Unitrunket using R820T

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Joined: Sat Apr 26, 2014 4:00 pm

Unitrunket using R820T

Post by G6VBJ » Sat Apr 26, 2014 4:13 pm

Hi Guys first post here so please forgive stupid questions etc.

I have installed the drives and unitrunker and set it up as per the tutorial. I am trying to get the system to follow and decode an MPT1327 system. I know the frequency of the control channel. However when I run the program and set the receiver to run, it never decodes anything.

Anyone have any thoughts??



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Joined: Thu Apr 17, 2014 5:44 pm

Re: Unitrunket using R820T

Post by scannergoderich » Sat Apr 26, 2014 7:34 pm

I believe you need to send the digital audio to a decoder using something like a virtual audio cable to send the audio to a program called DSD PLUS
here is what it can decode: (NON-Encrypted signal only)

The latest version (1.6) supports the following formats and modulation types:
P25 Phase 1
ProVoice EDACS Digital voice
X2-TDMA - Motorola public safety TDMA system with P25 style signaling (mostly based on DMR)
DMR/MOTOTRBO - Digital Mobile Radio standard
NXDN - 9600 baud (12.5 kHz) NEXEDGE and 4800 baud (6.25 kHz) NEXEDGE/IDAS
D-STAR - The Github version of dsd/mbelib can parse and play back D-STAR traffic.
C4FM modulation
GFSK modulation (including GMSK and other filtered 2/4 level FSK)
QPSK modulation (sometimes marketed as "LSM")
The following formats are currently under investigation or development:
P25 Phase 2 - standard not finalized yet, vocoder is supported by mbelib
OpenSky - four slot format vocoder may be supported by mbelib. Will not be supportable if it is determined that voice encryption is standard
Other formats will only be considered if high quality samples of the signals are made available for download by the developers. Samples must be from a discriminator tap, .wav format, 48000Hz, 16 bits per sample, mono.

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Joined: Sat Apr 26, 2014 8:32 pm

Re: Unitrunket using R820T

Post by unitrunker » Sat Apr 26, 2014 8:37 pm

Hi Peter;

Make sure MPT1327 is checked under the Decode section of your signal receiver.

Look at the waveform on the Scope tab. Make sure the waveform is vertically centered. You can adjust the warp / correction factor for this. The program accepts decimal amounts.

As you likely know, DSD and DSD+ don't do anything for MPT1327.

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