BCD436HP/BCD536HP: NXDN9600 Trunk Tracking issue.

[VA3ADP]

I have been trying to monitor two separate NXDN9600 systems that are in close proximity of each other. Ive tried just about everything such as setting LCN'S to 0 even though I dont think they've changed. Ive been able to hear this system conventionally, and the system does appear to be using trunking since I have observed RSSI and system ID.

The weird part about the whole thing is that the TG's do appear for a few seconds and then dissappear. The system is not utilizing any sort of privacy. I am not sure what is exactly going on.

Some help would be great.

Thank you.

 

[Whiskey3JMC]

Two separate SYSTEMS or two separate SITES on the same system? You use "system" in the singular tense for most of the post. If the latter, perhaps simulcast distortion is a factor? Could it be full or partial encryption? Adjust the digital threshold value, I find 10 to 12 works best for NXDN systems in my area, ymmv. Run LCN finder to get correct LCNs once you've confirmed it's indeed trunked

 

[Ubbe]

Push on the silver dial for Fn and then push on the volume knob to let the display show data errors.
Too many errors will make the scanner stop decoding. 5 or lower are fine but up to 10 it will struggle.

If you have the Threshold set to manual you can turn the silver dial to change it while the Fn are shown in the display.

It also seems that NXDN9600 can use a narrow mode of 2,5KHz wide modulation that the 436/536 doesn't have filters or audio levels from the discriminator to handle properly, its on their edge of decoding. I have the same problem with some cruiser ships that use 2,5KHz level for their DMR systems and my 436 and 536 mostly ignores that digital signal and refuse to decode it. Works fine in DSD though.

/Ubbe