BCD436HP/BCD536HP: How to know if NXDN is trunked

[Melv7956]

Hi Using Uniden 536. We don't have a lot of NXDN in the UK but I have found a NXDN Race Track system. With DMr If I see "cap" "t3" etc I know its a trunk system, if I see DMR on screen I know its a one frequency DMR system. However, as far as I can see with NXDN there are no such indicators. Can anyone advise?

 

[trentbob]

Hi Using Uniden 536. We don't have a lot of NXDN in the UK but I have found a NXDN Race Track system. With DMr If I see "cap" "t3" etc I know its a trunk system, if I see DMR on screen I know its a one frequency DMR system. However, as far as I can see with NXDN there are no such indicators. Can anyone advise?

Put as simply as possible, if it has a number of frequencies and you are within earshot, one of the frequencies will be a control channel, I'm sure somebody will elaborate on that for you.😉

 

[wa8pyr]

Put as simply as possible, if it has a number of frequencies and you are within earshot, one of the frequencies will be a control channel, I'm sure somebody will elaborate on that for you.😉

Not completely true. NXDN Type C systems use a control channel, but Type D systems use distributed architecture where all channels can be a traffic channel (much like LTR); the next available channel sends out a data blip about every two seconds.

Best thing to do is scan all the channels associated with that system, and see if one of them is constantly busy with control channel noise, or sends a data blip every couple of seconds.

 

[trentbob]

Not completely true. NXDN Type C systems use a control channel, but Type D systems use distributed architecture where all channels can be a traffic channel (much like LTR); the next available channel sends out a data blip about every two seconds.

Best thing to do is scan all the channels associated with that system, and see if one of them is constantly busy with control channel noise, or sends a data blip every couple of seconds.

Yep I've only listened to a type-c system, as you and I both said listen to all the frequencies and see if one of them is a control channel. That's why I kept it simple. I certainly don't know about any foreign systems.

My city was a trunked 460 MHz type c system for about 5 years before it went encrypted. They finally got rid of it anyway because it didn't work very well for the police, high rate of failure and officer safety issues, city council depended on an amateur radio distributor. System never worked well.

Good luck original poster.

 

[Whiskey3JMC]

Hi Using Uniden 536. We don't have a lot of NXDN in the UK but I have found a NXDN Race Track system. With DMr If I see "cap" "t3" etc I know its a trunk system, if I see DMR on screen I know its a one frequency DMR system. However, as far as I can see with NXDN there are no such indicators. Can anyone advise?

Correct, there will be no unique indicators to separate conventional versus trunked NXDN use. You'll see NX4, NX9 or IDS either way. You'll need to monitor the other frequencies on the license (if known) for the same traffic (TGIDs, UIDs) to help determine usage. You'll come across a control channel (NX4 or NX9) or a data burst from the home channel every 2 seconds (IDAS) and these are usually indicators of trunked use

 

[INDY72]

Do European regulators have a public DB and if so, is there a set of indicators on licenses to show trunking, like with the FCC here in the USA?

 

[gary123]

Europe is almost as bad as Canada for accurate public information. My European associates say the best way is to either CC the location or use a sdr to spectrum sweep the area. I am not sure if Europe has any standard frequency jumps. IE Canada likes 100Khz (420.1125, 420.2125, 420.3125) If so you can try the next jump up and down to see if you hear any activity or CC data blips.