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420-450 MHz 50 watts power limitation.

Discussion in 'Amateur Radio News' started by WB1WMB, May 22, 2006.

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  1. WB1WMB

    WB1WMB Ham Member QRZ Page

    Certain areas of the USA are limited to a maximum transmitter power of 50 watts by "47 CFR 2.106 Footnote US7".

    While purchasing a ICOM 910H from a Florida Ham radio shop I enquired about the limitations of transmitter power in the 70 cm band and was told that there wasn't any. I was sure that there was a limitation and found the text of 47 CFR 2.106 Footnote US7 which indeed limits transmitter power in 10 specific areas of the United States. The text of the FCC rule follows:



    47 CFR 2.106 Footnote US7

    US7 In the band 420-450 MHz and within the following areas, the peak envelope power output of a transmitter employed in the amateur service shall not exceed 50 watts, unless expressly authorized by the Commission after mutual agreement, on a case-by-case basis, between the Federal Communications Commission Engineer in Charge at the applicable district office and the military area frequency coordinator at the applicable military base. For areas (e) thru (j), the appropriate military coordinator is located at Peterson AFB, CO.

    (a) Those portions of Texas and New Mexico bounded on the south by latitude 31°45' North, on the east by 104°00' West, on the north by latitude 34°30' North, and on the west by longitude 107°30' West;

    (b) The entire State of Florida including the Key West area and the areas enclosed within a 200-mile radius of Patrick Air Force Base, Florida (latitude 28°21' North, longitude 80°43' West), and within a 200-mile radius of Eglin Air Force Base, Florida (latitude 30°30' North, longitude 86°30' West);

    © The entire State of Arizona;

    (d) Those portions of California and Nevada south of latitude 37°10' North, and the areas enclosed within a 200 mile radius of the Pacific Missile Test Center, Point Mugu, California (latitude 34°09' North, longitude 119°11' West);

    (e) In the State of Massachusetts within a 160-kilometer (100 mile) radius around locations at Otis Air Force Base, Massachusetts (latitude 41°45' North, longitude 70°32' West);

    (f) In the State of California within a 240-kilometer (150 mile) radius around locations at Beale Air Force Base, California (latitude 39°08' North, longitude 121°26' West);

    (g) In the State of Alaska within a 160 kilometer (100 mile) radius of Clear, Alaska (latitude 64 degrees, 17 north, longitude 149 degrees 10 west).

    (h) In the State of North Dakota within a 160 kilometer (100 mile) radius of Concrete, North Dakota (latitude 48 degrees 43 north, longitude 97 degrees 54 west).

    (i) In the States of Alabama, Florida, Georgia and South Carolina within a 200 kilometer (124 mile) radius of Warner Robins Air Force Base, Georgia (latitude 32°38 North, longitude 83°35 West).

    (j) In the State of Texas within a 200 kilometer (124 mile) radius of Goodfellow Air Force Base, Texas (latitude 31°25 North, longitude 100°24 West).


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

    MapInfo data for Download

    US7 Footnote map data in MapInfo format
    OET -- 47 CFR 2.106 Footnote US7
     
  2. KC0W

    KC0W Premium Subscriber QRZ Page

    I have worked Florida 4 times on 432 MHz EME & Arizona 2 times. Were they running 50 or less watts?..........SURE they were. [​IMG]

    I had to take down my 432 MHz EME array due to a move last spring. Hope to have it up and running again by this fall.


    Tom kcØw
     
  3. W1YW

    W1YW Ham Member QRZ Page

    It is important to obey these restrictions, because of NTIA based communications in those areas.

    Surprised Area 51 isn't on the list ;-)
     
  4. K3UD

    K3UD Guest

    Wonder how many hams even know this. I knew it at one time but have not thought about it in years. I also remember when there were geographical power restrictions on 160 meters much like this. Has there been any enforcement actions?

    I bet Glen has all the info [​IMG]

    73
    George
    K3UD
     
  5. AA1MN

    AA1MN Ham Member QRZ Page

    The only reason that it isn't is because then the government would have to acknowledge it's existence and stir up more controversy about the Roswell UFO crash and the Moon Landing Hoaxes.

    But it doesn't stop there, my friend, oh no not by a long shot.  It delves much deeper into governmental lurid deceptions than anyone of us could even begin to imagine.

    Now, I'm not at liberty to disclose my sources for reasons of confidentiality and fear of reprisals which I'm not at this time ready to deal with but I have it on good authority and from reliable sources that former Beatle, John Lennon, is in fact being kept under close guard at Area 51 for reasons so well kept that none of his surviving bandmates are even aware of them.  Suffice it to say, Chip, that Yoko Ono orchestrated her husband's "murder" to benefit her -- and his -- own profit and for the profit of the United States government as well.

    None of us will ever know the truth about this, I'm sure, so it's be that we all just pretend that this post was never made, leave quietly and move on.  But above all, keep transmitter power levels at or below 50 watts when in the Arizona area.

    [​IMG]

    Chuck "The Truth Is Out There" AA1MN
     
  6. W5HTW

    W5HTW Ham Member QRZ Page

    It is true. Experiments were done at Area 51 as well as the even more secret Area 101. These experiments related to an alleged "youth drug" which was supplied by an alien (not Mexican) spaceship that laned secretly in downtown Burbank, one day at noon.

    Photos have been taken that show Elvis as a 17 year old, fumbling with a guitar, and standing next to a 2005 Humvee. He remarked, according to the caption, that the Humvee was like the tank he drove in Germany.

    It appears the youth drug did not simply halt aging but reversed it. The scientists at Area 101 now have to wait for Shirley McLaine to recyle yet again, so they can watch and learn the secrets of her creation, recreation, and re-recreation, as they believe, again according to an unnamed source, she inbibed a dab of this drug, or perhaps something vaguely similar, in her earlier days.
     
  7. KB4OID

    KB4OID Ham Member QRZ Page

    The power level restriction is because of the Missile Warning and Spacetrack Network. The areas in question are home to phased array radar systems used to keep track of the REAL UFO's in space, other country's satellites.

    http://www.peterson.af.mil/hqafspc....ack.htm

    Here in Northwest Florida, we have one of these radars hosted at Eglin, AFB. These systems used to be called SPADATS, but I think they changed the acronym to confuse the innocent ;) Anyway, it is possible to get an STA (Special Temporary Authorization) from the FCC to operate with higher power on 70 cm, such as for EME, but it requires that the commander of the Missile Command sign off on it. There used to be one ham near here that had an STA, and he had to call a number and let them know prior to operation. Based on my conversations with hams who were employed at the radar site, this restriction is in effect because the lower frequency limit of the radar is about 400 MHz.
    I doubt Area51 as one of these radars, as there is no 'alien' technology in them, and therefore, beneath their notice  [​IMG]
    73....~Steve>
     
  8. AA1MN

    AA1MN Ham Member QRZ Page

    Good Lord in Heaven!

    Had I ever known that Shirley McLaine was involved in this, much less her inibriation, I never would have posted to begin with ...

    Now, if you'll excuse me, I must have my home phone number changed to an unlisted number, switch license plates on my vehicle and go into hiding!

    Chuck "No Longer Out There" AA1MN
     
  9. KB7UXE

    KB7UXE Ham Member QRZ Page

    The stories you have just read are ture.
    The names have been changed to protect the innocent.

    This is Waldo Wifflhiemer signing off.
     
  10. kb3eqa

    kb3eqa Guest

    Holy Crap!

    I'm a radio and radar technician in the USAF at Robins AFB, GA and I didn't have a clue. I spoke with a few people in our club, and they were all oblivious too. I suspect our repeater committee knows, I always wondered why our 440Mhz repeater only ran at 45w.

    I guess I'll shelve my plans for a 500w 440Mhz amplifier [​IMG]

    73s de
    Dave Marshall, AB3I
     
  11. W9AFB

    W9AFB Ham Member QRZ Page

    There's an area in New Mexico right around where the first nuke tests were being done that you are not allowed to use 440. A few hours north of Holloman AFB/White Sands.
     
  12. WD8OQX

    WD8OQX Ham Member QRZ Page

    I KNEW that there were restrictions but not that they were this wide spread - don't mean to contradict but have to wonder, could the info be wrong?
     
  13. W6EM

    W6EM Ham Member QRZ Page

    More supposition, as usual.  From the usual source.

    Yes, the reason for the restriction is as was stated by someone else.  A special radar that the Air Force uses at some, but not all of its facilities.

    While a resident of FL, and a new owner of a 110W UHF mobile radio, I was informed of the limitation by a fellow ham.

    Oddly enough, though, a UHF repeater, with a gain antenna and feeding 3" gas-filled hardline with more than 100W out of its duplexer got permission to operate at its site 40 miles south of Tampa.  If that weren't enough, its antenna height was about 1100 feet above sea level!!!

    So, me, a little old mobile user thought heck, if they could get permission to do that while only 40 miles from Central Command HQ at MacDill AFB, then, so could I.

    The process was this:  I contacted the NTIA Military Area Frequency Coordinator at Patrick AFB, FL.  I included my proposed output power, estimated line loss, and estimated antenna gain.  He OK'd my operation at well above 100W ERP.  And, I took his approval to the FCC Enforcement Bureau Regional Director in Tampa, and he issued me, in effect, Special Authority (Permanent) for mobile operation in FL.

    Fairly straightforward.

    As a first step, for anyone interested, since there no longer are "Engineers-in-Charge", try contacting the FCC Regional Director of their respective areas to obtain the contact information for the correct NTIA Military Area Frequency Coordinator.

    Since I now live in Alabama, I haven't operated much at UHF and only at low power since there are so many hills here.

    On top of all this, isn't it interesting that a mobile station got authorization?  Perhaps, me thinks, the restriction may have out lived its usefulness.

    73,

    Lee
    W6EM
     
  14. K2WH

    K2WH Platinum Subscriber Platinum Subscriber Life Member QRZ Page

    I knew about this 35 years ago and never forgot it.

    K2WH
     
  15. WA9SVD

    WA9SVD Ham Member QRZ Page

    Wait! I thought it was Elvis who shot J.R., and J.F.K. slowly drove the getaway vehicle, a white Ford Bronco...

    The power limitations are in place because there are military (and even civilian) radar installations that still use the 400 MHz and above frequencies. (Not ALL radar is in the microwave region!)
    70 cm IS a shared band, and Amateur Radio has secondary status; thus, we have the restrictions, not the government stations or facilities.

    But there ARE exceptions to the rules. An "earth station" (such as one for satellite operations CAN transmit up to 611 Watts ERP, 435-438 MHz, and higher power if they get authorization, as it says, on a case by case basis. The stipulation is that the antenna would have to be pointed more that 10° above the horizon. Not too hard for a satellite antenna array.

    It is all in the rule book, and we are supposed to know and follow the rules. I'd think Riley would take a dim view of Amateurs who interfered with military radar or other government operations.

    Then again, a 50 Watt limit isn't as bad as total prohibition from use of 70 cm. in designated areas. But regardless of power level, we must NOT cause interference to other services on 70 cm, and we are NOT provided any protection from interference by the government services. THEY have the primary allocation.
     
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