FINDING A CONTROL CHANNEL FREQ FOR GWCC TRS

[danno145]

Recently, I found the 800 mhz trunking freqs for the Georgia World Congress Center using a FCC Database search. Programed the freqs in my pro-95 and was able to hear traffic. but cannot find a control channel. None of the freqs seem to be a control channel.... How do I find out the control freq and/or any missing freqs not listed on the FCC database..... It is a trunked system.

here are frequencies I found: 866.0875, 866.3375, 866.5875, 867.0875, 867.975, 868.925 callsign WPNZ396

 

[ericcarlson]

First, even though the system is licensed as trunked, it may not actually be trunked. Second, there are trunked system types that do not use a dedicated control channel (SmarTrunk and multiple flavors of LTR). If you hear what sounds like quick radio key-ups every few seconds, then that is a giveaway that it is an LTR system (although not all LTR systems will have this characteristic). The key-ups, if you hear them, are system idle data bursts. If it is a regular LTR system then you can track it with LTR-capable scanners once you have determined the logical channel order (LCN). Other flavors of LTR, such as Passport, cannot be tracked with any current scanners (although there are computer programs that can decode Passport data). See the LTR systems forum and this page for more information.

-Eric

 

[DanRollman]

First, even though the system is licensed as trunked, it may not actually be trunked. Second, there are trunked system types that do not use a dedicated control channel (SmarTrunk and multiple flavors of LTR). If you hear what sounds like quick radio key-ups every few seconds, then that is a giveaway that it is an LTR system (although not all LTR systems will have this characteristic). The key-ups, if you hear them, are system idle data bursts. If it is a regular LTR system then you can track it with LTR-capable scanners once you have determined the logical channel order (LCN). Other flavors of LTR, such as Passport, cannot be tracked with any current scanners (although there are computer programs that can decode Passport data). See the LTR systems forum and this page for more information.

-Eric

Indeed, Georgia World Congress Center is just such a system! LTR, with no dedicated control channel. As best I know, your Pro-95 does not follow LTR trunking systems. With few exceptions, need a Uniden scanner to do LTR.

Dan
www.AtlantaScanner.com

 

[ReceiverBeaver]

And may I ask why you want to find a control channel if there was one? That is usually something you want to avoid and ignore as it is just a bunch of hideous digital noise. Just asking. Thanks

 

[DanRollman]

And may I ask why you want to find a control channel if there was one? That is usually something you want to avoid and ignore as it is just a bunch of hideous digital noise. Just asking. Thanks

If you are monitoring a Motorola or EDACS trunked radio system with a TrunkTracker scanner, you NEED a control channel. That "hideous digital noise" is what carries the data that allows all radios, including your scanner, to properly track the conversation you are interested in.

Unlike Motorola and EDACS systems, LTR systems do not use the same type of control channel. Think of it as the "hideous digital noise" being carried in very short spurts on all frequencies, rather than one continous "hideous digital noise" on a single frequency.

Dan

 

[danno145]

GWCC LTR

Thanks for the info. By the way, I noticed that the GWCC uses Kenwood Radios. The radio display shows channels i.e. Police 12.1, Traffic 12.2 on the LCD radio display. any ideas as to what that is or means?

 

[DanRollman]

Re: GWCC LTR

Thanks for the info. By the way, I noticed that the GWCC uses Kenwood Radios. The radio display shows channels i.e. Police 12.1, Traffic 12.2 on the LCD radio display. any ideas as to what that is or means?

Those would be the talkgroups (or channels) that they have designated, and the names they have put with them. If you get an LTR scanner and can figure out the proper order for the frequencies (LTR frequencies, unfortunately, have to go in a special order to work, and you have to figure it out), you can probably find the talkgroup numbers to match those names.

Dan

 

[dhutsell]

GWCC is an LTR system