Hytera Pseuso Trunk/XPT systems
Posted: Thu Nov 16, 2023 1:34 pm
Good morning group:
I hope this is the correct discussion area to post, seemed most appropriate of "general"
My Retevis RT3S and MD UV380 radio with OpenGD77 firmware have been awesome for helping finding and listening to DMR repeaters and systems I had only been able to receive previously by using DSD+, and then having to program it into a DMR radio with all the information to use it.
For standard repeaters and simplex, this has been fine.
Recently, I've found what DSD+ is showing as an 'XPT' system. This is not an amateur radio system however, it's used by the local University where my wife works, so I thought it would be fun to see what traffic is handled on it. It gives brief busts of data at about a 30% duty cycle, I assume like Moto's Capacity Plus and LTR to give a subscriber radio a "rest channel" to sit on.
To the point, I am not able to use the data derived from either DSD+ or my RT3S into any other radio and hear anything. I also find it interesting how DSD+ and OpenGD77 handle the DMR information and decode it for display differently.
DSD+, for instance, will display Talkgroup 1 as active. My RT3S will show a much longer talkgroup ID like 1043901. Radio IDs are also altered and displayed differently, however whatever radios the school is using will show up on my RT3S with a user ID alias that is believable like "COM 1" etc.
At any rate, if I put in the longer group into a different radio, in my case a Moto XPR5500 and Retevis RT73, the radio won't decode anything. Same for the shorter group ID given by DSD+.
If I program the long group ID into the RT3S, it receives and displays the group as expected... but it will also decode everything, including the short data burts, often coming through like dead-air or noise.
Has anyone got insight on the Hytera Pseudo Trunk or XPT systems enough to know if the data is proprietary enough to not be easily programmed into a non-Hytera pseudo trunk/XPT radio?
A decade ago when I was much more active in DMR scanning/decoding, a regional DMR Connnect Plus system interested me since it was something new taking over in the ashes of Nextel. I was easily able to listen to various groups- conventionally, just by having the frequency, CC, slot, and group... it would just work, wouldn't do any sort of trunking obviously, but any DMR radio could be programmed that way and decode the audio. Maybe this isn't the case, but I would like to think *something* is not decoding the group ID properly since I'm getting mixed results with the resources I have available to me.
-Josh
I hope this is the correct discussion area to post, seemed most appropriate of "general"
My Retevis RT3S and MD UV380 radio with OpenGD77 firmware have been awesome for helping finding and listening to DMR repeaters and systems I had only been able to receive previously by using DSD+, and then having to program it into a DMR radio with all the information to use it.
For standard repeaters and simplex, this has been fine.
Recently, I've found what DSD+ is showing as an 'XPT' system. This is not an amateur radio system however, it's used by the local University where my wife works, so I thought it would be fun to see what traffic is handled on it. It gives brief busts of data at about a 30% duty cycle, I assume like Moto's Capacity Plus and LTR to give a subscriber radio a "rest channel" to sit on.
To the point, I am not able to use the data derived from either DSD+ or my RT3S into any other radio and hear anything. I also find it interesting how DSD+ and OpenGD77 handle the DMR information and decode it for display differently.
DSD+, for instance, will display Talkgroup 1 as active. My RT3S will show a much longer talkgroup ID like 1043901. Radio IDs are also altered and displayed differently, however whatever radios the school is using will show up on my RT3S with a user ID alias that is believable like "COM 1" etc.
At any rate, if I put in the longer group into a different radio, in my case a Moto XPR5500 and Retevis RT73, the radio won't decode anything. Same for the shorter group ID given by DSD+.
If I program the long group ID into the RT3S, it receives and displays the group as expected... but it will also decode everything, including the short data burts, often coming through like dead-air or noise.
Has anyone got insight on the Hytera Pseudo Trunk or XPT systems enough to know if the data is proprietary enough to not be easily programmed into a non-Hytera pseudo trunk/XPT radio?
A decade ago when I was much more active in DMR scanning/decoding, a regional DMR Connnect Plus system interested me since it was something new taking over in the ashes of Nextel. I was easily able to listen to various groups- conventionally, just by having the frequency, CC, slot, and group... it would just work, wouldn't do any sort of trunking obviously, but any DMR radio could be programmed that way and decode the audio. Maybe this isn't the case, but I would like to think *something* is not decoding the group ID properly since I'm getting mixed results with the resources I have available to me.
-Josh