Yadkin County Freq Changes

[fcfd988]

For anyone who is interested.......

On Aug 10th Yadkin county made some changes in their frequency allocations. Before then there were 3 primary repeater pairs in use:

Rx 154.040 / Tx 154.950 PL 85.4 (Fire F-1 Dispatch)

Rx 155.385 / Tx 159.405 PL 107.2 (EMS F-4 Dispatch)

Rx 154.740 / Tx 155.535 PL 151.4 (Sheriff F-1, Law Enforcement Dispatch)

For the last year Yadkin has been battling the Tait Quasi-Sync Simulcast system that was installed in 2004. It is a 3 site system with one site being on the East Bend water tank, one site on the Yadkinville water tank and the third site on a tower on the side of Swan Creek Mountian overlooking I-77 / Hwy 21 and Jonesville.

Since day one it has not worked correctly. On the Fire F-1 channel the modulation has been up and down, getting some better, but never what it should be. Although the modulation "sounds" low, you can tell that the console is over deviating most of the time because the dispatchers voice audio is clipping and the 2-tone encoding is clipping (this is really noticable on radios with full "PL" on recieve). There are multiple areas in the southern and eastern parts of the county were 2-tone paging is very, very spotty. Also in these areas the recieved signal from the system is so bad "out of phase" that it is completely unreadable at times on base station radios in the fire stations.

It does not take a rocket scientist to be able to tell the 3 transmitter sites are transmitting "out of phase" with each other. Just tune in during a long dispatch and you will be able to hear it for yourself. Lots of times it is worse in the county than outside of the county, because when listening from outside the county, you are only hearing the transmitter closest to you, not all 3.

The radio shop maintaining this system has been adjusting on it since the beginning and it still is not fixed. At one time you could tune in to any of the 3 main channels and hear them testing on a daily basis.

In recent months an elected county official who has a background in commercial 2-way radio systems has taken it upon himself to investigate and pursue the problems and try to find a solution. After some time looking into the problem a proposal came down from himself, the equipment vendor and the maintaining radio shop.

There were 3 proposals, one was to keep things exactly as they are, and be happy with it. Another was to build 2 tower sites and move the 2 that are on the water tanks to the towers. (This is needed because the water tanks to not provide for the system's required vertical seperation for the recieve and transmit antennas.) The 3rd proposal was to do away with the Sheriff F-1 freq (because they feel like it is causing interference on the other 2 channels) and move all EMS traffic over to the fire channel and move all law enforcement traffic to the EMS channel.

The elected county official made it clear that the county has NO money to further spend on this project and the only option was the 3rd proposal.

So on Aug 10th the change was made. the new freq/channel assignments are as follows:

Rx 154.040 / Tx 154.950 PL 85.4 (Fire/EMS F-1 Dispatch)

Rx 155.385 / Tx 159.405 PL 107.2 (Sheriff F-1, Law Enforcement Dispatch)

This is supposed to be the big fix-all, eleminating the so-called interference and suddenly causing the pagers to begin working properly on the fire channel. Well, guess what...........

Now all we have different is alot more traffic on one channel and the same recieve issues as before.......

Small town politics has once again caused public safety agencies to suffer and move back in 30 years of progress.

Wes

 

[LarrySC]

Did you post this on the WNC Yahoo Group ?

 

[fcfd988]

Larry, I have only posted it here.

Wes

 

[CCHLLM]

Thanx for the update, Wes. I was wondering what the solution was going to be, and now I see it's an alternative, not a solution. I've been in the communications business for over 40 years and I've NEVER seen a Tait system operate as advertised, mostly because of the lack of proper system engineering, though I'm no fan of Tait equipment to begin with. Couple that with putting an elected official, i.e., the sheriff, and his so-called "communications" director (who shoulda stuck with his day job of flippin' hamburgers) in charge of communications for the county, and you have what amounts to sending your dog out to buy a set of cookware.

 

[fcfd988]

Bruce,

Just to update you a little, the Sheriff is not the elected official mentioned above. It is a county commissioner. Although I do not believe Fire and EMS communications should be under his control, that is a totally separate issue than this one.

Also the communications director has changed, it is no longer the person you mentioned. He moved on to a more promising career in Computer Technology. The new director is/was a telecommunicator there at the sheriff's office and moved up to assume the role of director, time will tell how well he does, but so far, there have been significant improvements, in procedures, and operationally.

Wes

 

[CCHLLM]

Thanx again fer settin' me straight about Yadkin's situation. I had heard over and over that it was the sheriff and a commissioner that were the ones who bought the mess, as it was. I knew that the former director was gone, and I can tell by listening that the situation is much better than it was. I have a feeling that what really happened was a combination of poor engineering precipitated by a "that's all the money we're gonna spend" situation. I've always wondered why there's never enough money or time to do something right the first time, but when the first attempt is a disaster, there's always money and time found somehow to do it over.

Ya know, Forsyth County has always been lucky in that the comm director actually knows something about both radio gear and telecommunicating, and has the merit badges to show for it. It does make a difference when the ones making the decisions can tell a working design from a "bill of goods."

 

[fcfd988]

Very well put, I agree totally......

Wes

 

[fcfd988]

I have had the oppurtunity to speak with Mark Strickland with RCS Communiocations and I would like to take this time to edit the original post I made with this one sent to me by him in my email. I never ment to upset anyone or cause problems. I was only trying to illustrate the problems at hand. Aparrantly I have been recieving bad information. As you can read in the below 2 posts, some of the statements I made are inaccurate and deserve this correction. I would like to take this oppurtunity to publicly apoligize to Mark Strickland and RCS Communications and thank them for providing this information. Mark, I am very sorry and wish for there to be no hard feelings. Feel free to call me if you would like to talk any further. You have my numbers. I also would like to point out to everone reading this that all statements made by me are my opinions and thoughts only, not those of Ra-Tech Services or Yadkin County Communications.

Sincerely,

Wes Hutchens

 

[fcfd988]

Hi Wes,



As the Systems Technician for RCS Communications Group, and the Project Manager for this system, I found your article amusing to say the least. If you are truly interested in what the problems with the radio system are, let me enlighten you. Then, maybe the next time you decide to write an article attempting to make both myself, and RCS Communications look bad, you will have a little more information to go on than the rumors, complaints, and false statements you have written below.



For anyone who is interested.......

On Aug 10th Yadkin county made some changes in their frequency allocations. Before then there were 3 primary repeater pairs in use:

Rx 154.040 / Tx 154.950 PL 85.4 (Fire F-1 Dispatch)

Rx 155.385 / Tx 159.405 PL 107.2 (EMS F-4 Dispatch)

Rx 154.740 / Tx 155.535 PL 151.4 (Sheriff F-1, Law Enforcement Dispatch)



Now take a closer look at the frequencies.

Let's put them side by side and break them down for simplicity:



Fire TX: 154.950 Law RX: 154.740 This gives a separation of 210khz

Law TX: 155.535 EMS RX: 155.385 This gives a separation of 150khz



The system uses Sinclair Multicoupler combiners which require a minimum frequency separation of 200 khz with a vertical antenna separation of 30ft. Due to the systems being placed on water tanks, it is impossible to provide 30ft of vertical separation, therefore the minimum requirements of the multicoupler combiner could not be met causing Fire to interfere with Law, and Law to interfere with EMS. The only solution to this problem is to either eliminate the law frequency, replacing it with a new frequency, or to provide the 30ft of vertical separation required for the system to function properly. As a radio technician, you should be able to see the frequency issues here, and recognize the problem.



As only narrow band frequencies are available, replacing the frequency would require upgrading most of the law communications equipment. These frequency problems were pointed out to both the county, and the consultant at the beginning of this project, and the frequencies were provided to RCS by the consultant. We were told that we had to use them, they could not be changed.

For the last year Yadkin has been battling (Battling is the wrong word, improving is better) the Tait Quasi-Sync Simulcast system that was installed in 2004. It is a 3 site system with one site being on the East Bend water tank, one site on the Yadkinville water tank and the third site on a tower on the side of Swan Creek Mountian overlooking I-77 / Hwy 21 and Jonesville.

Since day one it has not worked correctly. This statement is not true. The system has worked within its designed parameters since day one. It just has not worked as the end users expected it to. On the Fire F-1 channel the modulation has been up and down, getting some better, but never what it should be. Define what it should be. The equipment manufacturer has tested the system on-site, 4 times and every time it has meet their required specifications. Although the modulation "sounds" low, you can tell that the console is over deviating most of the time because the dispatchers voice audio is clipping and the 2-tone encoding is clipping (this is really noticable on radios with full "PL" on recieve). Let me address this issue by saying that the levels for both voice audio, and tone audio from the console are set so that they enter the quasi-sync system at -14.2dbv which is the required level. This has been tested over and over. There was a problem with pre-emphasis on the console line cards, but that problem has been corrected and field testing shows that the modulation levels are within tolerance.

 

[fcfd988]

There are multiple areas in the southern and eastern parts of the county were 2-tone paging is very, very spotty. Also in these areas the recieved signal from the system is so bad "out of phase" that it is completely unreadable at times on base station radios in the fire stations. To properly address this issue, you would need to look at the simulcast overlap area maps. On these maps, it can clearly be seen that the system was designed to locate all overlap issues in the southeast corner of the county. These maps were generated by the manufacturer, and provided to both the county, and the consultant at the beginning of the project. This is a function of design, not implementation.

It does not take a rocket scientist to be able to tell the 3 transmitter sites are transmitting "out of phase" with each other. Just tune in during a long dispatch and you will be able to hear it for yourself. Lots of times it is worse in the county than outside of the county, because when listening from outside the county, you are only hearing the transmitter closest to you, not all 3. Apparently it does take a rocket scientist to tell that the three transmitter sites are transmitting out of phase, because beside the fact that the system is controlled by gps clocking and therefore can not drift on either frequency or pl tone frequency, the system has also been field tested 4 times by the manufacturer and has passed all phase and distortion tests according to its design parameters.

The radio shop maintaining this system has been adjusting on it since the beginning and it still is not fixed. At one time you could tune in to any of the 3 main channels and hear them testing on a daily basis. This is a true statement, however you should realize that the system passed its acceptance testing, and any and all tests performed thereafter were provided at the request of the county, in an attempt to improve the system beyond its engineered parameters, at no additional charge. As we have stated from the beginning, tweaks and alignments will not correct a built in design flaw.

In recent months an elected county official who has a background in commercial 2-way radio systems has taken it upon himself to investigate and pursue the problems and try to find a solution. After some time looking into the problem a proposal came down from himself, the equipment vendor and the maintaining radio shop.

There were 3 proposals, one was to keep things exactly as they are, and be happy with it. Another was to build 2 tower sites and move the 2 that are on the water tanks to the towers. (This is needed because the water tanks to not provide for the system's required vertical seperation for the recieve and transmit antennas.) The 3rd proposal was to do away with the Sheriff F-1 freq (because they feel like it is causing interference on the other 2 channels) and move all EMS traffic over to the fire channel and move all law enforcement traffic to the EMS channel. The elected county official made it clear that the county has NO money to further spend on this project and the only option was the 3rd proposal. This statement is not true. The following is the actual recommendation that was made to the commissioners, and was accepted. The system improvements were proposed as a three phase plan.

Phase 1 (completed) was to replace all of the console line cards with special line cards which would remove the pre-emphasis that was causing a problem with pager tone levels. The system would then be re-aligned and tested.

Phase 2 (completed) was to either replace the law frequency with an acceptable frequency that would not cause interference, which would of course be a narrow band frequency as wide band is not available, or to eliminate the law frequency altogether. The later option was chosen because it required the least amount of equipment change and cost.

Phase 3 was to correct the engineering mistakes made by the counties consulting firm. This would require taking the sites off of the water tanks and placing them on towers so that the proper vertical separation could be provided, and also the site placement would be re-engineered to provide maximum coverage with minimum overlap.

So on Aug 10th the change was made. the new freq/channel assignments are as follows:

Rx 154.040 / Tx 154.950 PL 85.4 (Fire/EMS F-1 Dispatch)

Rx 155.385 / Tx 159.405 PL 107.2 (Sheriff F-1, Law Enforcement Dispatch)

This is supposed to be the big fix-all, eleminating the so-called interference and suddenly causing the pagers to begin working properly on the fire channel. Well, guess what........... This statement is totally untrue. Phase two of the plan was not the "big fix-all." Phase two was to simply eliminate the interference issues cause by frequency separation. The only "big fix all" solution to the problems with this radio system is to correct the engineering flaws built into the system by the consulting firm.

Now all we have different is alot more traffic on one channel and the same recieve issues as before....... This statement is also untrue. What you have now is a reduction in interference caused by frequency separation, and a 5-10dBm signal strength increase in remote areas on the Fire/EMS channel.

Small town politics has once again caused public safety agencies to suffer and move back in 30 years of progress.

The problems with the radio system in your county Wes have nothing to do with small town politics. The problems come from poor engineering by a consulting firm hired by the county, and a lack of budget to implement the required improvements. This problem could be solved completely with phase three of the proposed improvement plan, but the fact of the matter is simply that the county does not have the money to do phase three at this time. As far as living with things like they are, the system was engineered, by the consultant with approval from the county, and the understanding that there would be overlap issues in the South East corner of the county. It was tested extensively by the manufacturer, the vendor, the consulting firm, and the county, and it passed all of its acceptance testing. The reason that it passed is that it performs within its stated operational parameters based on its engineering design. The engineering issues are pointed out several times, and well documented in all of the initial paperwork provided to the county based on the engineering plans provided by the consulting firm.



This so called "informative" document you have written does not help the problem, and in the long run, will only hurt the situation. RCS has gone above and beyond any reasonable expectations in attempting to improve this system which we stated from the beginning was not properly engineered. This system was accepted, and meets both the bid requirements and the proposed coverage parameters based on the system engineering specifications provided to us by the county and its consulting firm.



Now, if you have any constructive suggestions, or if you would like to look at any of the system levels, alignments, phase analysis charts, coverage maps, emails, design schematics, or if you would just like to talk to me about the system and your complaints, my contact information is given below.



Feel free to post this edited document alongside your original document so that anyone wanting the true story can read the facts and not the fiction.



Mark Strickland

Service Technician

RCS Communications Group

800 Megahertz Drive

Winston-Salem, NC 27107

800-441-9191 ext. 133

336-788-9191 (Local)

336-650-1124 (Fax)

336-918-5369 (Cellular)

336-242-5005 (Pager)

mastrick@rcscom.com

 

[KG4TAI]

Thank you for the apology Wes. Once again, I hope that the provided information helps clear up any misconceptions about what is actually going on with the radio system in Yadkin County.

Mark Strickland
mastrick@rcscom.com

 

[CCHLLM]

With all the misinformation floating around about Yadkin's system, does anyone wonder where it's coming from? EVERYTHING that I've heard has come from people who use the system. In fact, some are people whom I would consider knowledgeable on the subject.

With that said, I've repeated some of it, and for that I apologize also. My comm experience told me to filter the noise through my knowledge of the subject, and I never thought RCS was at fault because I've never thought even one person employed there was as big an idiot as they have been made out to be. I had an impression based on previous experience that RCS was in the same position as we all have been on occasion. You know the drill, submit your specs and hope for the best only to have to compromise practically everything at installation time in order to meet cutbacks and changes dictated by political infighting, turf wars, and ignorance on the parts of the ones who can sign the bottom line. When you take the caliber of the equipment concerned, the knowledge of those who are submitting the bid, and you're familiar with the terrain, then how can the system perform so badly? The answer is usually serious compromises.

Just for informational purposes, it needs to be said that none of the misinformation I heard from those supposedly in the know came from any of RCS's competition, it came from within Yadkin County. In fact, the competitors have defended RCS's position in the whole matter, but have said little else, as is good business practice. Just thought that needed to be said.