This is a tutorial on how to link UniTrunker with HDSDR to make HDSDR a trunk tracking program.
This can be used to turn a $20 RTL2832 DVB-T USB stick into a digital truck tracker to listen to APCO-25 for eg.
First download and install UniTrunker. Unitrunker
Then download and install HDSDR. HDSDR Homepage
Install and set up all your drivers for HDSDR.
If your using funcube or a DVB-T stick the drivers are here - USRP Interfaces - SpenchWiki
Now you will need to down load and install com0com. Null-modem emulator (com0com) - virtual serial port driver for Windows
com0com is a virtual serial port driver for Windows and will be needed to set up virtual com ports for unitrunker and HDSDR to talk on.
Next if you would like to listen to digital trunking system download and install Digital speech decoder. This is optional. Digital Speech Decoder (software package) - The RadioReference Wiki
Now download the attached file UniLinker. This is a small program i wrote to link the output of UniTrunker with input of HDSDR.
Now for the the software setup.
Create a total of 4 virtual com ports with com0com for example com5 com6 and com 7 com8.
You will need 4 ports because each set has an input and output port.
Basically the setup should look something like this:
Unitrunker > com5-com6 -> UniLinker -> com7-com8 -> HDSDR.
UniTrunker is setup to output on com5
com 5 is connect to com6 with com0com
The linking program UniLinker is setup to listen on com6
The linking program is then setup to output on com7
com7 is connect to com8 with com0com
and last but not least HDSDR is setup to listen on com8.
Now the setup for UniTrunker:
Make two receivers :
One that is a Discriminator tap from your Mic line.
The second is a control receiver with the following settings
Port:com5 if you are using the above example.
MODE : AR-ONE
Stop Bite : 1
P25:X is this is the system you are listening to.
Also under the main options tap check Listen.
UniLinker and enter your input and output ports.
For the above example it will be com6 and com7.
Run HDSDR and under options setup CAT to HDSDR
Port: com 8 is using the above example.
Then check Activated.
HDSDR will know track the trunking system frequency as they are fed from UniTrunker.
You can now run Digital Speech Decoder if needed to decode digital.
I know this looks like a lot of steps but its really quite simple to setup once you get the hang of it.
I will make a video to demonstrate this operation when I get some more free time.
Also if anyone has any issues or features they need added to UniLinker please let me know and I will work on it as soon as I can.
Thanks and enjoy.
Update I am unable to upload UniTrunker because the file is slightly to big for the prerequisite. If an admin can email or msg me I can Email it to you so it can be uploaded. Thanks.