Need Help Programming Trunked Systems

[OneBadUukha]

I'm having trouble programming my Uniden BCD996P2 scanner with trunked systems. I understand how trunking fundamentally works, but I have two issues. Please help if you can.

1) Difficulty Programming Select Agencies of a Communications System

Here's a P25 system I'd like to scan....

Interagency Communications Interoperability System (ICIS): Project 25 Trunking System, Los Angeles County, California - Scanner Frequencies

I don't want to scan all the agencies allocated to this system. I'd only like to scan the Verdugo Fire group. There are no associations between the sites and the talkgroups they serve. How do I know which sites, if any, I need to program in addition to the Verdugo Fire talkgroup? If I add those sites, won't I get scanner traffic from other frequencies that I don't want? Is it possible to isolate select agencies of trunked systems, or do I have to take them all?

2) Unidentified Talkgroups Appear During Scans

Consider the same scenario as the first item. This time, however, I'd like to program only the city of Glendale. In this case there exists both a Glendale site and a Glendale talkgroup, so there's no dilemma as before. Each talkgroup has an Alpha Tag and a Description making it very easy to identify.

However, once this is programmed and I start scanning, I receive occasional transmissions from talkgroup IDs that I did not program. For example, I get comms from ID:2152 out of Glendale. This ID does not exist in the Glendale talkgroups. A quick text search on the web page listed above, however, shows that this talkgroup ID is associated with San Marino. Say what?

I'm confused. I don't know which agency is actually broadcasting (PD, Fire, Dispatch, Public Works, etc.). Perhaps it's my lack of understanding of trunked systems. My experience is much better with conventional systems. I can group frequencies and more easily narrow agency and location.

Any advice you may have would be great. Thanks.

 

[jonwienke]

You need to understand some basic principles of trunked systems.

First, any talkgroup can be broadcast from any site in the system. So select sites to monitor based on whether or not you can receive them, NOT based on any assumptions of which site broadcasts a talkgroup.

Second, any talkgroup can be broadcast on any system frequency. So do not attempt to filter content by frequency.

That said, if the system is in the RR database, then it should already be in your scanner database, and programming it manually shouldn't be necessary.

Program all of the talkgroups, then lock out or avoid the ones you don't want to hear. If the scanner hears traffic from something unknown, it won't know whether you want to hear it and will play it. Keep in mind that new talkgroups may be added at any time, and you may or may not be interested in it. Also, new talkgroups should be reported to RR so they can be added to the master database.

 

[ryradio]

In regards to your second inquiry, look up "id scan" vs. "Id search" in your 996p2 manual. You have it in id search mode.

 

[ka3jjz]

There's no master database in the 996P2; you should be importing this data using one of the popular utilities for this scanner (ARC-XT, ProScan or FreeScan).

If you wish to only hear the Verdugo talkgroups, simply create a Group for those only, and assign a Group Quick Key (GQK) for it. As long as that GQK is enabled, that will work.

I would first set up with the site physically closest to you; however, I would go to our California forum and ask whether this system is set up to echo talkgroups across all sites (simulcasting) or only echo certain talkgroups at certain sites (zoning). This will help determine which site you should be using, assuming you can hear the site you need.

Mike