SDRTrunk and LTR Systems

[rkillins]

I want to map out a local LTR system and I think SDRTrunk might be a good tool.
I know one frequency that I am confident exists in the system. When I monitor the frequency on a scanner I can hear the tell-tale click. I entered it in my playlist and set it up as an LTR system.

SDR indicates the channel as idle, no lie. The Activity Summary says:
Decoder: LTR STandard
Monitored LCN: 13
Active LCNs: *Insufficient data*
Talkgroups: None

Am I doing this right? Or do I have to enter all the suspected channels of the system? If so, would I do that the same way I submitted the initial frequency?

 

[cg]

There is nothing that tells the program what the other channel are and what their respective LCNs are so you need to do it. You need to find out other frequencies in the system and match the frequency with the correct LCN.

chris

 

[rkillins]

Thanks CG. So I would enter all the assumed frequencies and check them all to be monitored? Each one, once they become active will return the respective LCN in the Activity Summary of that "channel".

Is it safe to assume then that SDRTrunk (or any software) will not find system frequencies, that they need to be known in order to identify their respective frequencies. Will SDRTrunk track this as an LTR system with just the known frequencies and discovered LCNS? Or do I need to set up the system some how?

LTR isn't popular (here) so can't say as I've ever monitored an LTR system as an LTR system, but rather just listening to each frequency conventionally. What is the advantage to listening as a system? I have an SDS100 ... can an LTR system be programmed, or is there no advantage?

 

[cg]

Not sure exactly how SDRTrunk treats plain LTR. Passport variation had to have each channel entered.
LTR does not transmit any channel/frequency information. You need to find a list of frequencies used and the channel number assigned to each.
Not sure about the SDS200 and LTR. The 996 series of Unidens had Control Channel only which could be used to find LTR info.

chris

 

[rkillins]

I appreciate your insight Chris, thank you. More of a curiosity than anything. For what it's worth, I'm doing ok just listening to the frequencies conventionally.