BEE00 - system 981 - site 1.3 - NAC 983 Mid-Atlantic area

[BM82557]

Originally here - Unidentified system 0981 site 101 which has been closed.

I hadn't looked at site 1.3 lately but here is the latest channel activity -



The 950 MHz freqs are new to me. Anyone else investigating this site?

 

[dlwtrunked]

Originally here - Unidentified system 0981 site 101 which has been closed.

I hadn't looked at site 1.3 lately but here is the latest channel activity -

View attachment 76379

The 950 MHz freqs are new to me. Anyone else investigating this site?

Some of your frequencies are probably erroneous as I never saw them and do know that in poor signals DSD+ will report such.. I believe site 1 is the east side and site 3 is the west side. Reflection off nearby mountains makes it difficult to determine. Never saw a site 2 but have not checked recently (inside the mountain?). Valid frequencies that I have for site 3 are 169.4125, 169.6000, 170.1625, and 170.6000.

 

[BM82557]

That's what I was leaning towards, temporary poor reception.

 

[kj6psg]

What does the bandplan in DSDPlus.P25data look like?

 

[BM82557]

What does the bandplan in DSDPlus.P25data look like?

Network: BEE00.981 ; Federal 981 System

Bandplan #0: Base=851.00625 Offset=-45 Spacing=6.25 BW=12.5
Bandplan #1: Base=762.00625 Offset=+30 Spacing=6.25 BW=12.5
Bandplan #2: Base=851.0125 Offset=-45 Spacing=12.5 BW=12.5 Slots=2
Bandplan #3: Base=762.00625 Offset=+30 Spacing=12.5 BW=12.5 Slots=2
Bandplan #4: Base=935.0125 Offset=-39 Spacing=12.5 BW=12.5
Bandplan #5: Base=935.0125 Offset=-39 Spacing=12.5 BW=12.5 Slots=2
Bandplan #6: Base=380. Offset=+10 Spacing=6.25 BW=12.5
Bandplan #7: Base=380. Offset=+10 Spacing=12.5 BW=12.5 Slots=2
Bandplan #8: Base=406. Offset=+9 Spacing=6.25 BW=12.5
Bandplan #9: Base=406. Offset=+9 Spacing=12.5 BW=12.5 Slots=2
Bandplan #10: Base=136. Offset=+0.9 Spacing=12.5 BW=12.5
Bandplan #11: Base=136. Offset=+0.9 Spacing=12.5 BW=12.5 Slots=2
Bandplan #12: Base=150. Offset=+0.9 Spacing=12.5 BW=12.5 Slots=2
Bandplan #15: Base=136. Offset=-4.1625 Spacing=12.5 BW=12.5

 

[kj6psg]

Yeah, the 950 MHz hits are going to be false positives. The -39 MHz offset would put inputs out-of-band for transmitting radios, nor do I know of any P25 radios that can operate up above 941 MHz. 935 MHz isn't a federal band anyways. Whoever programmed the band plan just threw every band they can think of in the table.

 

[devicelab]

i think DSD+ is doing something wonky with the P25 data as my P25 systems got all screwed up thanks to DSD+ in terms of their frequencies. I ended up renaming the p25data file and that seemed to correct everything at least so far...

 

[kj6psg]

In times of poor decodes, DSDPlus occasionally gets false positives for channel events such as group calls. The biggest clue is nonsensical or nonexistent channels for call events. Other issues I have include control channel search landing on other systems and polluting my data files, but that's another issue for another thread. I haven't checked into the specifics of removing erroneous data, but I don't believe it can be done with DSDPlus running.