DSDPlus Need help - DSDplus won't decode with SDRplay RSPdx

[scanphreak]

What will XPT LCNs do for anyone? Just curious.

I have a BCD325P2 that I have all of the frequencies programmed in for this system, but in order to properly track all of the conversations on the system, I have to enter the sites frequencies in along with the LCN. (XPT functions like a MotoTRBO DMR system) If I am in scan or search mode, I never hear any voice traffic. But if I put the scanner on hold on say 461.3250 it'll sit there and I will occasionally hear voice traffic along with the talkgroup ID.

All of the other DMR systems in my area have confirmed LCNs on RRDB and the scanner tracks all of the calls just fine. So because the BCD325P2 does not have an LCN FINDER built in, I read somewhere that you could use DSD+ to perform that function, and well here I am, day 3 with DSD+ on my computer, trying to get this to work.

 

[slicerwizard]

LCNs are used to translate control channel messages (voice call grants) to actual radio frequencies so a receiver can tune to the voice calls. I believe that XPT doesn't have control channels; instead it's more like a digital version of LTR and therefore uses home channels. I don't recall ever seeing that any scanner understands XPT messages and would use them to steer to voice calls; if that's the case, having correct LCNs would be useless anyway. I would think that one would simply program all of the site channels as conventional DMR and scan them, but I'm not an expert. I'd ask in the Uniden forum how one should deal with an XPT system.

 

[thewraith2008]

In documentation I have read on the DMR Hytera XPT, there can be up to 8 repeaters used.
These are probably just numbered 1-8 with the slot also indicated.
XPT seems to loosely be similar to CAP+ in the sense of the use of rest channel (or for XPT: Free repeater channel) for next call setup.
Like CAP+, you would need to find the associated frequency for each channel.

If DSD+ ever decided to add support for XPT trunking it would probably stick with they're LSN system which would be 1-16 which would not suit a scanner I would think.

 

[R0am3r]

I periodically monitor the Turning Stone Casino here in Upstate NY. The casino XPT system uses four frequencies that each send a signal burst every 5 - 10 seconds. The transmissions appear to function like a typical single frequency DMR system, so you can monitor the frequencies independent of each other. From what I have seen, the LCNs are meaningless. That is why I suggested using LCN of 0 for the Uniden scanners. Several smaller casinos nearby also use XPT systems and they operate in a similar manner to Turning Stone.

 

[scanphreak]

I periodically monitor the Turning Stone Casino here in Upstate NY. The casino XPT system uses four frequencies that each send a signal burst every 5 - 10 seconds. The transmissions appear to function like a typical single frequency DMR system, so you can monitor the frequencies independent of each other. From what I have seen, the LCNs are meaningless. That is why I suggested using LCN of 0 for the Uniden scanners. Several smaller casinos nearby also use XPT systems and they operate in a similar manner to Turning Stone.

This casino is using 5 frequencies. I had the system programmed in using the MotoTRBO/DMR system choice, and when programming in the frequencies it prompted for an LCN. I left them as 0. If I begin scanning I never hear anything, but if I hold on any of the 5 frequencies I'll hear voice transmissions with tg id's. I miss conversations by sitting on one frequency though. This is what I'm trying to fix. I was under the impression that if xpt was like mototrbo I would program it as such. But so far I've been unable to get it to work.

And now it sounds like I've wasted time trying to use DSD+ to get this system up on the RRDB. But it's not a total loss. I've had this DSDPlay sitting in a box for a year now never using it.