exe.Config in a text editor such as Notepad, and ensure the key minOutputSampleRate has a value of 48000 such that the line reads as <add key=”minOutputSampleRate” value=”48000″ />.

If you are unfamiliar with what a digital voice signal may look like, two waterfall examples are shown below, with audio examples.

P25 (LEFT)

DMR/MOTOTRBO (RIGHT) 

Now to decode the digital voice signals follow these instructions.

1. Open SDRSharp and set the audio output to virtual audio cable or VB-cable.

2. Set the receive mode to NFM, with a bandwidth of about 12.5KHz.

3. Tune to a digital voice signal frequency. You will need to Google for these frequencies by your location. The radioreference databases may be a good place to start looking for these frequencies. Most digital voice frequencies will be around 850 – 900 MHz.

4. Open a command prompt from Start->All Programs->Accessories->Command Prompt, and navigate to the folder where DSD is located. For those who are not familiar with the command prompt, use the “cd” command to change directories within command prompt. For example, if your DSD folder is located in c:\Radio\DSD, you would type in command prompt “cd c:\Radio\DSD”.

5. Type in “dir” to show a list of files in the current directory, and look for the name of the DSD .exe file. Now type into the command prompt the file name of the DSD .exe file, which at the time of writing this article is “dsd160″, and then press enter to start decoding.

At this point, text should be scrolling through the command prompt window when a digital signal is broadcasting. Whenever someone speaks into the radio you should see the words “voice” in the window, and hear voice.

If the word voice is constantly showing and a garbled sound is playing, you may be listening to an inverted DMR/MOTOTRBO signal. Try typing “dsd160 -xr” into the command prompt at step 5 instead. More DSD options for other digital signals can be found by looking at the DSD help screen by typing in “dsd160 -h”.

To get good decodes (for most soundcards), the volume settings in SDRSharp and Windows should be played with until “inlvl” reads at approximately 30% for best performance. Note that all soundcards are different, and DSD may get better performance at a different percentage on your computer.

To stop DSD, simply press “ctrl + c” at the command prompt while it is running.

Some Tips

• If you don’t know what P25, MOTOTRBO, ProVoice or any digital voice signals sound like, this page has some more example audio files.
• You can simply manually scan through various signals, and see if DSD starts scrolling text to see if a signal is supported. DSD will start attempting to decode immediately. Note however that DSD will also scroll text on trunking channels, but will not be able to decode them. See the next section for information on decoding trunking channels.
• A strong signal is required for DSD to decode audio well. Ensure you are using a good antenna and have set the RTL-SDR gain correctly.
• DSD will listen to the default windows sound recording device. Make sure virtual audio cable or VB-cable is set as the default device. No text will be scrolling within DSD if the wrong audio device is used.
• Stereo mix can be used, but you will be hearing both the digital signal as well as the decoded voice at the same time. Also, the decoded voice audio will be pumped back into DSD causing a detrimental feedback loop.
• DSD is software in development and may not perform as well as a commercial digital radio.

More Advanced Digital Radio Scanning

As digital voice uses a trunking system, unitrunker can be run along with DSD to follow conversations across channels. Suprisingly, only one RTL-SDR dongle is required. This allows RTL-SDR to work as a proper radio scanner which can follow conversations across frequencies.

A good write up of how this can be done is presented here, with example video shown by YouTube user jcims.

If you enjoyed this tutorial you may like our ebook available on Amazon. The Hobbyist’s Guide to the RTL-SDR: Really Cheap Software Defined radio.

The post RTL-SDR Tutorial: Decoding Digital Voice (P25) with DSD appeared first on rtl-sdr.com.

The popular digital speech decoder (DSD) software has now been wrapped into a GNU Radio Companion block. Previously, DSD required use of virtual audio cables to get decoding to work with GNU Radio, but now the signal audio can be passed directly into this block.

Luke Berndt from the HackRF-dev forums has posted his work to make the functionality of DSD available to GNU Radio users in the form of a GRC block. “I have been playing around a bit and found an easy way to receive and playback digital LMR. More and more of the radio systems are going from narrow band FM to Digital. This makes it tough to listen to them on GQRX. DSD is a great program which can decoded the audio you get when you tune in a system in GQRX, but you either have to run it on another machine with a audio cable in between or figure out how to do a virtual audio cable on your machine.

Luckily, someone wrapped the DSD libraries so they can be accessed as GRC blocks. I have put together a GRC file and a Python program that make it a little easier to use the block.

If you have a chance, give them a try and let me know if they work. There is a good chance I have messed up the values in the filters or else where, but I have gotten clean audio out of it.”

Download the files from GitHub.

DSD is a Linux and Windows software program capable of decoding popular digital speech codecs such as APCO P25 and MOTOTRBO/DMR.

Via DangerousPrototypes

The post New DSD Block Available for GNU Radio appeared first on rtl-sdr.com.

Over on Reddit we’ve seen mention of an upgraded Digital Speech Decoder (DSD) program, named DSD+. The original DSD is a program that can be used in conjuction with a SDR receiving program such as SDR#, and an audio piping program like VBCable to decode digital speech, such as P25 and DMR/MOTOTRBO.

DSD+ claims to have improved decoding and audio quality capabilities. An audio sample from a weak P25 sample can be found here for DSD+, and for comparison here for the old DSD.

DSD+ can be downloaded from this megaupload link.

To run DSD+. you will need to place an MP3 encoder file lame_enc.dll into the same folder as the dsd.exe executable. This file is not included with DSD+ due to licencing. For Windows, lame_enc.dll can be downloaded from http://lame1.buanzo.com.ar/#lamewindl (Mega Mirror). Download the ZIP option, and then copy the dll file into the same folder as DSD+.

If you don’t know how to use DSD, see our tutorial on using DSD here, and if desired simply use DSD+ instead of the original DSD. (Note cygwin is not required for DSD+)

EDIT: There is now a new version of DSD+ see http://www.rtl-sdr.com/dsd-version-1-5-released/.

The post Improved Digital Voice P25 Decoding with DSD+ appeared first on rtl-sdr.com.

D-STAR or (Digital Smart Technologies for Amateur Radio) is a Frequency Division Multiple Access (FDMA) Gaussian Minimum Shift Keying (GMSK) digital voice and data protocol used in amateur radio.

Up until recently it was possible to decode D-STAR headers using either DSD 1.6 or dstar.exe and an RTL-SDR, but it was not possible to decode voice. Now amateur radio hobbyist PU2VLW has brought to our attention that the latest DSD development version 1.7 is capable of decoding D-STAR audio (his post is in Portuguese so we suggest using Google translate). He shows a video of some example D-STAR decoding which we show at the end of this post.

DSD 1.7 can currently be downloaded as source from it’s GitHub respository. Instructions for installing DSD 1.7 on Linux can be found on the post by PU2VLW and the GitHub readme. PU2VLW built DSD 1.7 in Ubuntu 10.04, noting that newer versions of Ubuntu have removed OSS (Open Sound System) support which DSD requires. He then runs SDR# on a Windows PC, tuned to a D-STAR signal, and uses an audio out cable to connect the Windows PC’s audio out to the Ubuntu PC running DSD 1.7.

Update: See this post for installing DSD 1.7 on Windows.

EDIT: There is now a version of DSD+ that can decode D-STAR. http://www.rtl-sdr.com/dsd-version-1-5-released/

The post Listening to D-STAR Digital Voice with DSD 1.7 appeared first on rtl-sdr.com.

Programmer Tyler Watt has been working on software that automatically logs each call from an RTL-SDR running DSD (Digital Speech Decoder) and then stores it in a time stamped database as an mp3 file. There is also a web front end for the database which allows public users to search and play recorded calls.

Recently Tyler updated his code by rewriting it in PHP and making it multiplatform.

The old version of his web front end in action for his local P25 calls can be viewed here, and the newer one can be found here.

The post RTL-SDR DSD Call Log Recorder appeared first on rtl-sdr.com.

The popular trunking decoding software Unitrunker now supports the RTL2832U R820T RTL-SDR directly in its new version. This means that extra SDR receiver software like SDR# is no longer required to use Unitrunker.

You can download the latest version of Unitrunker here.

In a normal radio system, one company (or talkgroup) might use a single frequency for radio communications. However, this is very inefficient as the frequency may not be in use for the majority of the time. In a trunked radio system, a small set number of frequencies are shared between a large number of talkgroups. Each radio receives a special computer controlled control channel. The control channel determines a vacant frequency that a particular talkgroup should use. This helps to make radio frequency allocations more efficient.

Because a talkgroup might switch between various frequencies often, it can make listening to a conversation difficult for radio scanners. Unitrunker can be used to decode the control channel and follow a voice conversation as it hops across various frequencies. With two RTL-SDR dongles you can set up a trunking receiver station with just Unitrunker. What follows below is a tutorial on how to set this up.

Unitrunker Voice Trunking Following Tutorial

To set up a trunking station we will assume that you have been through the Quickstart guide and thus have a working RTL-SDR setup. In addition you will need

1. 2x R820T RTL2832U RTL-SDR dongles. See the Buy RTL-SDR dongles page if you don’t already have two. You will need one dongle to receive the control channel and one dongle to receive the voice channel. Only the R820T appears to be supported at the moment.
2. The Unitrunker software (Choose the latest version from http://www.unitrunker.com/download/)
3. One antenna that splits into two connections for the two dongles, or two antennas that can receive the trunking frequencies you are interested in.

Now follow these steps to set up Unitrunker with the RTL2832U.

Setting up the Signal (Control Channel) Receiver

1. First determine a trunking control channel that you are interested in monitoring. You can use SDR# or a similar program to search for these first. They will be signals that are continuously transmitting with no breaks. Here are some examples of some common trunking modes. The are commonly found in the 400 and 800 MHz bands.

APCO P25	EDACS96
Motorola 2F1D	MPT 1327

2. Plug in both dongles and then open Unitrunker.
3. Press the ‘Add new receiver’ button , and then on the bar that pops up click on the RTL2832 button.

4. In the new window that pops up change the Role to Signal.
5. Under the Signal heading change the RTL Device to the stick that be used for the control channel.
6. Type in your dongles frequency offset in PPM in Correction.
7. Make sure that Mute is checked.
8. Change the Park value to the frequency of the trunking channel that you wish to monitor.
9. Under Decode check all the protocols that you are interested in listening to.
10. Now at the top of this window press the Play button . A new window should soon pop up and the value of the Protocol setting under the Decode heading should change to the trunking protocol detected.If the window does not pop up, either increase the Gain value or turn on the Auto Gain setting. If no window still pops up, set the Audio Output setting to your speakers and uncheck the mute button. Listen to see if the trunking channel is being correctly played through your speakers. If not, you may need to fine tune the frequency further by adjusting the Correction value.

11. If the signal is strong enough, a new window should pop up. This new window shows the frequencies in use, and logs each call. If the frequencies are not showing, click the ‘Wizard’ button  whose icon looks like a calculator. Then choose the system used in your country. If unsure, try ‘Standard’ first.

12. Close the Receiver R820T options window for the signal channel and go back to the main Unitrunker Window.

Setting up the Voice Channel Receiver

Now that we have added the signal receiver and decoder we will add the voice receiver.

1. Press the ‘Add new receiver’ button  once again, and then on the bar that pops up click on the RTL2832 button.
2. This time for the role choose ‘Voice’.
3. For the RTL Device, choose your second RTL-SDR dongle.
4. Set the gain and PPM offset appropriately.
5. Choose the Audio Output as your speakers and make sure that Mute is not checked.
6. Set the ‘Park’ frequency to zero.
7. If desired, set the squelch to a value that is similar to what you might use in SDR#. The squelch will stop static from playing when there is no voice signal. You may wish to leave this at zero for now, and then tune it with trial and error later when you have everything going.

8. Press the Play button .

Enabling Unitrunker Following

Now we will make sure that Unitrunker is set to allow the voice receiver to follow calls from the signal channel.

1. Go back to the main Unitrunker window and click on the Option tab at the bottom of the window.
2. Make sure that Enable is checked under Listen. This will allow the voice channel to follow the trunking information from the control signal.

At this point your trunking receiver should now be up and running!

Decoding Digital Voice (P25/DMR/Mototrbo/NXDN/ProVoice)

Decoding of unencrypted digital voice signals like P25/DMR/Mototrbo can be set up in the same way as the analog system shown above. However, instead of outputting audio to the speakers, audio should be output to a virtual audio pipe such as Virtual Audio Cable (VAC) or VB Cable using the Digital Output audio selection in Unitrunker. Then DSD+ should be used to listen to the audio pipe. Audio will only be piped to the Digital Output during a digital call.

DSD+ is a program that is capable of decoding digital voice protocols such as P25, DMR/Mototrbo, NXDN and ProVoice. It is not capable of decoding encrypted digital voice channels. DSD+ is similar to DSD 1.6, but it has vastly improved decoding in terms of voice quality. You can find the download for DSD+ here. Be sure to follow the installation instructions on that page involving downloading the lame_enc.dll dll file.

To run DSD+ open a command prompt from Start->All Programs->Accessories->Command Prompt, and navigate to the folder where DSD+ is located. For those who are not familiar with the command prompt, use the ‘cd’ command to change directories within command prompt. For example, if your DSD+ folder is located in c:\Radio\DSD+, you would type in command prompt ‘cd c:\Radio\DSD+’.

Then in command prompt type ‘dsd -i1M’, where the number after the -i is the number of your audio pipe. If your audio pipe is set as your default sound device in the Windows audio recording properties it will be device 1, otherwise it may be device 2 or higher. You can use ‘dsd -h’ to see more options for DSD+.

Make sure that the Deemphasis option in Unitrunker is turned OFF for the voice receiver to make it work with DSD+.

Tips:

• For digital voice you may need to play with the Windows volume settings of your audio pipe to improve decoding.
• You will require a decent antenna that is capable of receiving the trunking frequencies you are interested in.
• Unitrunker can be coupled with a radioreference.com account to get trunk group names.

If you enjoyed this tutorial you may like our ebook available on Amazon. The Hobbyist’s Guide to the RTL-SDR: Really Cheap Software Defined radio.

The post RTL-SDR Tutorial: Following Trunked Radio with Unitrunker appeared first on rtl-sdr.com.

Back in March we showed a beta version of Tyler Watts ScanEyes trunked call log recorder software. Now Tyler has released a more complete version of his ScanEyes software. A live version of the software can be found at sdrscan.com. ScanEyes works by using a software defined radio such as the RTL-SDR combined with trunking following software Unitrunker and optional P25 decoder DSD/DSD+ to archive all calls made on a trunked radio system. A user can then later go into the web interface and view and listen to archived calls.

The post ScanEyes: Software for Visualizing, Listening to and Archiving Trunked Radio Traffic appeared first on rtl-sdr.com.

The developer over at rtl-sdr.ru has released a new plugin for SDR# (note in Russian – use Google translate) which allows the digital voice decoder DSD+ to be controlled via a GUI interface from SDR#. To use this plugin you will need to have a copy of DSD+ already downloaded as you will need to point the plugin to the DSD+ install directory. You will also need to have virtual audio cable software such as VAC or VBCable setup.

Information on downloading and setting up DSD+ can be found here.

The post New SDR# Plugin: GUI Interface for DSD+ appeared first on rtl-sdr.com.

Over on YouTube user John Miller has uploaded a video showing an example of DSD+ decoding an NXDN96 voice signal. NXDN is a digital voice protocol by developed by Kenwood that is often used by public safety organizations.

John uses SDR# to receive the NXDN signal and then pipes the audio to DSD+ using Virtual Audio Cable for decoding.

The post Decoding NXDN using DSD+ and an RTL-SDR appeared first on rtl-sdr.com.

Version 1.5 of Digital Speech Decoder Plus (DSD+) has been released. DSD+ is a popular Windows software tool used for decoding digital speech such as P25 with the RTL-SDR. The latest version comes with a simple GUI interface that has an event log that shows call target and source ID history and an audio waveform plot which can help determine if DSD+ is receiving audio correctly. This version of DSD+ has the ability to decode the following protocols.

• D-STAR
• NXDN4800
• NXDN9600
• DMR/MotoTRBO
• P25 Phase 1
• X2-TDMA
• ProVoice

In addition to the above, the new version comes with an LRRP decoder and display program which should allow you to see on a map the GPS location of broadcasting radios.

DSD+ V1.51 can be downloaded from this link. The forum thread on RadioReference where the developer releases and discusses the DSD+ software can be found here.

This version of DSD+ comes with all the files needed to make it run already. To use DSD+ V1.5 simply extract the zip file into a folder and double click on DSDPlus.EXE. DSD+ will listen to your default audio device that is set in the Windows sound recording properties. Simply tune to a digital voice signal in SDR# or any other SDR receiver and set the output audio settings accordingly. To start the LRRP display program simply open LRRP.exe.

The post DSD+ Version 1.5 Released appeared first on rtl-sdr.com.

The latest version of Digital Speech Decoder+ (DSD+) has just been released, bringing it up to version 1.071. There appears to be no changelog, so we are unsure as to what is new, but one obvious change is that they now include a new program called FMP which is a simple NFM demodulator, similar to rtl_fm, although it does have a GUI with point and click tuning. FMP can be used as a replacement for SDR# or similar software, and is especially useful to use on low end devices such as netbooks.

An active discussion on the latest release of this software can be found in this thread on the RadioReference.com forums.

DSD+ is a Windows program which can be used to decode and listen to digital voice protocols such as D-STAR, NXDN4800, NXDN9600, DMR/MotoTRBO, P25 Phase 1, X2-TDMA and ProVoice with an RTL-SDR or other radio. On some DMR systems you may also be able to use the included LRRP software, which allows you to view the GPS locations of broadcasting radios. The last major release was version 1.05.

The DSD+ team are now also offering a “fast lane” early access program, which for a small donation will allow you to have early access to new and upcoming DSD+ features. They aim to release a new update to donators every 7 to 30 days, while stable public releases will continue to be released every 4 to 6 months. The donation costs $10 for one year of early access, and $25 for lifetime updates. Some features they are currently working on include:

• Better tablet support
• IDAS/NEXEDGE/Cap+/Con+/TIII trunk voice following
• Per-call audio recordings
• Other needed DSD+ upgrades
• FMP upgrades
  • Squelch
  • Drift tracking
  • Selectable sampling rates
  • Adjustable windows sizes
  • TCP client/server mode (eliminates VAC / VB-C)
  • Multiple VFOs
  • Airspy support

The post New Version of Digital Speech Decoder DSD+ 1.071 Released appeared first on rtl-sdr.com.

DSD+ stands for Digital Speech Decoder Plus and is a software program that can allow you to decode digital voice signals such as P25 and MotoTRBO/DMR. DSD+ is under continual development, and in their last public update they began offering early access to the latest DSD+ features in development through their fast lane subscription. The fast lane subscription costs $10 USD for one year and $25 for unlimited early access. Information about joining the fast lane service can be found in the readme file of the latest DSD+ 1.074 public release.

Over on YouTube user John Miller has been testing the latest early access version DSD+ 1.08t. This new version adds trunking support which allows you to follow conversations. Previously other software like Unitrunker was required to follow the trunking signal. On YouTube John has uploaded a video first showing trunking in action, and a second video showing how to set up DSD+ 1.08t for trunking.

The post Trunking with the Latest DSD+ 1.08t Fast Lane Version appeared first on rtl-sdr.com.

DSD+ (Digital Speech Decoder+) is a popular decoding tool that can be used to listen to P25, DMR and other unencrypted digital speech signals. Recently DSD+ has been updated from version 1.074 to version 1.101.

The new version brings several changes, including the ability to decode Hytera Extended Pseudo Trunk (XPT) systems, Airspy compatibility, performance improvements and a TCP/IP link from FMP to DSD+ (no longer need to use a virtual audio cable). The full change log is as follows:

DSD+: Fixed AMBE tone frame audio generation.

FMA: Added Airspy-compatible FMP (FMPA.exe)

DSD+: Significant reduction in CPU usage when monitoring busy control channels. Improvement will be most noticeable on low power processors.

DSD+: Detection and decoding of Hytera Extended Pseudo Trunk (XPT) systems.

DSD+: The DSD+ -i command line parameter can contain an IPV4 address; this lets DSD+ connect to a copy of FMP that is running on a different PC in your local network or on the Internet

Example: DSDPlus -i192.168.1.150:20001

DSD+: NEXEDGE radio alias editing

DSD+ now marks auto-generated NEXEDGE radio aliases in the DSDPlus.radios file by prepending an asterisk like so:

NEXEDGE, … yyyy/mm/dd hh:mm, *”aliastext”

If you edit a NEXEDGE alias, you must remove the asterisk; this tells DSD+ that the new alias text is NOT auto-generated and DSD+ will not replace it with OTA alias text

FMP: FMP command line processing

The FMP command line format has been modified and is now similar to the DSD+ command line. A summary is listed here:

FMP rev 1.4t

Usage:
FMP [options] Normal operation
FMP -h Show help

Options:
-i<num> RTL SDR device number (1-255) [-i1]
-o<num> Output audio device (1-255) [-o1]
-o<port> Output audio TCP port (256-65535)
-P<num> PPM value (-999.9-999.9) [-P0.0]
-g<num> RF gain (dB) [max]
-f<MHz> Initial tuned frequency [-f99.9]
-b<kHz> Initial filter bandwidth (4, 7, 9.5, 12.5) [-b7]
-z<num> Show zoomed spectrum (0-1) [-z1]
-e<num> Enable/disable economy mode (0-1) [-e1]
-n<num> Select noise filter (0-2) [-n0]
-v<num> Set volume level (0-500) [-v100]
-s<num> Enable/disable scanner mode (0-1) [-s0]
-wsl<v>.<h> Spectrum window location [-wsl50.50]
-_<num> Minimize windows at startup; bitmapped
-rv Role is trunk voice channel monitor

-rv puts FMP into voice following mode (same as pressing ‘V’ in FMP)

Any shortcuts or batch files that run FMP will have to be modified to match the new command line format.

DSD+: Less processor loading (probably only noticeable on very slow processors)

DSD+: Much faster groups/radios files loading/saving

DSD+: Editing existing radio aliases

In previous versions of DSD+, editing of pre-existing radio aliases can not be done with an external text editor while DSD+ is running; only radio records with no alias text can be edited

With DSD+ 1.092, existing radio alias text can be edited in an
external text editor while DSD+ is running; DSD+ will load and display any updated radio aliases

DSD+: A DSDPlus.radios file corruption bug has been fixed

DSD+: A command line option to add system details to event log entries has been added

-E Add NAC/RAN/DCC/RAS data to event log file entries

DSD+: Decoding of more DMR and TIII messages has been added

DSD+: A symbol recovery bug has been fixed

DSD+: Con+ handling has been modified; previous versions of DSD+ would create “DMR” entries in the DSDPlus.groups and DSDPlus.radios files for traffic on monitored voice channels; DSD+ 1.090 creates “Con+” entries; if you have “DMR” entries with nonzero NID fields, you should either bulk delete them or change their protocol string from “DMR” to “Con+”; Notepad has a simple search/replace function that can be used to do this

DSD+: A command line option to minimize windows at startup has been added

-_<num> Minimize selected windows at startup (bitmapped, 0-15) [-_0]

value window

1 console
2 source audio
4 channel activity
8 event log

sum values to minimize multiple windows

DSD+: Several high contrast display modes have been added

-H<num> High contrast mode (bitmapped, 0-63) [-H0]

two bits are used per graphical window; pressing ‘H’ in a window will cycle it to the next display mode; pressing ‘W’ displays the current -H<num> value in the event log window

DSD+: Control of AMBE and IMBE unvoiced audio levels has been added

-UA<num> AMBE unvoiced speech level (0-100) [-UA50]
-UI<num> IMBE unvoiced speech level (0-100) [-UI50]

pressing ‘A’/’a’/’I’/’i’ will also adjust the levels;
lower levels may reduce the “underwater” sound of some comms

DSD+: DSD+ can get its raw audio source from FMP via a TCP link instead of via Virtual Audio Cable or VB-Cable

-i<TCPport> FMP TCP link port number (256-65535)

linking FMP to DSD+ via VAC or VBC is deprecated; please use the TCP
link feature instead; any port number between 10000 and 65000 should be fine

DSD+: DSD+ can record separate .wav files for each voice call

-P<wav|mp3> Also create per-call wav or mp3 files

the file names encode metadata:

time
duration
protocol
NID
site number
NAC/RAN/DCC/slot
call type (group/private)
target
source

note: per-call mp3 files are not supported at this time

FMP: A command line option to minimize windows at startup has been added

-_<num> Minimize selected windows at startup (bitmapped, 0-3) [-_0]

value window

1 console
2 spectrum display

The post DSD+ Updated to Version 1.101 appeared first on rtl-sdr.com.

DSD+ (Digital Speech Decoder+) is a popular Windows tool that can be used together with an RTL-SDR to decode digital speech signals such as P25 and DMR. There is unfortunately no version for OSX.

However, recently on YouTube user Matthew Miller has uploaded a video showing DSD+ running with CubicSDR on OSX. To do this he used a utility called “Wine Skin” which creates a wrapper that allows Windows software to run on a MAC computer running OSX. This means that DSD+ can be run on directly OSX without the need to use a virtual machine with Windows installed on it.

The post Decoding DMR on OSX using a RTL SDR and DSD Plus appeared first on rtl-sdr.com.

Last week we posted about how Matthew Miller deomnstrated that he was able to get the Windows digital speech decoder (DSD+) software running under OSX with WineSkin. DSD+ allows you to decode digital voice signals such as P25 and Motorola DMR. A few users asked how to actually use WineSkin to create a wrapper, so now Matthew has uploaded a new tutorial video showing how to use WineSkin to get DSD+ running on OSX.

In the video he shows how to download and install WineSkin, and how to create a wrapper that allows DSD+ to run on OSX. The process is relatively simple and only involves using GUI based tools.

The post How to use DSD+ with WineSkin on OSX appeared first on rtl-sdr.com.

Over on YouTube user AVT Marketing has uploaded a five part video series that very clearly and slowly shows how to use an RTL-SDR to set up trunking and digital voice monitoring. In the videos he uses SDR#, Unitrunker, DSD+ and VBCable for the monitoring.

The first video in the series shows a brief overview of the digital trunking voice set up, and explains a bit about digital voice communications. The second video shows how to install an RTL-SDR, and walks you through downloading Unitrunker and DSD+. The third video is a tutorial about SDR# and also explains how trunking radio systems works. The fourth video shows how to install Unitrunker, DSD+, VBCable, and how to configure each program. Finally the fifth and last video in the series shows the final steps in using Unitrunker and DSD+.

This looks like a very good video series, especially for those that like to see every step in the process played out in full.

Over on YouTube user John Miller has uploaded a video showing an example of DSD+ decoding an NXDN96 voice signal. NXDN is a digital voice protocol by developed by Kenwood that is often used by public safety organizations.

John uses SDR# to receive the NXDN signal and then pipes the audio to DSD+ using Virtual Audio Cable for decoding.

Version 1.5 of Digital Speech Decoder Plus (DSD+) has been released. DSD+ is a popular Windows software tool used for decoding digital speech such as P25 with the RTL-SDR. The latest version comes with a simple GUI interface that has an event log that shows call target and source ID history and an audio waveform plot which can help determine if DSD+ is receiving audio correctly. This version of DSD+ has the ability to decode the following protocols.

• D-STAR
• NXDN4800
• NXDN9600
• DMR/MotoTRBO
• P25 Phase 1
• X2-TDMA
• ProVoice

In addition to the above, the new version comes with an LRRP decoder and display program which should allow you to see on a map the GPS location of broadcasting radios.

DSD+ V1.51 can be downloaded from this link. The forum thread on RadioReference where the developer releases and discusses the DSD+ software can be found here.

This version of DSD+ comes with all the files needed to make it run already. To use DSD+ V1.5 simply extract the zip file into a folder and double click on DSDPlus.EXE. DSD+ will listen to your default audio device that is set in the Windows sound recording properties. Simply tune to a digital voice signal in SDR# or any other SDR receiver and set the output audio settings accordingly. To start the LRRP display program simply open LRRP.exe.

The latest version of Digital Speech Decoder+ (DSD+) has just been released, bringing it up to version 1.071. There appears to be no changelog, so we are unsure as to what is new, but one obvious change is that they now include a new program called FMP which is a simple NFM demodulator, similar to rtl_fm, although it does have a GUI with point and click tuning. FMP can be used as a replacement for SDR# or similar software, and is especially useful to use on low end devices such as netbooks.

An active discussion on the latest release of this software can be found in this thread on the RadioReference.com forums.

DSD+ is a Windows program which can be used to decode and listen to digital voice protocols such as D-STAR, NXDN4800, NXDN9600, DMR/MotoTRBO, P25 Phase 1, X2-TDMA and ProVoice with an RTL-SDR or other radio. On some DMR systems you may also be able to use the included LRRP software, which allows you to view the GPS locations of broadcasting radios. The last major release was version 1.05.

The DSD+ team are now also offering a “fast lane” early access program, which for a small donation will allow you to have early access to new and upcoming DSD+ features. They aim to release a new update to donators every 7 to 30 days, while stable public releases will continue to be released every 4 to 6 months. The donation costs $10 for one year of early access, and $25 for lifetime updates. Some features they are currently working on include:

• Better tablet support
• IDAS/NEXEDGE/Cap+/Con+/TIII trunk voice following
• Per-call audio recordings
• Other needed DSD+ upgrades
• FMP upgrades
  • Squelch
  • Drift tracking
  • Selectable sampling rates
  • Adjustable windows sizes
  • TCP client/server mode (eliminates VAC / VB-C)
  • Multiple VFOs
  • Airspy support

DSD+ stands for Digital Speech Decoder Plus and is a software program that can allow you to decode digital voice signals such as P25 and MotoTRBO/DMR. DSD+ is under continual development, and in their last public update they began offering early access to the latest DSD+ features in development through their fast lane subscription. The fast lane subscription costs $10 USD for one year and $25 for unlimited early access. Information about joining the fast lane service can be found in the readme file of the latest DSD+ 1.074 public release.

Over on YouTube user John Miller has been testing the latest early access version DSD+ 1.08t. This new version adds trunking support which allows you to follow conversations. Previously other software like Unitrunker was required to follow the trunking signal. On YouTube John has uploaded a video first showing trunking in action, and a second video showing how to set up DSD+ 1.08t for trunking.