EDACS site id help needed

[c5corvette]

Looking for people who have a SIMULCAST system near them.

Specficially a simulcast system that has some remote sites too.

What I want to know is if there is any rhyme or reason to the SID numbering??? And if sites can possibly have the same SID ???

For example:

San Antonio/Bexar County EDACS ProVoice Trunking System, San Antonio, Texas - Scanner Frequencies
The San Antonio TX system seems to have sites numbered in order 1, 2, 3, 4, 5...

Montgomery Metro Communications Cooperative District Trunking System, Montgomery, Alabama - Scanner Frequencies
The Montgomery AL system sites seems to be numbered 1, 2, 3.

Spotsylvania County Trunking System, Spotsylvania, Virginia - Scanner Frequencies
The Spotsylvania VA system sites seems to be numbered 2 and 10.

I am asking becasue I recently ran across a system that has the simulcast sites numbered "22" and then there are two remote sites coming up with SID "23" - these are DEC displayed on my 396XT.

Why would there be two remote sites with the same SID - is it by design, and if so why?

Thanks in advance,

c5corvette

 

[burner50]

Looking for people who have a SIMULCAST system near them.

Specficially a simulcast system that has some remote sites too.

What I want to know is if there is any rhyme or reason to the SID numbering??? And if sites can possibly have the same SID ???

For example:

San Antonio/Bexar County EDACS ProVoice Trunking System, San Antonio, Texas - Scanner Frequencies
The San Antonio TX system seems to have sites numbered in order 1, 2, 3, 4, 5...

Montgomery Metro Communications Cooperative District Trunking System, Montgomery, Alabama - Scanner Frequencies
The Montgomery AL system sites seems to be numbered 1, 2, 3.

Spotsylvania County Trunking System, Spotsylvania, Virginia - Scanner Frequencies
The Spotsylvania VA system sites seems to be numbered 2 and 10.

I am asking becasue I recently ran across a system that has the simulcast sites numbered "22" and then there are two remote sites coming up with SID "23" - these are DEC displayed on my 396XT.

Why would there be two remote sites with the same SID - is it by design, and if so why?

Thanks in advance,

c5corvette

Many times there is a difference between the site ID that is broadcast, and the site ID that is used at radioreference.

Some large systems re-use site ID's, and for organizational purposes, that would be a nightmare for our system here, so Database Administrators may use their own site identification schemes.

One that comes to mind is : RACOM - IL, WI, MN, NE, SD, IA Trunking System, Various, Multi-State - Scanner Frequencies

They have over 100 sites spread across several states in the upper midwest, but all sites use one of 15 standardized bandplans, so many sites actually broadcast the same site ID.

 

[mitaux8030]

Another possibility are frequency shifting repeaters, used to extend coverage to an area adjacent to existing coverage. They'll 'suck in' the signal from a donor site, and 'spit it out' on a new frequency, amplified in the process. The new signal, on a new frequency, is in all other respects an identical copy of the original, including site ID.

 

[c5corvette]

Another possibility are frequency shifting repeaters, used to extend coverage to an area adjacent to existing coverage. They'll 'suck in' the signal from a donor site, and 'spit it out' on a new frequency, amplified in the process. The new signal, on a new frequency, is in all other respects an identical copy of the original, including site ID.

That might explain what I am seeing. Thanks.

 

[c5corvette]

@ burner50 - thanks for the reply here, but that brings up more questions...

Many times there is a difference between the site ID that is broadcast, and the site ID that is used at radioreference.

Why - there should not be a difference, should there? I would assume you populate the database with what ever site ID is submitted or else you number them in the order in which they are submitted. Why would there be any other numbers used at radioreference?

Some large systems re-use site ID's, and for organizational purposes, that would be a nightmare for our system here, so Database Administrators may use their own site identification schemes.

What kind of organizational purposes do systems reuse SID's? (That is my question here in this post exactly.)

One that comes to mind is : RACOM - IL, WI, MN, NE, SD, IA Trunking System, Various, Multi-State - Scanner Frequencies
They have over 100 sites spread across several states in the upper midwest, but all sites use one of 15 standardized bandplans, so many sites actually broadcast the same site ID.

I should have specified, I was looking for single geographic area public saftey EDACS systems. Multi-county and multi-state systems for corporations are not what I am looking to understand - they are way to complicated and usually very customized per region. I know we have a few like that here in Virginia (since Ericson was / is based here in Lynchburg.)

------------

And by the way, since you're a database administrator and a moderator, could you please reopen my other thread which is an entirely different question and still hasn't been answered. http://forums.radioreference.com/database-discussion-forum/200145-site-id-sid-field-database.html

Thanks,

 

[WayneH]

And by the way, since you're a database administrator and a moderator, could you please reopen my other thread which is an entirely different question and still hasn't been answered. http://forums.radioreference.com/database-discussion-forum/200145-site-id-sid-field-database.html

Opened.

 

[c5corvette]

Thank you Wayne. Now if someone who is a database admin reads it and answers that will work. Thanks again!

 

[WayneH]

I am asking becasue I recently ran across a system that has the simulcast sites numbered "22" and then there are two remote sites coming up with SID "23" - these are DEC displayed on my 396XT.

The two remotes, are their LCN assignments the same? An EDACS radio needs the SID from the site so it knows the correct LCN table to use. The radio needs a table that has the LCN and which freq it corresponds to. I cannot see two remote sites, that are not Simulcast, having the same SID and using the same freq/LCN table.

Why they number their sites that way I cannot answer.

 

[c5corvette]

The two remotes, are their LCN assignments the same? An EDACS radio needs the SID from the site so it knows the correct LCN table to use. The radio needs a table that has the LCN and which freq it corresponds to. I cannot see two remote sites, that are not Simulcast, having the same SID and using the same freq/LCN table.

Why they number their sites that way I cannot answer.

The two remote sites each have 5 unique (not shared with the other or the main simulcast system) frequencies.

I have not been able to determine the LCN order for any of the sites yet - havent had time to.

I dont know enough about EDACS to know how or why this is, thats why I am asking this question.

I know I drove from site to site and removed the antenna on my 396XT to make sure I was in the right location and seeing the SID correctly. When I was driving to the third site I expected to see the next number up for the final SID (but I was surprised to see it duplicated.)

Any thoughts are welcome!

 

[Radioman96p71]

How far apart are the sites? They could be running both of them in simulcast with the third site (22) in 'normal' operation.

I was going to say they could just be using different LCN positions for each physical site but sharing the same site number, but that doesnt make any sense because the radio wont know which site to affiliate with.

Why they number the sites the way they do is a mystery, could be because of other neighbor systems, or some kind of logical order to it. Or they were just the system admins lucky numbers at the time! Here on the RACOM system, sites 1-15 are for normal networked sites and 20-31 are for customer specific sites. I BELIEVE there is a limit of 32 system numbers in EDACS, i remember seeing that in my EDACS documention, trying to find it now!

 

[c5corvette]

How far apart are the sites? They could be running both of them in simulcast with the third site (22) in 'normal' operation.

I was going to say they could just be using different LCN positions for each physical site but sharing the same site number, but that doesnt make any sense because the radio wont know which site to affiliate with.

Why they number the sites the way they do is a mystery, could be because of other neighbor systems, or some kind of logical order to it. Or they were just the system admins lucky numbers at the time! Here on the RACOM system, sites 1-15 are for normal networked sites and 20-31 are for customer specific sites. I BELIEVE there is a limit of 32 system numbers in EDACS, i remember seeing that in my EDACS documention, trying to find it now!

Radioman:

This is a countywide public safety system. It has several 11 channel sites in simulcast throughout the county all using the SID "22"

The other two sites are in very remote locations and both 15 miles from one another - and at least 10 miles from any of the simulcast sites.

As stated before, both of the remote sites each have 5 channels (for a total of ten distinct freqs between the two remote sites and none of the remote site freqs match the 11 in the simulcast sites - so 21 system freqs.)

I appologize, I am new to all this EDACS stuff, and just trying to understand it.

Any help is appreciated.

 

[loumaag]

If I understand what you are saying the following is true:

• A system exists that has a simulcast site of several towers (using "simulcast site" defined as the same frequencies in the same LCN all broadcasting the same on each frequency simultaneously from different locations).
• This simulcast site is broadcasting a siteID of "22".
• There are also two remote sites, using different frequencies from the main simulcast one.
• These two remote sites do not share frequencies, nor LCN lineup with each other.
• Each of these two remote sites are broadcasting siteID 22 also.

If the above describes this accurately, then one solution I can think of is that each of the remote sites and the main simulcast site do not share the same network ID, otherwise the subscriber radios would not be able to find the correct LCN to utilize.

The only other solution that I can think of is that the sites all have a unique channel line up. As I read this I guess I need to explain; that is, the system only has one each LCN1, LCN2, etc. Since you did not state what LCNs were being used the following example would allow for each siteID to be the same and yet not be the same (example only):

• Simulcast site uses: LCN1, LCN3, LCN5, LCN7, LCN9, LCN11, LCN13, LCN15, LCN17, LCN19
• Remote site 1 uses:LCN2, LCN4, LCN6, LCN8, LCN10
• Remote site 2 uses:LCN12, LCN14, LCN16, LCN18, LCN20

This brings up the question, is this system in the RR DB? If so, a link to it may prove to be helpful.

 

[burner50]

@ burner50 - thanks for the reply here, but that brings up more questions...

Many times there is a difference between the site ID that is broadcast, and the site ID that is used at radioreference.

Why - there should not be a difference, should there? I would assume you populate the database with what ever site ID is submitted or else you number them in the order in which they are submitted. Why would there be any other numbers used at radioreference?

Some large systems re-use site ID's, and for organizational purposes, that would be a nightmare for our system here, so Database Administrators may use their own site identification schemes.

What kind of organizational purposes do systems reuse SID's? (That is my question here in this post exactly.)

Because every site and system needs its own identifier in our database, If you're asking why systems are assigned duplicate ID's, you would probably have to ask the person setting the system up.

One that comes to mind is : RACOM - IL, WI, MN, NE, SD, IA Trunking System, Various, Multi-State - Scanner Frequencies
They have over 100 sites spread across several states in the upper midwest, but all sites use one of 15 standardized bandplans, so many sites actually broadcast the same site ID.

I should have specified, I was looking for single geographic area public saftey EDACS systems. Multi-county and multi-state systems for corporations are not what I am looking to understand - they are way to complicated and usually very customized per region. I know we have a few like that here in Virginia (since Ericson was / is based here in Lynchburg.)

I do not see how this would be any different than a system that is specifically for use by public safety. Most talkgroups on this system ARE in fact public safety.

And by the way, since you're a database administrator and a moderator, could you please reopen my other thread which is an entirely different question and still hasn't been answered. http://forums.radioreference.com/database-discussion-forum/200145-site-id-sid-field-database.html

Thanks,

I apologize for misunderstanding. I thought you were asking the same question twice.

 

[c5corvette]

I apologize for misunderstanding. I thought you were asking the same question twice.

No problem - thanks.

 

[c5corvette]

Lou - here you go - this may help...

If I understand what you are saying the following is true:

• A system exists that has a simulcast site of several towers (using "simulcast site" defined as the same frequencies in the same LCN all broadcasting the same on each frequency simultaneously from different locations).
• This simulcast site is broadcasting a siteID of "22".
• There are also two remote sites, using different frequencies from the main simulcast one.
• These two remote sites do not share frequencies, nor LCN lineup with each other.
• Each of these two remote sites are broadcasting siteID 22 also.

What you said is close - right up until the last line... the remote sites have a different SID

Here is what is correct:

• A system exists that has a simulcast site of several towers (using "simulcast site" defined as the same frequencies in the same LCN all broadcasting the same on each frequency simultaneously from different locations).
• This simulcast site is broadcasting a siteID of "33".
• There are also two remote sites, using different frequencies from the main simulcast one.
• These two remote sites do not share frequencies, nor LCN lineup with each other.
• Each of these two remote sites are broadcasting siteID "34".

The only other solution that I can think of is that the sites all have a unique channel line up. As I read this I guess I need to explain; that is, the system only has one each LCN1, LCN2, etc. Since you did not state what LCNs were being used the following example would allow for each siteID to be the same and yet not be the same (example only):

• Simulcast site uses: LCN1, LCN3, LCN5, LCN7, LCN9, LCN11, LCN13, LCN15, LCN17, LCN19
• Remote site 1 uses:LCN2, LCN4, LCN6, LCN8, LCN10
• Remote site 2 uses:LCN12, LCN14, LCN16, LCN18, LCN20

That is part of what I am trying to figure out. No one has figured out the LCN order yet or any TGID's. (About 97% of the traffic is ProVoice - only "fire / rescue dispatch" and "ambulance to hospital" is Analog.) One time when one guy ran Unitrunker, on the main 11 channel system CC he got

And in the meantime, I was actually trying to get someone to answer another question which was would all three sites have an LCN order of their own or could they be mixed together - obviouly from this answer, though maybe not exactly correct in relation to this system or this thread, they can be mixed.

One time when one guy ran Unitrunker, on the main 11 channel system CC the info under the LCN's list data such as 1, 7, 10, 12, 14, 21 - but never saw anything higher than 21. So I am thinking that all 21 are all mixed together when it comes to LCN order ???

This brings up the question, is this system in the RR DB? If so, a link to it may prove to be helpful.

The system is in the database: http://www.radioreference.com/apps/db/?sid=5937

 

[loumaag]

Here is what is correct:

• A system exists that has a simulcast site of several towers (using "simulcast site" defined as the same frequencies in the same LCN all broadcasting the same on each frequency simultaneously from different locations).
• This simulcast site is broadcasting a siteID of "33".
• There are also two remote sites, using different frequencies from the main simulcast one.
• These two remote sites do not share frequencies, nor LCN lineup with each other.
• Each of these two remote sites are broadcasting siteID "34".

...No one has figured out the LCN order yet or any TGID's. (About 97% of the traffic is ProVoice - only "fire / rescue dispatch" and "ambulance to hospital" is Analog.)

Okay, the figuring out of the LCN order, although more difficult, is not really hampered by ProVoice use providing the method you use is not relying on a scanner alone to figure it out. All scanners, IFAIK, skip ProVoice channel assignments at the CCh level. IOW, they don't even acknowledge the channel assignment since it is a ProVoice flagged channel assignment. This does not affect eTrunker or UniTrunker, so either (does anyone still use eTrunker??) can be used to figure out the LCN.

And in the meantime, I was actually trying to get someone to answer another question which was would all three sites have an LCN order of their own or could they be mixed together - obviouly from this answer, though maybe not exactly correct in relation to this system or this thread, they can be mixed.

"Mixed", although I am sure means what ever it means in your head, leaves me wondering if we are saying the same thing. EDACS sites within the same system can (and do) share LCNs across sites; however, that is when siteIDs must be unique. IOW, no two sites #4 can have a common LCN used. Sites with the same ID can be in different locations providing they don't share any LCNs. An example would be: Site 4 could be two locations providing the LCN line ups were like this - 4a LCN1, LCN2, LCN3, LCN4, LCN5 & 4b LCN6, LCN7, LCN8, LCN9, LCN10. This can be referred to as interleaved LCN assignments.

One time when one guy ran Unitrunker, on the main 11 channel system CC the info under the LCN's list data such as 1, 7, 10, 12, 14, 21 - but never saw anything higher than 21. So I am thinking that all 21 are all mixed together when it comes to LCN order ???

Again the word "mixed" here leaves me a little confused. EDACS sites can have up to 25 radio channels (LCNs 1-25) and of course a multi-site system can can have all 25 used at each site as long as the siteIDs are different. (Remember that simulcast towers are considered one site.)

The system is in the database: Harrisonburg-Rockingham County Public Safety Trunking System, Harrisonburg, Virginia - Scanner Frequencies

I am glad that we have it and I notice that someone, assuming based on this thread, has changed the simulcast site to site# 33. It probably would be better if those sites were marked as unverified, since according to what has been said here, the LCNs have not been figured out. I would recommend that the local guys get together on the collaboration page in the wiki and start pooling information so that the DB can be brought up to speed.

 

[c5corvette]

Okay, the figuring out of the LCN order, although more difficult, is not really hampered by ProVoice use providing the method you use is not relying on a scanner alone to figure it out. All scanners, IFAIK, skip ProVoice channel assignments at the CCh level. IOW, they don't even acknowledge the channel assignment since it is a ProVoice flagged channel assignment. This does not affect eTrunker or UniTrunker, so either (does anyone still use eTrunker??) can be used to figure out the LCN.

"Mixed", although I am sure means what ever it means in your head, leaves me wondering if we are saying the same thing. EDACS sites within the same system can (and do) share LCNs across sites; however, that is when siteIDs must be unique. IOW, no two sites #4 can have a common LCN used. Sites with the same ID can be in different locations providing they don't share any LCNs. An example would be: Site 4 could be two locations providing the LCN line ups were like this - 4a LCN1, LCN2, LCN3, LCN4, LCN5 & 4b LCN6, LCN7, LCN8, LCN9, LCN10. This can be referred to as interleaved LCN assignments.

Again the word "mixed" here leaves me a little confused. EDACS sites can have up to 25 radio channels (LCNs 1-25) and of course a multi-site system can can have all 25 used at each site as long as the siteIDs are different. (Remember that simulcast towers are considered one site.)


I am glad that we have it and I notice that someone, assuming based on this thread, has changed the simulcast site to site# 33. It probably would be better if those sites were marked as unverified, since according to what has been said here, the LCNs have not been figured out. I would recommend that the local guys get together on the collaboration page in the wiki and start pooling information so that the DB can be brought up to speed.

There is at least one person in the area playing with Unitrunker and they have been watching the LCNs pop up from the SID 33 simulcast sites. To my knowledge, no one has tried to map the LCN order yet following along watching freqs become active on a convetional scanner. That is what needs to happen next and then people will be able to trunk track the analog stuff, which is the goal. Unfortunately, I personally don't have the equipment or time to travel to all the sites and map the LCN order, hopefully someone in the area can tackle this.

When watching the main 11 channel simulcast sites (SID 33) the LCN numbers in a range from 1 to 21 appeared - so my guess is the system is interleaved with the remote sites. Further, my guess is that the remote sites are able to be numbered the same (SID 34) since they are interleaved.

Thank you for the education. I think it answered a lot of questions.

If anyone has anything to add - please jump in...

 

[WayneH]

Remember that a radio first has to associate the SID with what's programmed in it. If the two remote sites are using completely different frequencies then they cannot be using the same LCN's. The only time this can happen is if one radio is programmed specifically for one of the remote sites and never roams in to the other. If it were to it would see the LCN and then go to the wrong frequency.

So without knowing the LCN's for the remote sites there still going to be some guessing. You don't even need to figure out which freqs go to which LCN's. Ultimately, the simulcast system isn't a factor in this equation.

 

[morganAL]

Again the word "mixed" here leaves me a little confused. EDACS sites can have up to 25 radio channels (LCNs 1-25) and of course a multi-site system can can have all 25 used at each site as long as the siteIDs are different. (Remember that simulcast towers are considered one site.)


I am glad that we have it and I notice that someone, assuming based on this thread, has changed the simulcast site to site# 33. It probably would be better if those sites were marked as unverified, since according to what has been said here, the LCNs have not been figured out. I would recommend that the local guys get together on the collaboration page in the wiki and start pooling information so that the DB can be brought up to speed.

EDACS Sites can have a max of 24 channels. Unless the system is EDACS IP, then Site ID 33 is invalid. Programmer won't even allow you to program the radio with a site ID of 33. The Max is 31. Since the site in question is Simulcast, it is not an EDACS IP system; EDACS IP does not support simulcast (at least that what was said in a forum at an EDACS Conference I attended). ID 33 is usually the first CEC/IMC switch (ties the sites together) in the network. Each switch can have sites 1 thru 31. The sites can be a mixture of Simulcast, Standard, or SCAT. If more sites are required then a another IMC switch is required. The two IMC switches are connected via a Stargate switch. It is essentially another IMC but has some slight hardware differences.

To me, things don't add up with these sites.

 

[loco-lee]

EDACS Sites can have a max of 24 channels. Unless the system is EDACS IP, then Site ID 33 is invalid. Programmer won't even allow you to program the radio with a site ID of 33. The Max is 31. Since the site in question is Simulcast, it is not an EDACS IP system; EDACS IP does not support simulcast (at least that what was said in a forum at an EDACS Conference I attended). ID 33 is usually the first CEC/IMC switch (ties the sites together) in the network. Each switch can have sites 1 thru 31. The sites can be a mixture of Simulcast, Standard, or SCAT. If more sites are required then a another IMC switch is required. The two IMC switches are connected via a Stargate switch. It is essentially another IMC but has some slight hardware differences.

To me, things don't add up with these sites.

The OP said he decoded the SID on a 396XT. Perhaps you are correct that SID 33 would be invalid when programming a radio, but if 33 is the CEC/IMC switch that ties the sites together perhaps the 396XT sees that? (But that wouldnt explain why the remote sides were showing up on the 396XT as numbered 34?)

I dont know EDACS that well either so I can't help. I do know the system in question, and I was there in 1995 when the board of supervisors held a meeting to approve the funding and I told them that such a proprietary system was a bad idea.

Anyway, I think that has been the theme of what the OP was posting all along - "things don't add up with these sites" - and he or she is looking for any help they can get.