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DMR <-> P25

va3czk@...
 

Good morning,
I'm just getting my head wrapped around this and trying to set up P25<-->DMR and here is what I have done so far.
- P25 Gateway up and running and conectend to the reflector
- MMDVM_Bridge P25.ini modified with my and BM credentials, both P25 and DMR enabled.
When both running I can see traffic from both sides flowing to MMDVM_Bridge in the log file.
 
What else is missing to make this combo work.

73' Jerry va3czk
 
Steve N4IRS
 

Jerry,
You are on the right track building from the outside in. P25 to DMR requires transcoding. That is your next step. P25 to DMR looks like this:

P25Reflector <-> P25Gateway <-> MMDVM_Bridge <-> Analog_Bridge_1 <-> Analog_Bridge_2 <-> MMDVM_Bridge <-> BrandMeister

The 2 copies of Analog_Bridge are connected "back to back" to transcode P25 to DMR.   Analog_bridge_1 is configured for IMBE (P25) and Analog_Bridge_2 is configured for AMBE (DMR).

[USRP] Analog_Bridge_1                  [USRP] Analog_Bridge_2
address = 127.0.0.1                     address = 127.0.0.1
txPort = 32001                          txPort = 34001
rxPort = 34001                          rxPort = 32001
aslAudio = AUDIO_UNITY                  aslAudio = AUDIO_UNITY
agcGain = -20                           agcGain = -20
dmrAudio = AUDIO_UNITY                  dmrAudio = AUDIO_UNITY
dmrGain = 0.35                          dmrGain = 0.35

Above is the [USRP] stanza from each copy of Analog_Bridge. Notice the "crossover" of the TX and RX ports.

In the above diagram, You only need 1 copy of MMDVM_Bridge. P25 points to Analog_Bridge_1 and DMR points to Analog_Bridge_2

Hope this helps,

73, Steve N4IRS

On 07/06/2018 06:03 AM, va3czk@... wrote:
Good morning,
I'm just getting my head wrapped around this and trying to set up P25<-->DMR and here is what I have done so far.
- P25 Gateway up and running and conectend to the reflector
- MMDVM_Bridge P25.ini modified with my and BM credentials, both P25 and DMR enabled.
When both running I can see traffic from both sides flowing to MMDVM_Bridge in the log file.
 
What else is missing to make this combo work.

73' Jerry va3czk
 
va3czk@...
 

Thanks Steve,

73' Jerry VA3CZK
va3czk@...
 

Hi Steve,

is there any recommended value for the audio level between DMR and P25 that works best?
Getting a little bit of distortion on both sides ?

Thanks,

J

[USRP]
server = 127.0.0.1                      ; IP address of Allstar/Asterisk
toASLPort = 34001                       ; Analog_Bridge <-- ASL
fromASLPort = 32001                     ; Analog_Bridge --> ASL
aslAudio = AUDIO_UNITY                  ; Audio to ASL (AUDIO_UNITY, AUDIO_USE_AGC, AUDIO_USE_GAIN)
agcGain = -20                           ; Gain (in db) of the AGC filter
dmrAudio = AUDIO_UNITY                  ; Audio from ASL (AUDIO_UNITY, AUDIO_USE_GAIN, AUDIO_BPF)
dmrGain = 0.35                          ; Gain factor of audio from ASL (0.0-1.0)
 
Steve N4IRS
 

Change to AUDIO_USE_GAIN and set the value to less then 1. I would start with .5 if it's hot and adjust up or down as needed.

Steve

On 07/12/2018 06:49 PM, va3czk@... wrote:
Hi Steve,

is there any recommended value for the audio level between DMR and P25 that works best?
Getting a little bit of distortion on both sides ?

Thanks,

J

[USRP]
server = 127.0.0.1                      ; IP address of Allstar/Asterisk
toASLPort = 34001                       ; Analog_Bridge <-- ASL
fromASLPort = 32001                     ; Analog_Bridge --> ASL
aslAudio = AUDIO_UNITY                  ; Audio to ASL (AUDIO_UNITY, AUDIO_USE_AGC, AUDIO_USE_GAIN)
agcGain = -20                           ; Gain (in db) of the AGC filter
dmrAudio = AUDIO_UNITY                  ; Audio from ASL (AUDIO_UNITY, AUDIO_USE_GAIN, AUDIO_BPF)
dmrGain = 0.35                          ; Gain factor of audio from ASL (0.0-1.0)
 
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