Is this how Trunking works?

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cpsTN

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In a Trunked system, you have a set of frequencies for a city, say #1, #2, #3, #4 and #5. You have all five frequencies programmed into the scanner. One day the PD could be on #1, the FD could be on #3 and the Control Channel on #4. Since the Control Channel is continuous tones, you have to lock it out or the scanner will continuously stop on it.

The next day, or even from the morning to evening, the control channel might move from #4 to #1, so you will have to lock out #1 and remove the lock on #4, because #4 might then be the PD, and the FD might be on #5 now. The services keep changing within the frequency blocks, but you can monitor all the city's services within these same frequencies. Is this a correct assessment of how Trunking works from the scanning point of view?

Charles
Smyrna, TN
 

b7spectra

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In simple terms, the computer automatically assigns the frequency to the talk group (channel) you are talking on. I've run Trunker programs on many different TRS's and I have found that, within 50 times, the computer is not randomly assigning the channels, but once I ran it for several hours, almost each frequency had the same amount of transmission as the other.
 

sjlamb

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WOW! Do I get an award for being the most wrong? :) I assumed this because I am hearing my local Police on a different frequency than I did this morning. Thank you.

Charles
Smyrna, TN
Charles... What model scanner are you using? It needs to be a "Trunk Tracking" type in order to follow the system. Furthermore, the Rutherford County Trunked Radio System was "re-banded" in September of 2009. This is critical because, depending on the type and model of scanner you are using; you're equipment may or may not be compatible with the re-banded system.
 
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cpsTN

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Well... He is right man that is no way even close as how trunking works.
I was not complaining about being wrong, I was trying to be humorous. Anyway, I was looking the way I was "seeing" things happen on the scanner. The local PD is one a different frequency than it was this morning.

Charles
Smyrna, TN
 

cpsTN

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Charles... What model scanner are you using? It needs to be a "Trunk Tracking" type in order to follow the system. Furthermore, the Rutherford County Trunked Radio System was "re-banded" in September of 2009. This is critical because, depending on the type and model of scanner you are using; you're equipment may or may not be compatible with the re-banded system.
I am using the Radio Shack PRO-164 handheld. It says it is a Triple-Trunked Scanner. Anyway, I assume it is Trunk Tracking. It monitors Motorolas Types I, II, and Hybrid as well as EDACS and LTR. Is this what is meant by Truck Tracking? I don't know if I need to set them up any certain way to "track". I am receiving the local Trunked Police and Fire.

Charles
Smyrna, TN
 
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sjlamb

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I am using the Radio Shack PRO-164 handheld. It says it is a Triple-Trunked Scanner. Anyway, I assume it is Trunk Tracking. It monitors Motorolas Types I, II, and Hybrid as well as EDACS and LTR. Is this what is meant by Truck Tracking? I don't know if I need to set them up any certain way to "track". I am receiving the local Trunked Police and Fire.

Charles
Smyrna, TN
Your Pro-164 WILL work with the re-banded Rutherford County Motorola Type II Smartzone Trunked Radio System. I have never used or programmed a Pro-164 so, all I can do is advise you to get out your reading glasses and get started on studying this: Easier to Read Pro-97/2055 Scanner Manual This manual applies to the Pro-97, Pro-2055, Pro-164, Pro-163, and GRE's PSR300 and PSR400

I can tell you that programming this radio is EXTREMELY easier with programming software and cable to hook up to the PC. Manual programming of any modern trunking scanning is a long, painful, eye gouging, finger cramping chore, to put it mildly.

You will need to program these frequencies into the scanner:

851.06250
851.40000
852.03750
852.57500
853.40000
866.06250
866.40000
867.03750
867.57500
868.40000

and then add these TALKGROUPS: http://www.radioreference.com/apps/db/?sid=699&opt=all_tg#tgs
 
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cpsTN

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Your Pro-164 WILL work with the re-banded Rutherford County Motorola Type II Smartzone Trunked Radio System. I have never used or programmed a Pro-164 so, all I can do is advise you to get out your reading glasses and get started on studying this: Easier to Read Pro-97/2055 Scanner Manual This manual applies to the Pro-97, Pro-2055, Pro-164, Pro-163, and GRE's PSR300 and PSR400

I can tell you that programming this radio is EXTREMELY easier with programming software and cable to hook up to the PC. Manual programming of any modern trunking scanning is a long, painful, eye gouging, finger cramping chore, to put it mildly.

You will need to program these frequencies into the scanner:

851.06250
851.40000
852.03750
852.57500
853.40000
866.06250
866.40000
867.03750
867.57500
868.40000

and then add these TALKGROUPS: Smyrna Public Safety Trunking System, Smyrna, Tennessee - Scanner Frequencies
Thank You. I already have the 10 Frequencies you listed programmed into the scanner. All I need to do now is the read the first link and add the Talkgroups. Pardon my ignorance, but what will adding the Talkgroups get me after I have the frequencies programmed?

Charles
Smyrna, TN
 

sjlamb

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Well.... for one thing, it allows you to assign a "label" to each TGID so that it actually will display the name of who is talking when a particular ID is being received. For example, TGID "16" is Smyrna Police Dispatch. You can program the radio so that when TGID "16" is talking, the scanner's display will actually show "Smyrna PD-Dispatch".

More importantly, you need to realize that when the scanner is in normal scanning mode (Closed Mode in your radio), it is ONLY looking for those talkgroup IDs that you have programmed into the scanner. If you haven't entered any Talkgroups; then it has nothing to find. This allows you to hear ONLY those types of services that YOU want to hear.

When the radio is scanning in "Open Mode" it will stop on ANY and ALL talkgroups that it finds on the system, whether they interest you on not. In other words, in "Open Mode" the scanning is SEARCHING for ANY activity on the system, which means you could end up listening to the local trash collectors, electric company, etc when all you really want to hear is Police, Fire and Medics.

When you study the "Easier to Read" Manual section on "Programming Trunking Systems" pay close attention to instructions for Motorola systems.... especially about how to set the "mode".
 
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N8IAA

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Thank You. I already have the 10 Frequencies you listed programmed into the scanner. All I need to do now is the read the first link and add the Talkgroups. Pardon my ignorance, but what will adding the Talkgroups get me after I have the frequencies programmed?

Charles
Smyrna, TN
The talkgroups are not programmed into the 'channel' part of the bank. They are programmed into the sub-banks. Select the bank you wish to program the TGID's into. press PROG, press TRUNK, press FUNC, you are in the ID program mode. You then enter in the TGID's, then you can alphatag them. That way you don't have to remember what TGID's go with what agency, fd, or, pd.
Larry
 

cpsTN

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The talkgroups are not programmed into the 'channel' part of the bank. They are programmed into the sub-banks. Select the bank you wish to program the TGID's into. press PROG, press TRUNK, press FUNC, you are in the ID program mode. You then enter in the TGID's, then you can alphatag them. That way you don't have to remember what TGID's go with what agency, fd, or, pd.
Larry
Thank You Steve and Larry. While I was programming the frequencies, I saw where I would have put in the TGIDs, but I didn't. I skipped that step. When I program the IDs, I assume it won't effect the frequencies I have already programmed. In the Talkgroups list, the number I need is under the heading named DEC, correct?
 
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sjlamb

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No.... unless you change or remove the freqs that you have already programmed, the TGIDs are an add-on to another level of the memory that gives the scanner additional information to let you see and hear specifically those services and agencies that you want.

The "DEC" stand for decimal format for how the TGID # is to be displayed. You can use either Dec or Hex format BUT, you need to indicate in the scanner's menu settings which one you want. See the section in the link I sent you on Setting Talkgroup IDs and how to set the TGID format. I prefer decimal format.
 
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DickH

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Thank You Steve and Larry. While I was programming the frequencies, I saw where I would have put in the TGIDs, but I didn't. I skipped that step. When I program the IDs, I assume it won't effect the frequencies I have already programmed. In the Talkgroups list, the number I need is under the heading named DEC, correct?
I don't think you really understand how trunking works. Here is a simple explanation.

Motorola Trunking:
The object of trunking is to allow many users to share a relatively few frequencies.
A trunking system is controlled by a computer. Information (data) is exchanged between the system radios and the computer on a control channel, sometimes called a data channel. It sounds like a strong buzz.
A large system can have up to 28 freqs., 4 of which may be used as control channels. The control channel may be changed once a day or as often as the programmer decides. Some scanners need only the control channels to track an entire system. Just put in the 4 Control Channels.

Each group of users (Fire, Police, etc.) is assigned TALK GROUPS. In a Motorola Type II system, the most common type, TGs are usually in 32 number steps starting with 16 and going up to 65536; 16, 48, 80 --- 4656, 4688, 4720 --- 28944, 28976, etc. System radios can have more than 100 TGs programmed into them.

Each bank contains sub-banks where you enter the Talk Group IDs you want to hear.
Each sub-bank holds 30 Talk Group IDs.
Use the Talk Group numbers in the DEC column, not in the HEX column.

How it works
When a user pushes the talk button on his radio, data is sent to the computer. The computer chooses an unused freq. and sends that data to all the radios set to the TG of the originating unit. This all happens in a fraction of a second and it happens EVERY TIME a radio is used.

EXAMPLE:
Fire Dispatch calling Engine 4 (TG 4528 on 856.7125)
Engine 4 answering Dispatch (TG 4528 on 852.2625)
Respond to 73 Elm Street (TG 4528 on 855.9625)
Engine 4 responding (TG 4528 on 851.6375)

If you have entered TG 4528 into your scanner, it will decode the control channel data and change your scanner freqs. to follow the conversation on TG 4528.
 

cpsTN

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No.... unless you change or remove the freqs that you have already programmed, the TGIDs are an add-on to another level of the memory that gives the scanner additional information to let you see and hear specifically those services and agencies that you want.

The "DEC" stand for decimal format for how the TGID # is to be displayed. You can use either Dec or Hex format BUT, you need to indicate in the scanner's menu settings which one you want. See the section in the link I sent you on Setting Talkgroup IDs and how to set the TGID format. I prefer decimal format.
OK, but I am already having trouble. The first line of the link to program says, in part, "In Manual mode select any channel in the bank containing the ID..." If I am programming the IDs, then why does it say "in the bank containing the ID"? There shouldn't be an ID there yet. Also, when I hit PROG then TRUNK on the scanner, the display says:

ID Bank 2-1 ON
Motorola TGID#00
MOT: none

I then press the UP arrow and the TGID# changes, but when I hit ENT when I reach #16 (my first ID to enter), it just beeps at me and does nothing. Am I getting ahead of myself? This is the PRO-164 scanner.

Charles
Smyrna, TN
 

cpsTN

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I don't think you really understand how trunking works. Here is a simple explanation.

Motorola Trunking:
The object of trunking is to allow many users to share a relatively few frequencies.
A trunking system is controlled by a computer. Information (data) is exchanged between the system radios and the computer on a control channel, sometimes called a data channel. It sounds like a strong buzz.
A large system can have up to 28 freqs., 4 of which may be used as control channels. The control channel may be changed once a day or as often as the programmer decides. Some scanners need only the control channels to track an entire system. Just put in the 4 Control Channels.

Each group of users (Fire, Police, etc.) is assigned TALK GROUPS. In a Motorola Type II system, the most common type, TGs are usually in 32 number steps starting with 16 and going up to 65536; 16, 48, 80 --- 4656, 4688, 4720 --- 28944, 28976, etc. System radios can have more than 100 TGs programmed into them.

Each bank contains sub-banks where you enter the Talk Group IDs you want to hear.
Each sub-bank holds 30 Talk Group IDs.
Use the Talk Group numbers in the DEC column, not in the HEX column.

How it works
When a user pushes the talk button on his radio, data is sent to the computer. The computer chooses an unused freq. and sends that data to all the radios set to the TG of the originating unit. This all happens in a fraction of a second and it happens EVERY TIME a radio is used.

EXAMPLE:
Fire Dispatch calling Engine 4 (TG 4528 on 856.7125)
Engine 4 answering Dispatch (TG 4528 on 852.2625)
Respond to 73 Elm Street (TG 4528 on 855.9625)
Engine 4 responding (TG 4528 on 851.6375)

If you have entered TG 4528 into your scanner, it will decode the control channel data and change your scanner freqs. to follow the conversation on TG 4528.
So it is like when you tell everyone using walkie talkies to all go to another channel when one channel is heavily used, so everyone is on the "same page", although the individual doesn't have to do this. The computer does it automatically.

Charles
Smyrna, TN
 

DickH

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So it is like when you tell everyone using walkie talkies to all go to another channel when one channel is heavily used, so everyone is on the "same page", although the individual doesn't have to do this. The computer does it automatically.

Charles
Smyrna, TN
That's right.
 

cpsTN

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OK. I thought I had the programming down (from reading the link you sent) and entered the first ID (16) but when I went to enter the second (48), I can't because the highest number I can enter is 29. The IDs I have from the Smyrna page, from the DEC, are: 16, 48, 80, 112, 144, 240, 336, 368, 592, 624, 720, 848 and 912. What am I doing wrong.

Charles
Smyrna, TN
 

DickH

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That's right.
After you have entered the last freq. and hit SCAN, it will start "trunking" (doing as you described). NOW you can enter the Talk Group IDs you want to hear.

There are two trunking modes, OPEN and CLOSED (see page 38-39).
OPEN lets you hear all active Talk Groups.
CLOSED lets you hear only the TGs you have entered into the sub-banks.
In the example you showed, 2-1 is sub-bank two, position one.
You can use the arrow keys to step up or down.
Start in 1-1. Enter the first TG you want using the number keys.
Hit ENTER, Hit ENTER again or the UP arrow to step to position 1-2, then enter the next TG you want, etc., etc.
 
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