BCD996XT: out of channels!

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AE7Q

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Is there a clever trick to be able to create more than 500 channels in a trunked system? The Seattle area is by no means huge, and I'm running into the 500 channel limit per system, especially since the 996XT counts site frequencies in the 500 channel limit (or at least appears to), and the King-County system has over 100 site frequencies. Some are duplicate (eg, backup sites), but removing the few duplicates only provides minor relief.

In a conventional system it's easy; you just create another system & groups, and divvy up the channel frequencies in some meaningful way.

Also, in a trunked system, you can create a duplicate system (with the same sites), and divvy up the TGIDs the same way. You then have to (to make the split-up meaningful) set both systems to ID-scan rather than ID-search. Obviously, this duplication impacts scanning speed, and you don't see TGIDs in use that are not programmed. Ugh. Double Ugh.

While I'm on the subject, 20 groups per system is way too low, but there are easy work-arounds for that.

I hope the new BCD536HP removes these limitations. The (beta) manual didn't mention any limits, other than the size of the microSD card. With modern software techniques, that's how it should be (no limits except for total memory size), but we all know that things occasionally aren't like they should be ...
 

cherubim

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The 500 talkgroups per system limit is one of my biggest gripes about the 396XT/996XT series. I monitor a large statewide P25 system which has over 1200+ talkgroups and only my GRE PSR-600 & PSR-500 are capable of holding that many TG's in one profile. The limitation of course is that only 32 CC's can be monitored in one TSYS obkject..

The PSR-800 has no limit on the number of talkgroups and is only restricted by the size of the microSD card. I'm hoping the BCD436HP/BCD536HP has the same type of limitation.
 

GTR8000

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No, there is no way to get around the limit per-system, it's hard coded.

Sounds like the first thing you need to do is weed out all of the voice frequencies for each site, and leave only the known control channels. That'll reclaim some of those channels right off the top.

Beyond that, you're going to have to figure out which talkgroups you don't really care about listening to, since there appear to be 494 of them in the system.

I count 27 frequencies in the entire system that are flagged as control channels, which means you can program 473 talkgroups, and would need to decide which 21 talkgroups you don't care about having programmed.


As far as the limitation with newer Uniden models, the HP-1 does not have a limit and neither should the BCD436HP or BCD536HP.
 

AE7Q

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Thanks, that's a BIG HELP !!!

No, there is no way to get around the limit per-system, it's hard coded.

Sounds like the first thing you need to do is weed out all of the voice frequencies for each site, and leave only the known control channels. That'll reclaim some of those channels right off the top.

Beyond that, you're going to have to figure out which talkgroups you don't really care about listening to, since there appear to be 494 of them in the system.

I count 27 frequencies in the entire system that are flagged as control channels, which means you can program 473 talkgroups, and would need to decide which 21 talkgroups you don't care about having programmed.


As far as the limitation with newer Uniden models, the HP-1 does not have a limit and neither should the BCD436HP or BCD536HP.

Why can I delete the voice frequencies? Is that because the control channels contain that raw frequency (rather than a coded version) when assigning a frequency?

That's a BIG HELP; THANKS !!!

I only count 26 control/alt frequencies; as I noted before, some are duplicates. I assume the only reason to keep around duplicates, is for location-based filtering, is that correct?
 

GTR8000

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The XT series tracks Motorola and P25 systems in "Control Channel Only" mode, which means it only needs to have the control channel frequencies programmed, not the voice frequencies.

The control channel doesn't send a raw frequency for 800 MHz system voice channels, rather it sends the channel # which is translated into the actual frequencies by the scanner. That is where the custom bandplan comes into play.

I'm not familiar with the site layout for the Seattle-King County system, but it looks like there are a few main simulcast sites, with a few individual fill-in sites as well. You basically only need to program the sites that you actually monitor. If you drive all over the area, then it probably wouldn't hurt to have them all programmed, especially if you have a GPS connected to the scanner and use location-based scanning.
 

bwhite

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If I understand what you are attempting, I set up the same system in 2 diff banks (I hope I have the terminology right) and added the police talkgroups in one bank and the fire to the other effectively doubling what I could monitor.
 
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