Central Georgia Interoperable Regional Radio System question

[jacon12]

For the past year of so I've been receiving this Macon/Bibb County P25 Phase 2 system on my Uniden BCD436HP scanner fairly well. Although the scanner seems to like one spot in one room in the house and didn't like being moved around too much I did pick up the Bibb County Sherriff's dept.
Then one day about a week ago or so.... nothing. Does anyone know if there has been a change in the system? I checked the last update in the Radio Reference database and I believe it was back in 2014.
Otherwise the scanner works fine and receives all other local traffic from surrounding counties such as Houston.
Jarrell

 

[KD4YGG]

Was through Macon this past week and noticed my PSR-800 worked well on the system. However, it's set to "AUTO FILL" on the trunking tables.

I ran PRO96COM on the CGIRRS for a very brief time period and found it uses a non-standard base frequency of 854.0000 Mhz. This "could" be the issue, as Harris systems tend to be set up a bit different than other vendor's P-25 systems. I'm not familiar with the BCD436HP.

Here's a screenshot...

 

[INDY72]

Oh yeah Harris P25 IP's have the following quirks that make things interesting... ALL of them show same SysID of 00A, all freqs in each of the sites in an system are CC's, and the SiteID/Site # technique is whacked lol. WACN's differ so I am beginning to understand that the WACN is actually the SysID?

 

[RRR]

I have a nice new BCD996P2, I was planning on trying it out tomorrow on the Macon-Bibb county (CGRRN) system, do I need to program something differently?

 

[KD4YGG]

I'm thinking you need to program in the bandplan manually using
Base = 854.0000
Step = 12.5
Offset = 0

Here's the PRO96COM file for the CGIRRS system:

FileVersion:8
-TowerInfo
#This section is here for information only. With the exception
#of the Call Sign(s), This data is not Read back into the program at all.
System ID : 00A
System Name : Macon
WACN : 92589
Tower Number (Decimal): 10-10
Tower Number (Hex) : T0A0A
Tower Description : Macon
Control Capabilities : Data,Voice,Registration
Flavor : Phase 2
Call Sign(s) :
Timestamp : Sun May 3 13:04:02 2015

-Tables
#Format: Table ID,Base Freq,Spacing,Input Offset,Assumed/Confirmed,BandWidth,Slots
00,854.00000,0.01250,-45.00000,"Confirmed",0.01250,1
08,854.00000,0.01250,-45.00000,"Confirmed",0.01250,2

-Frequencies
#Format: Channel,Usage,Frequency(/Slot),Input Channel,Input Frequency(/Slot),Input Explicit(1/0),Hit Count
"00-0005","a",854.06250,"00-0005",809.06250,0,0
"00-0057","a",854.71250,"00-0057",809.71250,0,0
"00-0099","a",855.23750,"00-0099",810.23750,0,0
"00-0119","c",855.48750,"00-0119",810.48750,0,0
"00-0127","a",855.58750,"00-0127",810.58750,1,0
"00-0151","a",855.88750,"00-0151",810.88750,0,0
"00-0159","a",855.98750,"00-0159",810.98750,0,0
"00-0179","a",856.23750,"00-0179",811.23750,0,0
"00-0181","av",856.26250,"00-0181",811.26250,0,1
"00-0207","av",856.58750,"00-0207",811.58750,1,1
"00-0239","a",856.98750,"00-0239",811.98750,1,0

 

[jacon12]

This morning I picked up the scanner and turned it on, trying to figure out what was wrong. All of a sudden it came alive (two robberies in the area). I was so shocked I almost dropped it. I had not changed anything setting wise nor moved it from its customary spot in the computer room.
Thanks,
Jarrell

 

[codeplug]

Tower Info
00A is the same System Id just found on what appears to be the Shelby County, Alabama TRS
Harris System for sure.
Appears to be multiple systems now using the same System Id of 00A now in Alabama and Georgia.
AL Shelby County System TRS frequency was 152.720, WACN: 92778, different from the GA. system.
RFSS was 010, Site was 010, NAC was 00A.
The two sites may not be connected but that is strange that both of them have the same system Id of 00A
and both systems have the the same Site Id's of 010.

Is this new site showing any neighbor sites, VHF/UHF/700/800?

 

[KD4YGG]

That's the default system ID for most Harris P25 systems...

Nothing connected/no other sites showing up.

See my post a few levels up with the screenshot showing no neighbors.

 

[KD4YGG]

Oh yeah Harris P25 IP's have the following quirks that make things interesting... ALL of them show same SysID of 00A, all freqs in each of the sites in an system are CC's, and the SiteID/Site # technique is whacked lol. WACN's differ so I am beginning to understand that the WACN is actually the SysID?

Don't forget that some of the 800mhz systems are using non standard base frequencies.

 

[relicwr]

So with a BCD325P2, I have 854 and 12.5 but it's so choppy. All freqs are entered, even did a custom band plan and I can't get it stable.

 

[KD4YGG]

So with a BCD325P2, I have 854 and 12.5 but it's so choppy. All freqs are entered, even did a custom band plan and I can't get it stable.

Might try entering only the control channel being used, using attenuation, directional beam, or a negative gain antenna. These Harris P25 systems are notorious for being hard to scan.




Also, if you're trying to monitor the Macon system (not the CGIRRS system), note that it is a TDMA-X2 system as shown in PRO96 below:

FileVersion:8
-TowerInfo
#This section is here for information only. With the exception
#of the Call Sign(s), This data is not Read back into the program at all.
System ID : 1B6
System Name : Macon
WACN : BEE00
Tower Number (Decimal): 2-2
Tower Number (Hex) : T0202
Tower Description : Macon
Control Capabilities : Voice,Registration
Flavor : X2
Call Sign(s) :
Timestamp : Sat May 2 11:44:37 2015

-Tables
#Format: Table ID,Base Freq,Spacing,Input Offset,Assumed/Confirmed,BandWidth,Slots
00,851.00625,0.00625,-45.00000,"Confirmed",0.01250,1
01,762.00625,0.00625,30.00000,"Confirmed",0.01250,1
02,851.01250,0.01250,-45.00000,"Confirmed",0.01250,2
03,762.00625,0.01250,30.00000,"Confirmed",0.01250,2

-Frequencies
#Format: Channel,Usage,Frequency(/Slot),Input Channel,Input Frequency(/Slot),Input Explicit(1/0),Hit Count
"00-0625","a",854.91250,"00-0625",809.91250,0,0
"00-0637","a",854.98750,"00-0637",809.98750,0,0
"00-0673","a",855.21250,"00-0673",0.00000,1,0
"00-0877","c",856.48750,"00-0877",811.48750,1,0

 

[jacon12]

As of today I'm receiving the system pretty good as long as I keep the scanner in one certain spot in the house and don't move it around. It might as well be a base unit...
I also have a Grecom PSR-800 scanner that I recently updated to the latest software so that it could receive and decode this P25 phase 2 system. I was pleasantly surprised that it did as well as it does BUT I'd say about 60 to 70 percent is badly garbled. I think I read somewhere that this is probably a reception problem and moving it around until I find the sweet spot may be the only remedy for that. That or maybe a directional antenna. I say I'm going to give up on the newer digital systems, but I keep trying!
Jarrell

 

[KD4YGG]

As of today I'm receiving the system pretty good as long as I keep the scanner in one certain spot in the house and don't move it around. It might as well be a base unit...
I also have a Grecom PSR-800 scanner that I recently updated to the latest software so that it could receive and decode this P25 phase 2 system. I was pleasantly surprised that it did as well as it does BUT I'd say about 60 to 70 percent is badly garbled. I think I read somewhere that this is probably a reception problem and moving it around until I find the sweet spot may be the only remedy for that. That or maybe a directional antenna. I say I'm going to give up on the newer digital systems, but I keep trying!
Jarrell

Welcome to simulcast systems...

I would try a directional antenna, at least for the home location.
Try to aim at the closest tower site:
http://www.radioreference.com/apps/db/?fccCallsign=WPXX405

You might also try using the attenuator function, or even one of those small racing-type stubby antennas.

 

[jacon12]

Welcome to simulcast systems...

I would try a directional antenna, at least for the home location.
Try to aim at the closest tower site:
WPXX405 (MACON, CITY OF) FCC Callsign Details

You might also try using the attenuator function, or even one of those small racing-type stubby antennas.

Thank you for the suggestions. I should have kept my mouth shut and not bragged on it yesterday...., I jinxed it. Shortly after that post it quit again so yes... now I'm thinking Welcome to Simulcast Systems...
When you mention small racing-type antennas do you mean the rubber duck that came with it? Running the squelch down to zero and then back up to 2 or 3 seems to help for a while, but for gosh sakes don't move it!
As the world goes more and more digital and systems are changed over to simulcast I can't see how this isn't going to affect scanner mfgs. sales. But, you guys are much more experienced than I am about this so maybe it won't be the case and scanner sales will continue to be high enough to keep them at a decent price point.
Also, and this question is for anyone, what is the difference between these two systems: This one in Macon, Ga.
Central Georgia Interoperable Regional Radio System Trunking System, Various, Georgia - Scanner Frequencies
and this one in Warner Robins, Ga.
Houston County / Peach County Trunking System, Various, Georgia - Scanner Frequencies
The first one is the one I have all the problems with and the second one very little problem at all.
Thanks for the help and knowledge,
Jarrell

 

[KD4YGG]

For the stubby antenna, you want something like this:
Comet-NCG CH-32 | 2M/440 SUPER MINI ANT 1.75 - BNC CONNECTOR

Due to the nature of simulcast systems, you want something that doesn't pick up the multiple signals very good. The multiple signal paths result in the distortion/garbled voice because the scanner is having difficulty deciding which is the "best" signal. Think of it as trying to listen to one conversation in the middle of a crowd.

This type of antenna may help, and your mileage may vary.
Also try the attenuation feature - it may help.

The Houston/Peach County is a P-25 Phase I system, and it's not a LSM-type simulcast system. And it's a Motorola system.

The Harris flavor P-25 systems are notorious for being difficult to monitor.

 

[jacon12]

For the stubby antenna, you want something like this:
Comet-NCG CH-32 | 2M/440 SUPER MINI ANT 1.75 - BNC CONNECTOR

Due to the nature of simulcast systems, you want something that doesn't pick up the multiple signals very good. The multiple signal paths result in the distortion/garbled voice because the scanner is having difficulty deciding which is the "best" signal. Think of it as trying to listen to one conversation in the middle of a crowd.

This type of antenna may help, and your mileage may vary.
Also try the attenuation feature - it may help.

The Houston/Peach County is a P-25 Phase I system, and it's not a LSM-type simulcast system. And it's a Motorola system.

The Harris flavor P-25 systems are notorious for being difficult to monitor.

Thank you for all the information. I'm understanding the problem(s) a lot better.
Jarrell