Account  |  Mobile  |  Help    
 
Home Database Live Audio Forums Wiki Classifieds Submit Info About

Go Back   The RadioReference.com Forums > Commercial and Professional Radio > System Administration and Maintenance


System Administration and Maintenance Here is where radio system managers can discuss some of the more intricate details of managing their complex radio systems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 07-08-2002, 04:57 PM
Member
   
Join Date: May 2001
Posts: 286
Default 800 MHz. and the Interference Issue

I have heard alot of dissgusion about interference on 800. as well as the shift to 700 MHz. I read an article addressing this Nasty Problem. I'd like to share some of this if I might. The article is in the July edition of Radio Resource Magazine. and there are several large organization who propose sulations. APCO being one of them.

"Currently in the hand's of the FCC are more than 200 letters Drafted by parties in some way affected by Interference in the 800 MHz. band.Some letter's simply advise the FCC To approach the topic with utmost care: Yes, we need to allieviate the problem of interference to public safety Communications, But at what cost to business, Indusrty and the Public.

Some letter's praise a soulution that work's in a companies favor; others decry a proposed s solutions that could potentially ruin companies. Still other letters serve as formal recomendations to a course of action That could solve the Interference problem-but these recomendations would radiclly reshape spectrum in the 700, 800 and 900 MHz. Bands.

The onslaught of letters and recomendations follows a proposal Nextel Made last fall to allieviate interference to public safety communications. In short the proposal creates two contiguous blocks of spectrum in the 800 MHz. band-one for public safety, the other for digital SMR. Yet in the solution lies the problem: those licenses already in place at 800 MHz, namely industrial/land Transportation operators would need to move to the 700 and 900 MHz. bands. A consertive estimate tag's the cost of moving just the public safety entities at $2.5 billion. And who is going to pay for that? Nextel's commitment of $500 million for rebanding is laughable to some in the private radio community.

The criticism doesen't stop there, 'under it's plan, Nextel would recieve 10 megahertz of highly valuable nationwide, contiguous spectrum at 2020-2025 MHz. and 2170-2175 MHz. with out having to bid or otherwise compete for it, and with out other parties even having the oppurtunity to apply' say's Mike Rosenthal director of regulatory affairs for southern linc.

And there are other solutions. one of the most notable is singuler wireless' proposal which has the support of other wireless companies including, Alltel Corp. Technical studies conducted by Cingular indicate that by simply rebanding 800 MHz. will have virtualy no affect on interference, since the public safety readio filters will still allow all transmission within the 800 MHz.band to pass. according to Andrew Clegg, senior manager of RF strategy for Cingular Wireless.

The only way to virtully eliminate Interference problems is to completely relocate Public Safety to the Upper 700 MHz. spectrum say's Clegg, the move could be paid for by auctioning the 800 MHz. spectrum That would be vacated by Public Safety. key to this proposal. Clegg reminds us, is enforcement by the FCC and Congress of the mandate requiring broadcasters to vacate channels 60 thru 69 by the already-established 2006 deadling.

In it's defense, Nextel says interference problem lies in the origonal allocation of the spectrum. 'It's not just Nextel That's contrubiting to the Interference' says Nextel spokeperson Leigh Horner. 'The cellular providers are contributing aswell and it's going to continue untill we take a comprehensive look at rebanding 800 MHz. spectrum.'

Despite the criticism the proposal recieved, Nextel stands by it's origional plan. 'we believe we have the strongest proposal out there,' Horner say's. At the same time, Horner points out that Nextel Understands the disruption that it's proposal would cause private operators and Public Safety organizations, and say's the carrier is maintaining open lines of communication to find the best way of rebanding.

Who has the best solution?

The next three pahes list those who have Good and Not so Good proposals, and state their reaction's about Nextel's Plan's. and I really don't want to key it all In, But will show you who Responded, (ITA, Industrial Telecommunication Assn. AIRINC, APCO, UTC, AMTA and a few other's.

But it still seem's like Nextel is screwing people, and even almost sabatoging some network's intentionally, if you don't use our service, we'll interfear with your radio's till you do. My question is, Has Nextel become almost a monoply. for all Public Safety to Have to move to 700 MHz. and just after recently completeling their trip to 800. will start utter war. and leave many screwed. I under stand Now why Ft. Worth and Arlington (TX) are considedring this, and One guess as to who is helping their funding. The dealer's have lied to the Public and LE for so long, convincing them which is the way to go. But it is an interesting topic.

Radio Resource Magazine website is: www.radioresourcemag.com

In this Month's issue, also is the Public Safety Report, highliting Tetra Technology, and some really good and really technical Info about Tetra and that type of Digital Protocal and other's who Might be using Tetra Technology in the future.

Have fun
__________________
Stephen Mc Clure
Blue Ridge, Texas
*Icom Rock's*
Reply With Quote
Sponsored links
  #2 (permalink)  
Old 07-09-2002, 06:23 PM
Member
   
Join Date: May 2001
Posts: 286
Default APCO's Response

I just instaled DSL so this might be a good time to try it out, Here was The response of: Association of Public Safety Communications Officials International (APCO) It is very interesting.

"APCO's initial comments set fourth basic principals that must be considered when evaluating any plan that addresses the 800 MHz. interference problem. Plans should be evaluated based upon the reduction in interference, whether the plan includes a mechanism to reimburse all of the costs incured by public safety licensees when implementint the plan, and whether the plan will address Public Safety spectrum requirements in the 800 MHz. band.

APCO believes that while case-by-case interference remedies are important, long term solutions will require change to the currant 800 MHz. band allocations. The underlying factors creating the potential for interference need to be elimated.

Befor the interference occurs and actually threatens The safety of life and property. Fixing problems once they occur is neccessary-But not sufficient.

The need to reconfigure the 800 MHz. band also provides an oppurtunity to address serious, unmet public safety spectrum requirements. while additional spectrum has been allocated for public safety since 1996, the spectrum is either blocked by television broadcast operations in metropolitan areas where it is needed most (i.e., the 700 MHz. band) or it is necessarily limited to broadband orrelitivly short distance data transmissions (i.e., 4.9 GHz).

The events of Sept. 11 have also increased demand for public safety spectrum, which is needed to provide additional capacity and to implement new communication tools for Police, Fire, EMS and other Public Safety personal. Additional 800 MHz. spectrum is also critical for the devolopment of new and expanded interoperable, multiagency Radio communication systems.

The Nextel Proposal would modify the 800 MHz. in a manor that substantially reduces the potential for interference, and it lays the foundation for more complete elimination of interference problems associated with future improvements in equipment and system design. But while the Nextel plan also attempts to address the signiificant cost that public safety licensees would incure, it falls well below what will be neccessary.

APCO acknowledges The Nextel plan yeilds a significant amount of additional public safety spectrum; however, the Nextel Plan would displace many non-public safety licensees. The FCC would need to consider alternatives to address the requirements of those licensees to the extent possibile.

APCO will address other proposals in its reply comments, including suggestions that the 800 MHz public safety licensees move to the expanded 700 MHz band. Assuming that such a result would be benificial, accomplishing it would involve major legislation requiring television broadcasters to clear the band by a date certain in order to adjust the federal budget to account for lost auction revenue and to appropriate billions of dollars to cover the cost of moving existing public safety systems to the 700 MHz band. Whether such ligislation is attainable is, at best, uncertain.

Any shift to 700 NHz would also have to address the Canadian television allocation on channels 60 thru 69, which prevent the use of 700 MHz in signifficant portions of the states that border Canada."


That kind of answers alot for me, Personally. Arlington and Ft. Worth might plan to Move to 700, but it will not be soon, and The evergoing interference Issues with and from Nextel will wage for a while too. and That Nextel's real solution for all of this is to Clear out 800 MHz, and Move everyone out of it's way is Nazi in My opinion. Any ways Ya'all. I just liked the artical and The responses, and thought It This would be the best Place to post it. Of every where I go on the inter-net, This seem's to be the Best Place to disguss this issue. Enjoy!
__________________
Stephen Mc Clure
Blue Ridge, Texas
*Icom Rock's*
Reply With Quote
  #3 (permalink)  
Old 06-16-2003, 09:29 PM
Member
   
Join Date: May 2003
Location: Lake County, OH
Posts: 11
Default

Guess we can start calling them nazitel. Hehe.
Reply With Quote
  #4 (permalink)  
Old 06-18-2003, 11:16 AM
Banned From Posting
   
Join Date: Sep 2002
Posts: 757
Send a message via AIM to nmfire10
Default

As much as I think NexTel is a bunch of money-mongering idiots that don't give crap about anything but themselves.....

The ones who are really at fault here are the individuals who ALLOWED this get to the point it is at. The FCC allowed it to get to this point. Now we have two things.

1. Well established & publicly funded public safety radio systems that cost thousands, hundreds of thousands, or millions of dollars each.

2. A well established SMR (NexHell) with billions in assets sunk in thier system.


You can't just tell either one of them to cease and decist. They both got their spectrum legally and are probably operating within all approved specs.

Someone has to move. It blows. It is going to cost someone a ton of money. If NexTel wants to pay-off public safety to move to another bad, that is fine. But no public dafety agency should have to spend a DIME to fix a problem that someone else caused. 500 million is not a drop in the bucket and they are on crack if they seriously think that is enough.
Reply With Quote
  #5 (permalink)  
Old 06-18-2003, 11:23 AM
crayon's Avatar
RF Cartography Ninja
 
Database Admin
 
Join Date: Oct 2002
Location: 95° 53 17.67
Posts: 3,095
Send a message via ICQ to crayon Send a message via MSN to crayon Send a message via Yahoo to crayon
Default

Quote:
As much as I think NexTel is a bunch of money-mongering idiots that don't give crap about anything but themselves
They cannot spend any money to fix the problem but, by God we now get NASCAR Nextel 500.
Reply With Quote
Sponsored links
  #6 (permalink)  
Old 01-04-2004, 09:21 AM
Member
   
Join Date: Mar 2002
Location: New Orleans
Posts: 647
Default

I have been involved with radio systems for better than 35 years now. The FCC has always stood it's ground on interference issues until Nextel came around. The FCC stand always use to be the last person in that caused the problem, fixed the problem. This is basically what the rules and regulations state.

Now we see a wavering on just how the rules are enforced by the FCC. It must be nice to have money and get the government to bow down and go the way you push them. Between Motorola that makes the IDEN equipment that Nextel uses and the visits from Nextel, the FCC has been flim flamed.

Why should public safety spend money to solve a problem they didn't create? Why doesn't anybody say move Nextel instead? Let the creator of the interference solve the problem.

Jim
Reply With Quote
  #7 (permalink)  
Old 01-04-2004, 04:39 PM
Member
 
Premium Subscriber
 
Join Date: Feb 2001
Location: Greenville, SC
Posts: 1,652
Default

I'm retired but manage a mini-storage warehouse. Had trouble with electronic keypads. Gate controller would shut down at random. Had to be re-booted. Watched video tapes. Cell phone users were holding cell phone in right hand and punching in code to keypad with left hand. Once I got trapped inside property with two [2] customers. Put sign on entrance keypad. Warning-turn off Nextels and cell phones before touching any keypad. Placed same sign on outside of office. Have PRO-2067 and two other scanners in office. The 2067 got screwed up twice and had to reprogram. 800MHz digital will confuse other digital system. Larry
Reply With Quote
  #8 (permalink)  
Old 01-04-2004, 05:26 PM
Member
   
Join Date: Mar 2002
Location: Wyandotte Michigan
Posts: 625
Send a message via AIM to Josh Send a message via Yahoo to Josh
Default

Nextel messes up EVERYTHING- I've got a boost-mobile phone that I bought just to mess with until it expires (and NO, I don't plan to renew, it's an awful lousy service)

At any rate, it messes with the speakers in my car, the TV set,

when I'm listening to my ASTRO XTS3000, it causes that to be distorted and useless.

I don't know why the cops have Nextel, when using one within 5' of any other 800Mhz radio will make it a useless paperweight. Unfortunately, it doesn't seem to work the other way around.

-Josh

I use Verizon PTT! It's better.
Reply With Quote
  #9 (permalink)  
Old 01-09-2004, 05:30 PM
PJH's Avatar
PJH PJH is offline
The SystemKey Master
 
Database Admin
 
Join Date: Aug 2002
Location: Federal Plaza, Manhattan, New York County, NY, USA, Earth
Posts: 1,109
Send a message via AIM to PJH
Default

Well...lets see.

Without reposting articles and finding my stack of engineering reports etc, I'll try to make this easy.

Nextel as a whole is not the problem. In many markets, the problem has ALWAYS been there, but now becoming more noticeable. Nextel is a two-way provider with Telco access.

Yes, Nextel is not a cellular company, just ask the FCC.

For the most part, Nextel bought out many 800 and 900 SMR companies and reused their licenses for Nextel equipment. In many, if not most cases, the same freq's at the same power levels, or close to it.

As this was occurring, a few public safety agencies started to migrate into the 800MHz area - conventional and trunking - where the SMR's have been. Had Nextel not have bought up all the SMR's, the same problem would have been there.

Nextel just happens to be a scapegoat for many people. In no way am I proactively defending them, but people out there in "Scannerland" shouldn't be regurgitating falsehoods.

For those of you who don't know, this problem was widespread between cellular companies (back in the analog and early digital age), pager companies (remember those?) and wireless data services. EVERYONE was on 800MHz. Again, at the time, widespread 800MHz public safety was unheard of. Nextel is one of the few companies that STAYED in the 800MHz band. As Bell Atlantic, PacBell, Southern Lynx, Bell South etc all merged into other companies and started additional services, they moved into various parts of the RF spectrum that would support their services. This is also a reason why some phones WILL NOT work in various areas..the different proprietary technologies employed by the various cellular companies are usually NOT backwards compatible.

Now, the clicking your hear from Nextel phones are the product of the TDMA of the radio signal coming from the phone. Its an 800MHz radio. RF does things to electronics. As for the XTS, I bet if you xmit with that next to another 800 radio (or Nextel), it’s going to interfere with it. In short...Duh! Try it with two VHF or UHF radio's, I bet the same thing happens!

As I sit here in the warmth of my computer chair, talking with my friend about this topic, my Nextel is making nice clicking noises thru the computer speakers. Just for fun, I keyed up my VHF radio and guess what...my speaker BUZZED! I guess 6 watts from the Saber will do that too...strange. Hmm.

Oh well.

Personally, I think that each system problem should be dealt with on a case-by-case basis and go from there. I think both Nextel and the agency complaining should have done better research in designing their respective systems. That alone may have prevented a few problems to start with. Who ever screwed up is responsible, and should burden the costs. Just because a company can afford it, doesn't mean they should pay if the problem is/was not created by them. I am very against that thought process (i.e. taking my tax money and running it down a drain pipe for people social experiments due to bad personal decisions, but that's another topic).

I do agree that the FCC should have done a much better job, however they have done all sorts of wacky things in the last 10 years.

Ok, I am off the soapbox...

...One soapbox for sale, cheap!
Reply With Quote
Sponsored links
  #10 (permalink)  
Old 01-09-2004, 05:39 PM
Señor Member
 
Database Admin
 
Join Date: Dec 2001
Location: Texas
Posts: 3,429
Default

Hi PJ,

No thanks, brought my own soapbox!

Please check out the Nextel-1 list on yahoogroups. There you will find both factual and ancedotal evidence of Nextel's lax policy towards clean emissions when deploying new towers or expanding existing ones.

On a few rare occassions where they had bought out an existing SMR, they came to the tower site and ripped out ALL of the equipment. Problem was the SMR was co-located with other users. In some cases a local ham repeater when missing. In another a public safety repeater was erroneously decommissioned.

If you check the FCC archives you will find a relatively large number of interference complaints. For comparison, check out Southern Linc. They use the same iDEN equipment as Nextel but seem to exercise more care in engineering their sites to avoid interference.

Regards,
Rick
Reply With Quote
  #11 (permalink)  
Old 01-09-2004, 06:31 PM
PJH's Avatar
PJH PJH is offline
The SystemKey Master
 
Database Admin
 
Join Date: Aug 2002
Location: Federal Plaza, Manhattan, New York County, NY, USA, Earth
Posts: 1,109
Send a message via AIM to PJH
Default

Oh, absoulutley! I can attest that many of the install companies for Nextel were not the greatest. I found an article in one of the trade rags awhile ago how they hired "experienced" install companies to do the work, but most ended up being disgruntled employee's of the SMR they just bought out! Oops!

When the local tower company came in and installed the new cell tower at my PD, they made a few mistakes which one would think were quite stupid...and they were. The trend now from cell companies is to sell/lease back towers or to sell them outright to tower companies and lease space on them...along with that, you are seeing 3rd party compaines doing matience, which I don't believe is a good thing, but it does save them lots of $$$.
Reply With Quote
  #12 (permalink)  
Old 01-09-2004, 07:09 PM
Member
   
Join Date: Mar 2002
Location: Wyandotte Michigan
Posts: 625
Send a message via AIM to Josh Send a message via Yahoo to Josh
Default

Well, I find that my 5 watt HT1250 is capable of turning my TV set on and off (this T.V. has no remote control capability, BTW)- which is fun and fine. What I do on my single frequency is fine and dandy.

Nextel effectively jams out my XTS3000 on state police frequencies for about 1/4 mile in any direction of the tower, but NOT when I'm "inbetween sectors"- then it's just really garbled up.

Now, Public Safety TRS's tend to be on frequencies that aren't all over the band. MSP is just 866-868- and so are most other recently put up ASTRO systems.

The problem is with Nextel having and using the entire band from 851-866...with all of those repeaters running on nearly every tower spaced every couple miles that it effectively "blanket out" everything that isn't as strong (in this case, the nearest tower is probably 6 Nextel towers away- or 5 miles).

The other problem is with those damn panel antennas that shoot RF right at ya, unless you're inbetween sectors. The old SMR's used Omnis, in some places I hear Nextel does too- if Nextel used Omni-directional antennas- there'd be no problem- at least not for me. At least not here.

If you check out Nextel's answer to everyone's problem, at concensusprject.org (or something like that) they have maps of everywhere they interefere with. two counts of such interference are right near me. That's pretty unfortunate.

Who built the tower causing the intereference? I don't know, But Nextel is the only company using it, so that's who's at fault- risking other's lives through de-sense just for a few extra dollars gained by having coverage where people might not have it, but there's so many towers that your handset would have to be totally deaf not to be able to reach one.

The way I see it, Nextel's proposal is fine with me as long as Nextel is willing to fund it 100% (which they're not) otherwise, they should have access to 700 or 1900 or something like that- and migrate to it.

If Nextel doesn't fund it totally, and their proposal passes, then WE pay for it (taxpayers) and that's doesn't float well with me...who wants to pay for new equipment and programming for radios? Here in Michigan, we just gone done with state's new system, and a few years ago we paid for the downriver Mutual aid system. The department of home-land security is funding Detroit's migration to the MSP system. (They're also installing 10 new simulcast sites, which is pretty outrageous- I question whether or not it's the tall buildings that really block the coverage?)

-Josh
Reply With Quote
  #13 (permalink)  
Old 01-09-2004, 07:54 PM
Banned From Posting
   
Join Date: Sep 2002
Posts: 757
Send a message via AIM to nmfire10
Default

I have never seen anything screw with other communications equipment like a CrapTel does.
Reply With Quote
  #14 (permalink)  
Old 01-16-2004, 02:42 AM
Member
   
Join Date: Jan 2004
Location: Texas
Posts: 980
Default

Have you ever heard of the Onion? It's A parody newspaper that is funny as hell. Anyway, they have an article about a giant radio tower placed atop the earth (Reffering to RKO Pictures ads). Here is that article rewritten to be about Nextel instead of RKO.

Tower Base 2. Nome, Alaska -- In a promotional scheme criticized by many as overly ambitious and wasteful, Nextel Communications has erected a massive radio-transmitting antenna that is over a million times larger than any structure ever built by man. Rising from the Arctic Circle, the colossal tower is affixed to the earth by four support pylons mounted in Greenland, Central Canada, Central Soviet Union and an artificial island in the North Pacific specially built for this project. The full hieght is estimated at 170,000 miles, dwarfing New York's Empire State Building once the tallest man-made structure at 1,449 feet.

The wieght of the tower is estimated to be about 1/8 the wieght of the earth itself. Steel produced by 43 nations and comprising over 90% of the world's steel resources was used to build the tower. More than 70% of the world's existing buildings had to be destroyed, melted down, and incorporated into the mighty 200 mile wide supports. Astronomers are concerned of the tower's affect on the earth's orbit around the sun. "To Actually build a working radio tower, with such a powerful signal that transmissions are visible as huge lightning bolts saoring through space, could compromise the earths position in the solar system."

Since the tower's construction, no one on earth has been able to tune to any non-Nextel Broadcast, regardless of how the tuning dial is adjusted.

Just thought you'd get a kick out of that.
Reply With Quote
  #15 (permalink)  
Old 01-16-2004, 01:52 PM
dynamitedjs's Avatar
Member
   
Join Date: Dec 2003
Location: Richmond, Va. (Mechanicsville)
Posts: 396
Default NEXTEL PHONES

I had a Nextel phone once. It could turn on and off the tv, even in a hospital. I was visiting my brother and his wife (they just had a baby) and just happened to key up while the tv was on and it turned off. Everything would go click click click through speakers when they were either on or off. Being a dj I had to get rid of it because it would interfere with my dj equipment. But I never realized cops had trouble with it too until reading this thread.
Reply With Quote
Sponsored links
  #16 (permalink)  
Old 10-22-2004, 12:31 PM
Member
   
Join Date: Jun 2003
Location: Tacoma, Washington
Posts: 30
Send a message via AIM to hughwsharp
Default

It's caused a few problems here, as well, though I could never duplicate it when I needed to.

I'm not too thrilled with Nextels....
__________________
- Hugh W Sharp
Reply With Quote
Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 07:16 AM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
All information here is Copyright 2009 by RadioReference.com LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2009 by RadioReference.com LLC Privacy Policy  |  Terms and Conditions