BC296D: P25 help

[fpo701]

I could use some help. I seem to be missing a step or two.

My local Type 2 system is being migrated to a P25 Phase 1 system.

(old) Type 2 system: https://www.radioreference.com/apps/db/?sid=2707
(new) P25 system: https://www.radioreference.com/apps/db/?sid=7791

A few years ago, the type 2 system went through rebanding in case that is important. The migration is seeing frequencies slide over from the old system to the new one.

I set bank 1 as Type 2/P25 800. Status bit off, End Code enabled. Programmed only the one freq that is the current control channel. Did not enable control channel only, no bank plan. Digital card enabled.

I can see the radio try to switch to a voice channel, but it just moves right back to the control channel.

I suspect the problem is has something to do with switching to the correct voice frequency, but can't seem to figure out what I have missed.

Can someone help out?

Thanks!

 

[troymail]

I could use some help. I seem to be missing a step or two.

My local Type 2 system is being migrated to a P25 Phase 1 system.

(old) Type 2 system: https://www.radioreference.com/apps/db/?sid=2707
(new) P25 system: https://www.radioreference.com/apps/db/?sid=7791

A few years ago, the type 2 system went through rebanding in case that is important. The migration is seeing frequencies slide over from the old system to the new one.

This should have no impact or meaning with regard to the new system.

I set bank 1 as Type 2/P25 800. Status bit off, End Code enabled. Programmed only the one freq that is the current control channel. Did not enable control channel only, no bank plan. Digital card enabled.

I can see the radio try to switch to a voice channel, but it just moves right back to the control channel.

This to me usually indicates that the trunking tables are wrong and the radio is trying to switch to a frequency which is not valid. Because there is no activity on that frequency, the radio then immediately returns to the control channel.

Of course, it could be something else entirely.

What do you hear when you program the P25 system frequencies as conventional?

I suspect the problem is has something to do with switching to the correct voice frequency, but can't seem to figure out what I have missed.

Can someone help out?

Thanks!

It's been quiet a while since I've played with my 296 -- and it was always a bear to program. I'll might dig mine out later and see what other guidance I can offer.

 

[W8RMH]

That system has four control channels, 1 primary and 3 alternates, make sure you program them all. If you do not enable Control Channel Only you need all the system's frequencies programmed.

 

[troymail]

I set bank 1 as Type 2/P25 800. Status bit off, End Code enabled. Programmed only the one freq that is the current control channel. Did not enable control channel only, no bank plan. Digital card enabled.

Ah - I just noticed this also.... try enabling it.

 

[troymail]

Ok - I dug out my old 296 -- (blast from the past)....

I was able to program in only the active CC frequency for my local system/site and add a single (busy) talkgroup with Control Channel only set to OFF.... seems to work fine.

Page 49 of the owners manual (https://www.uniden.com/File Library/FooterNav/Product Information/Owners Manuals/BC296Dom.pdf) seems to say that the control channel only options do/could apply to P25 systems. It is an older radio so some additional manual settings like this might make a difference...

Two other considerations -

Squelch settings

ID Search vs. ID Scan​

 

[fpo701]

Thanks for the help Troy. The radio is at my Mom's, so it'll be a few days before I get over to try some things again. In the meantime, when you programmed the frequencies, what step size did you use?

 

[troymail]

Thanks for the help Troy. The radio is at my Mom's, so it'll be a few days before I get over to try some things again. In the meantime, when you programmed the frequencies, what step size did you use?

I've never messed with step size.. I could be wrong but I do not believe it matters in your scenario.

These systems have lookup tables such that when a frequency is assigned for an active talkgroup, the radio switches to the frequency that corresponds with the entry in the table.

Most P25 systems send the trunking table information in the control channel and then which frequency to use when a talkgroup becomes active. That is why typically all you need to program is the control channel frequency. However, I believe some systems use non-standard tables and/or don't have this data in the control channel.

If you're still having problems, I highly recommend programming all of the system frequencies as conventional - just to see how strong the signal(s) are and what you can or cannot hear in that mode.

As was mentioned - if the squelch isn't set to a good position, it is possible that the control channel tunes the radio to a voice frequency that ultimately isn't breaking squelch (or there is just nothing there) so the radio goes back to the control channel.

These are the "easy" things to try - there could be other more challenging issues but we'll not get into that for now.