Elementary Trunk Scanning Question

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chromics

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I've read and understand the concept of trunk frequencies, but I'm still confused in programming them. From what I can gather, those frequencies with P25, Motorola, or EDACS listed in the Mode column of the CSV file need to have the trunk flag turned on in the bank data. I also presume that there can be a mix of conventional and trunk frequencies within one bank.Am I on the right track? This is an excellent forum and I appreciate the help.

Chromics
 

ofd8001

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The Medina County Ohio link you posted is a conventional system, so the trunk stuff is not applicable.

The ARC 250 Pro is fairly straightfoward as far as downloading the frequencies needed to program a scanner. It's like learning to tie your shoes - difficult at first once you get the hang of it. . .

The big thing is not "overthink" the download - simply check the stuff you wish to monitor and let the program run its course to get the right stuff where it needs to be.

It kind of sounds like you are downloading a CSV file, then trying to import that CSV file into the ARC program. The easier way is to click the Internet tab on the top row of ARC and use the RR webservice. There is a sign-in window for your Radio Reference user name and password. After signing in, you can then select your state, county and the other things you are interested in downloading.

Yes you can mix conventional frequencies and one trunked system in a given bank. I don't believe you can have two or more trunked systems in the same bank, however.
 

chromics

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Thanks for the reply. I believe that learned to program conventional frequencies by the copy and paste sequence to the software. I'm struggling to formulate the question of what I don't understand.

I'm thinking that certain frequencies are members of a trunked system. When I download the CSV for the Medina County data that I referenced, there are higher frequencies with P25, Motorola, and EDAC listed in the "Mode" column. I'm thinking that these are trunked and need programmed differently.

There seems to be some fundamental that I'm missing and when it finally clicks, it will all make sense. I think that I have learned to tie my shoes, but I keep tying my left foot to my right. Thanks for the help so far. I guess my main question is how do I identify a frequency that is trunked, and when I do how do I mix it with the conventional frequencies?
 

n4yek

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I'm thinking that certain frequencies are members of a trunked system. When I download the CSV for the Medina County data that I referenced, there are higher frequencies with P25, Motorola, and EDAC listed in the "Mode" column. I'm thinking that these are trunked and need programmed differently.
If you are seeing EDACS in the mode column, then yes it needs to be programmed differently. EDACS trunk uses LCN (logical Channel Numbers) for programming purposes. If you want to be able to track a talkgroup, your frequencies need to be in a particular order. You can scan an EDACS conventionally, but you won't be able to follow the conversation if the system is a high traffic system and there might be annoying 'beeps' that get filtered out when in trunk mode

The same goes with the P25 trunk system, but with it there is always a control channel being referenced when trunking. Your scanner always looks at the control channel until there is activity. Then it changes to the voice channel.

Some use P25 on a single channel that is not trunked, you would not have any problem monitoring them.

All can be programmed in conventional mode, you just might not be able to follow what is going on when you are listening to it.
 

chromics

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Thanks Danny. I'm slowly progressing. Can you please clarify the fact that a bank can contain conventional frequencies and one trunked system. We we speak of one trunked system, does that mean one frequency that is trunked as you describe above, or several trunked frequencies using the same trunking i.e. EDACS or P25?
 

DickH

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Thanks Danny. I'm slowly progressing. Can you please clarify the fact that a bank can contain conventional frequencies and one trunked system. We we speak of one trunked system, does that mean one frequency that is trunked as you describe above, or several trunked frequencies using the same trunking i.e. EDACS or P25?
Motorola systems can have more than one system in a bank, along with conventional freqs. However, for best results the systems should be as far apart as possible (in miles), like Seattle and Portland, for example.
EDACS systems are different because the freqs. must be in specific channels (not necessarily in order) as specified by the LCN (Logical channel NUMBER). For example, the freqs. could be in channels 1, 2, 5, 7, 10, 12, etc.Thus, there can only be one EDACS system in a bank. Also, you need to have every freq. programmed, not only the control channels.
 

ofd8001

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The image below is a screenshot of a program file I have for my 796 using ARC 250. It shows a bank that contains both conventional frequencies and frequencies for a trunked system. Metrosafe is the trunked system.

Note the trunk column: Conventional frequencies are marked as Trunk Off. If the frequencies are for a trunked system, then Trunk is On. It's been a while since I've programmed my 796, so I may be wrong about this, but I think you have to have all of the trunked frequencies. (The control channel only feature may not apply to this scanner).

Being quite candid, of the 7 or so recent model Uniden scanners I have that will do trunked scanning, I really dislike the 796. It is a pain to program and an even bigger pain to get trunking stuff going. Conventional is real easy however.

I downloaded the CSV file for Medina county. Please direct me to which frequency you suspect is a trunked frequency so I can take a closer look at it.
 
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n4yek

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It's been a while since I've programmed my 796, so I may be wrong about this, but I think you have to have all of the trunked frequencies. (The control channel only feature may not apply to this scanner).
According to page 45 of the BCD796D owners manual, your scanner can do control channel only.
I don't have one of these scanners so I can't tell you anymore than that.
 

chromics

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Trunked Example

ofd8001....

I've attached a view of the bottom of the Medina, Ohio file which contains the conventional and trunked frequencies for your review. I'm going to have to digest the supplied comments, but anything you tell me would be appreciated. This is an excellent forum and my thanks to all.
 

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ofd8001

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According to page 45 of the BCD796D owners manual, your scanner can do control channel only.
I don't have one of these scanners so I can't tell you anymore than that.
Thanks - it's coming back to me. I'm thinking I had difficulty figuruing out which Plan to use, so I just entered all of the channels for a trunked system.
 

DickH

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ofd8001....

I've attached a view of the bottom of the Medina, Ohio file which contains the conventional and trunked frequencies for your review. I'm going to have to digest the supplied comments, but anything you tell me would be appreciated. This is an excellent forum and my thanks to all.
First of all, your list is too small to read.
Are you looking at the RR database? If so, Medina county does not have a trunked system.
If they are using a trunked system it must be the Ohio state MARCS system. The only site on that huge system in Medina county is site 027 with only 4 freqs., all re-banded.
You have to put in custom tables in order to track those freqs. If you put them in as conventional freqs. you will hear them, but it won't follow (track) a conversation.

6F0F 027 (1B) Medina Medina 851.85000 852.12500 852.65000a 852.90000c
 

ofd8001

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To answer your question in your first post: Yes, frequencies associated with trunked systems have to have "On" in the trunked column. (But as you read below, there is more to trunked systems than just frequencies).

From what I can determine, the CSV download you have has all frequencies in Medina county, including conventional and trunked. There appears to be five different trunked systems in Medina.

I really don't know where to begin explaining this, so if I'm rambling and disorganized, I apologize.

Copying and pasting conventional frequencies from a CSV file is a piece of cake. Simply go forth and things will work fine.

It is the exact opposite for a trunked system. All you get are the frequencies, but programming a trunked system requires much more information. You also need to have what type of system it is and the talkgroups for the system. Depending upon what type of system it is, frequencies have to be programmed in a certain order.

Then some of the trunked systems you can receive in Medina have multiple sites. Multiple site trunked systems are dfficult to program in the 796 scanner. Later model scanners (996T and later) do a lot better with multi-site trunked systems.

You would be much better off by discarding that CSV file and using the ARC import feature on your programming software. It will grab the frequencies (in correct order if necessary), the system type and the talkgroup ID numbers. However you can choose only one site because that is all the scanner can deal with effectively.

I also suggest putting each trunked system in its own bank. There is ample "room" in the scanner for doing so.

Please see the attached image:
 
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DickH

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... Depending upon what type of system it is, frequencies have to be programmed in a certain order.
That is not correct.
Motorola systems freqs. can be in any channels - they do not need to be in any order.

EDACS systems have to be in exact channels, specified by the LCN (LCN=Logical Channel NUMBER), not in order. In order means 1,2,3,4 etc. EDACS can be, for example, in channels 1, 4, 5, 8, 12, etc. The system programmer decides which channels to use.
 

ofd8001

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We're saying the same thing - some systems (Motorola) can have the frequencies programmed without regard to order and some systems (EDACS) you do have to pay attention to the channel order.
 

DickH

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We're saying the same thing - some systems (Motorola) can have the frequencies programmed without regard to order and some systems (EDACS) you do have to pay attention to the channel order.
It's channel NUMBER, not order. If someone with an EDACS system thinks the freqs. are in order, they will put them in channels 1,2,3,4, etc. and it won't work. Of course, some systems do have them in order, but not necessarily. As I said, it depends on how the programmer set up the system. In some systems, some channels must be left blank - empty.
 

chromics

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Wow. Thanks for all of the information. It's a great forum and I appreciate everyone's help and patience. I'm going to take a couple of days to assimilate it. I'll be back with more questions. I know a lot more than I did a few days ago. Thanks again.
 

ofd8001

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It's channel NUMBER, not order. If someone with an EDACS system thinks the freqs. are in order, they will put them in channels 1,2,3,4, etc. and it won't work. Of course, some systems do have them in order, but not necessarily. As I said, it depends on how the programmer set up the system. In some systems, some channels must be left blank - empty.
Fortunately when one uses the web import feature of programming software, "stuff" is imported in the appropriate place, including the system type and settings. That's why I encourage use of import feature whenever possible.
 

chromics

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ofd8001....

I've finally figured out that with the BC796D and ARC250 software, the web import feature is lame. It brings in the frequencies only. If I ask my wife if I can buy a new scanner with capable software, would you vouch for me? Until then, I'll copy and paste columns. You've been a great help on my journey and I appreciate it.
 
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