Saturday, October 08, 2005

 

Quick Notes



Two notes before I run to the airport for my next flight lesson...

First:

If you have an 800 Mhz Radio that is currently used with this WC Radio Cystem (proper spelling) and you press your transmit button,
911 Knows Who You Are By The Encrypted Code Sent Out.

Today someone from Fire Station 42 (Darlington) was having fun with their radio using Fire TAC 5. In doing so you tie up the system by using (abusing ) one of our TEN precious frequencies, plus you are making an ass out of yourself because 911 (and I) know who you are.

I really don't care if you use your radio for broadcasting music, reading the Bible, or just blabbering in PigLatin however I do believe your radio would be shut off within a few minutes and serious action would be taken against you. Scotty J. would come to your house and put a Mr. Yuk sticker on your forehead !

Actually I do care, however If I SAY that I don't care I fit in better with 911 Management !

Second:

I didn't make this a FLASH like in the other Blah-gs when a tower is down or having problems because it seems like no one cares anyway, however just for the HELL of it I will tell you that the tower in the EASTERN PART of WC is having problems.

This will affect POLICE in the DISTRICT 4 Area (especially Ligonier, Ligonier Township, New Florence, St. Clair Township, Bolivar and to some degree Latrobe and Derry Portables) and all the FIRE DEPARTMENTS that serve them.



That's it for the UPDATE. PLEASE read the first Blah-g that I posted today as on a scale of 1 to 10 it is an 11 !

DECODED,
K3SAM

http://800.k3sam.com - the website
news@k3sam.com - the tips and comments hot line

 

Oh My God, It's Not JUST ME !


I was going to write you a 9,000,000 word Blah-g today HOWEVER what I found just sitting on the internet for all to read just BLEW my mind ( taxpayers of Westmoreland County please note, you may or may not be responsible for repairing my blown mind - I'll have to see if it is included in our Communications Contract first or if I can get 911 to take it out of their petty cash ).

If you got the time here is the article which is written by Sandy Lerner and Leonard Bosack (thanks guys). Not a word has been changed ! If you don't have the time, please have someone else read it and tell you about it, it is that important ! The link to this article can be found at the bottom.

I would strongly suggest that everyone that reads my Blah-g read this...

+ + + + + +
800 MHz Radio Systems in the Virginia Piedmont?
Two scientists Give their Views

Background to this essay:

Cisco Systems founders Leonard Bosack and Sandy Lerner spoke with this editor last year about Fauquier County's plan to build an 800 MHz digital trunked simulcast Public Safety Radio System throughout the County.

Shortly afterward they wrote an essay, which has its web premiere below.

In it they explore the science of radio propagation and the economics and politics of pushing cellular radio coverage into rural America.

County Sheriff and Communication Board Chairman Joseph Higgs had been in the
news because of poor maintenance of his VHF low-band [39MHz] system. He repeatedly blamed any problems that arose on "tube type" technology. In fact the Sheriff's 100 watt GE transmitter was solid-state; fire-rescue's Motorola was a 330 watt tube-type.

His no-bid maintenance contract on the equipment provided no periodic, documented electronic inspections or preventive maintenance and no environmental audit. Those factors plus improper lightning-protection of equipment and poor placement of antennas were the real causes of system failures, poor performance, and poor coverage. Since the writing of the essay the radio system maintenance was put out for competitive bid; the no-bid contractor lost but the Sheriff insisted the winner be replaced after several months; the old contractor was back.

Fortunately for Fauquier citizens, the Virginia State Police moved into the transmitter building and cleaned the site. After the Fauquier Supervisors passed a resolution endorsing a new 800 MHz system the County started making improvements to the existing system. They are still incomplete.

At the time of the essay the Sheriff used only one transmitter/receiver site to dispatch for 660 square miles. When citizens called for system improvements he said it would be foolish to spend money fixing the 2- frequency low-band system; better to buy a new $4.2 million 20 frequency 800 MHz digital trunked simulcast system. It is odd that to solve the coverage problem of a 2 dispatch-frequency simplex system with no capacity problem (used at 12% of capacity) the Sheriff advocates a 10 channel trunked system in a frequency band noted for coverage problems.

Since the essay was written, coverage problems continue in the Delaware and Phoenix 800 MHz systems. Washington, D.C.'s 800 MHz fire radio system is said to suffer from 48 significant dead zones.

Other 800MHz systems around the U.S. have experienced the increasing problem of NEXTEL and cellular transmitter interference. Still the Sheriff demands his 10 channel 800 MHz trunked system. The County was issued a
license in May, 2001 for six channels in the 800 band at one site at a power level lower than needed even as part of a 4-site system. The County forgot to ask the FCC for slow-growth implementation so it has one year to obtain the rest of the licenses and get the system built and operational.

Here is the essay of Sandy Lerner and Leonard Bosack:

We are frequently asked what kind of computer to buy. Our stock answer is, "Today is never a good day to buy a computer." Any computer. Why? Because digital technology is, after thirty years, still a very rapidly evolving technology and improvements in price and performance continue at a rapid rate.

OK, everyone knows this. So, what if you wanted to buy a computer, but the salesperson said that you had to pay for it now, but wouldn't be able to use it for two years? Maybe you wouldn't ever be able to legally use it? And, in the process of purchasing the computer, the price had tripled? For the same computer? Oh, and add to this that a couple of your neighbors bought this same computer, and it sometimes doesn't work. Would you still buy the computer? And, what if you already had a computer that still did what you needed, but was getting a little cranky because you hadn't serviced or updated anything in the twenty years you'd had it. Would you tell the salesperson to take a hike and get your old computer fixed? We would.

Now, make the price tag of that new computer not $4 million as originally quoted, but $12 million. In fact, your neighbor [Delaware] had the price of their new system quadruple from $14 million to $50 million, and it still doesn't really work. Your annual maintenance costs will be more than ten times as high as your current system, $450,000 a year. Make the two-year problem the lack of FCC licenses available and no assurance that there would ever be any legal way to employ your new system. What if we told you we could fix up your old system for less than one-tenth of the interest on the money for one year? And, finally, add the fact that simple physics tells anyone who looks that the new system will never work very well in your neighborhood. Still going to buy that computer?

This is precisely the scenario that the Fauquier County Sheriff has proposed with the new 800 megahertz, Public Safety radio system. The system must be purchased this fall, but won't be delivered and installed for eighteen months. At the end of that time, as now, there may be no FCC licenses available for new systems in that radio band.

When we were asked to informally review the current proposal, two things were appallingly clear: that the proposed system will not ever work properly, or even adequately, in a wooded, hilly environment, such as Fauquier County; and secondly, that the current system is appropriate, adequate, but desperately needs competent maintenance.

What are the real issues here?

Why is the Fauquier Sheriff's Office so convinced that Fauquier County needs the new 800 MHz system for Public Safety?

The simple answer is marketing on Motorola’s part. Let's briefly review the technical history of Public Safety radio systems: In the early eighties, Motorola made a good business out of selling VHF based Public Safety radio systems. Such a good business, in fact, that there are few other players in this market today, and practically no other vendors for 800 MHz Public Safety systems. This means that Motorola has an effective monopoly in the 800 MHz marketplace. Now, Motorola can only sell so many Public Safety radio systems before everybody has one. Add to this the fact that Motorola is a huge player in cellular telephone technology.

What has happened since the early eighties? An explosion in the cell phone marketplace, of course. So, what is the cash cow for Motorola these days? You can bet it's not a few thousand Public Safety systems. It's cell phones.

What do you do if you are Motorola and you have installed all of the “old” Public Safety systems you can and you are spending all of your research and development money on 800 MHz cellular technology because that's where the money is?

Already the urban areas are pin-cushioned with cellular transmitters installed by the cellular service providers. But the rural counties which make up much of America are essentially without cellular telephone coverage because the cellular service providers either cannot get the large number of transmission facilities installed in any profitable way, and/or they are prevented from doing so because of environmental objections raised by the local populace who do not want the countryside pin-cushioned by towers. What do you do then?

Well, if you are Motorola, you fall back on your Public Safety radio customer base, telling them that the New Technology is absolutely necessary for Public Safety. Objections which were raised on environmental grounds give way immediately in the interest of Public Safety, and Public Safety system towers are put up throughout the rural areas. Unsurprisingly, it is now cost-effective to put the cellular telephone transmitters on the new towers as the tax-payers have paid for the new towers, and presto! Motorola can sell even more cellular telephones, everywhere! Were the 800 MHz Public Safety systems really necessary to promote Public Safety, or just to sell more cellular telephones?
[
Click here to view two representative Fauquier cases in which Public Safety was woven into cell tower application arguments. Click here to view a proposal floated by Fauquier Supervisor Weeks to collaborate in the deployment of the 800 MHz system along with a cell tower network.]

Our first question is, if the old VHF-based [39 and 150 MHz] systems were not good Public Safety systems, why did 75% of all U.S. public safety agencies buy them?

There are only three possible answers: all of those community officials were stupid, Motorola lied about the efficacy of the old systems, and/or Motorola is misrepresenting things now. Well, the thousands of installed Public Safety VHF systems are working, so that makes the first two guesses impossible. So the answer must be the last reason. And, if you asked the officials in Delaware and Phoenix, Arizona, who purchased the new systems, they would probably agree.

Our second question is, why isn't a new 800 MHz Public Safety system good for Fauquier if it's so good for Motorola? Well, Motorola is relying on economics, but unfortunately any new Public Safety system needs to rely on physics: the quarter-wavelength rule, to be precise. Briefly, the problem is that any radio wave is blocked by any object whose depth is greater than one-quarter of the length of the wave. For the systems which use 800 MHz waves, this means that any object of greater size than four inches will stop the waves from transmitting.

OK, so what?

Radio transmission interacts with foliage in a frequency range that's wider than one would initially expect from the quarter-wave penetration rule.

The reason is that leaves become re-radiators. Much like a drum, an object can absorb and then re-radiate energy when its perimeter is about a quarter-wavelength of the incident field. The exact size of the "drum effect" depends upon the angle that the radio wave approaches, the leaf, the conductivity of the sap, etc., making this is a complex quantitative analysis. But qualitatively, if you draw a straight line between any transmission/ receiver pair, and there are a lot of leaves or clusters of leaves that are 4 inches across or larger, there will be significant attenuation because of scattering primarily, and absorption secondarily, The current VHF system would need leaves more than 40 inches in diameter to have the same problems.

Tree trunks are simply transmission barriers.

Fauquier County is approximately 600 square miles. What is the probability that someone traveling on the ground will have some trees and leaves in between themselves and any of the towers? Pretty high.

Oh, and modern buildings framed with steel are also barriers, scatterers and attenuators to 800 MHz-spectrum transmissions. So why did anyone make 800 MHz systems in the first place? Because the FCC had massive bandwidth in that frequency range to assign, and this was necessary for massive numbers of cellular telephones.

Back to the present. Well, the new proposal would put at least five 350' towers (that's right, three hundred and fifty feet tall), on the tallest available (read that: most visible) topography:
Cobbler Mountain, Rattlesnake Mountain, and Bull Run Mountain. These sites are all pristine environmental areas without any development. Towers would necessitate clearing acres of trees from the tops of the mountains for access and guy wires. The towers would have bright blinking lights all day and all night. Yuk! But, maybe we need to do this for Public Safety.

The best way to get the scattering and attenuation problem reduced is to have a very high 'look angle." This is the angle of the path from the receiver to the transmitter tower. It is high so the signal won't be going through the foliage, unless, of course, one is down in a valley, in which case transmission from relatively high-power towers is possible, but transmission by a low power-limited transmitter, such as is necessarily used by someone holding equipment next to his head, is virtually impossible. This is called the “talk-back” problem.

The policeman on the ground can hear the tower, but the tower can’t hear The policeman. To overcome the talk-back problem, 800 MHz systems need tremendously tall towers and high sensitivity. The best solution is both high towers and a lot of them.

This is exactly what Fairfax County has found out. Their new system has eight very tall towers. However, Fairfax County is 40% smaller than Fauquier, substantially less hilly and less wooded. Prince William county's 800MHz system proposal is for eight towers, and Prince William county is half the size of Fauquier, and is again flatter with fewer trees. Does anyone who has looked at this problem believe that the future for Fauquier County is not many, many more than the five proposed very tall towers? Not really.


Doesn't Fauquier need the new technology because the old transmitter systems are very unreliable, hopelessly obsolete and unrepairable? Not.

All high-power transmission systems are composed of vacuum tubes. Vacuum tubes get people to the moon and back, are used for daily defense communications, all airport traffic control systems, and all commercial television broadcasting uses vacuum tube-based systems. How often is any television channel unavailable. All of these organizations can buy whatever they want, and they are all very serious about communications. They all need performance and reliability. They use vacuum-tubes for transmitters. Why? Solid-state systems are more sensitive to grounding, lightning, and radiation from adjacent equipment. Vacuum tubes are enormously more resistant to nearby transmitters, ground faults, and environmental damage. And, let's not forget the real reason for going solid-state: manufacturing cost. Manufacturing cost is completely unrelated to either reliability or performance.

However, solid-state transmitter technology has a few problems that the tube technology doesn't: first, there are a whole lot more parts. About a hundred times more components in a typical digital than in the old tube-type radio systems. Are the solid-state components more reliable than the tubes? Nope. And, the second issue is even more significant: tubes fail slowly over time. They drift and get noisier. They get less efficient. With minimal monitoring, it is not difficult to tell when a tube is going south, so that with the tube-type systems, a regular calibration and maintenance program will keep these systems running indefinitely.

So why does the Sheriffs Department experience so many problems with the VHF system, while other similar organizations such as the Virginia State Police are happy with theirs? The current Public Safety radio system in Fauquier County simply has not been adequately maintained.

On the other hand, solid-state components simply fail. Without warning.

Anyone who owns a personal computer knows this. And, there are 100 times more of them. Does Motorola or the single bidder service provider for the proposed new system know this as well? They must, as it costs Fauquier County $40,000 a year now for a maintenance contract for the VHF system, but the annual budget for the new 800 MHz system with five towers is $450,000. If it's so much more reliable and the technology is so much improved, why does it cost so much more to fix?

And, speaking of fixing things, why is the current Sheriff so reluctant to repair and upgrade the current system? Reading service accounts of the transmitter sites, it is extremely clear that the current repair vendor has had no oversight: transmitters are incorrectly grounded and inadequately protected from the elements, repair procedures were neither specified nor mandated, there is no tracking procedure for equipment failure or calibration, and there was no single person or entity responsible for the performance or purview of this vendor.

Why would anyone assume that this service vendor will perform better with the new equipment than the old, given the same lack of review and management?

Having worked with this type of equipment for decades, we are astonished that the current system works at all. Under similar conditions of malign neglect, a solid-state system would simply cease to function, as opposed to continuing to function, although somewhat badly. If the issue is really Public Safety right now, isn't some better service right now better than no service? [
Click here to view editor's inspection notes on the Sheriff's equipment in 1998.]

And, if the issue is really Public Safety, why isn't the current system being upgraded for the minimum interim two years before any new system would go on-line?

For about $70,000, two outlying transmitters/ receivers could be affixed to existing towers, enormously improving reception and transmission throughout the county. For considerably less than $50,000, we estimate that the current two transmitter sites could be cleaned, repaired, calibrated, and just generally restored to the original, good working, order. This doubles the capability of the old system and makes it work for less than one-tenth of the cost of the proposed new system. The only reason we can see for the reluctance of the Sheriffs office to fix the current system is that it would prove that the new system is unnecessary. Even if there were no questions about the proposed new system, common sense would dictate that the above measures be taken as, in the best case, it will be at least two years before the new system could be installed and licensed.

Requiring that the 800 MHz system be purchased in the fall of this year, for delivery in 2002, without the assurance that the FCC will ever license the system seems ill-advised by any standard. The estimated cost of the new system has doubled in the last two years, when prices for all other digital technology are falling, and it will be another eighteen months before it is delivered to Fauquier County. The experience of neighboring areas with the new 800 MHz systems is far from uniformly encouraging.

Unless everyone agrees to cut down all of the trees and level all of the mountains, the physical problems inherent in high frequency transmission systems is not likely to change.

And, the economics of “today is never a good day to buy a computer” is also not likely to change for the foreseeable future. Why is Fauquier County buying this system now? Or at all?

+ + + + + +
WHAT AN EXCELLENT ARTICLE !

I have been saying most of this all along however not nearly as well. Again, thanks Sandy and Leonard.


Have a GREAT WEEKEND !

DECODED,
K3SAM

http://800.k3sam.com - website
news@k3sam.com - tips and comments
This article can be found at: http://www.fauquiernews.com/083101issue.htm

This page is powered by Blogger. Isn't yours?