420-450 MHz 50 watts power limitation.

there is actually a road sign on the road in NM that runs from Carrazzoso to Socorro,NM past the Valley of Fires state park and the (closed) gate to the Red Canyon Range Camp. Sign mentions "amateur radio & 432".. or meybe 430-450.. Ed

 

as far as some of the other posts: brings to mind the famous quote; "are all fishermen liars or do all liars fish?" ... with the substitution of hams for fisherman, and "'sick" for liars.. sigh..

 

In Massachusetts, we had the 440 MHz Pave Paws radar at Otis AFB to protect. However, we could run 611 watts ERP to a satellite or other Earth Station:
97.313 Transmitter power standards.

(f) No station may transmit with a transmitter power exceeding 50 W PEP on the UHF 70 cm band from an area specified in footnote US7 to §2.106 of the FCC Rules, unless expressly authorized by the FCC after mutual agreement, on a case-by-case basis, between the EIC of the applicable field facility and the military area frequency coordinator at the applicable military base. An Earth station or telecommand station, however, may transmit on the 435-438 MHz segment with a maximum of 611 W effective radiated power (1 kW equivalent isotropically radiated power) without the authorization otherwise required. The transmitting antenna elevation angle between the lower half-power (-3 dB relative to the peak or antenna bore sight) point and the horizon must always be greater than 10°. (emphasis added)

Then there's Line A, which protects Canadian radio users, and is more or less 100 miles from the Canadian border. It appears the FCC was unsure where it is, exactly.

In any case, for part of its length, Line A runs North and South, which renders the wording in Part 97 less than perfectly clear:

§97.303 Frequency sharing requirements.
(f) In the 70 cm band:
(1) No amateur station shall transmit from north of Line A in the 420-430 MHz segment.

(If we can't use the frequencies, others can, and CityFreq lists the following assigned to other licensees in Detroit:
422.2875 422.8250 424.4875 424.7500 424.8625 425.0250 425.1000 425.1250 427.2250 427.3250 427.4250 427.4750 427.5750 427.6000 427.6500 427.7250 427.8000 427.8250 427.9000 428.2000 428.5375 428.9250 428.9500 429.7625 429.8500 429.9750 )

Cortland
KA5S

 

As a ham near Eglin AFB, I can tell you that the base tends to be quite acommodating to hams who request specified times to breach the 50W restriction. We had a guy once who was doing EME; he basically printed off a list of times the moon would be in the right place for the next year, turned it in to the base. They handed it back with a list of times he wasn't allowed, and voila! permission.

 

So am I. That's why I quit the program a couple of years ago. Those MARS vigilantes are something else!!

Lee
W6EM

 

...and we wonder why so many think Amateurs are weird. Jeez...

 

I guess many of us forget that our allocations from 220 MHz on up are SHARED, usually with military interests.

Also, the Line "A" is just a buffer zone along the Canadian border to protect their access. Keep in mind that they've lost the 420-430 MHz spectrum to commercial users now, so there's another SHARED spectrum.

Gary WA7KKP

 

I know that I was not aware of this rule.  The only rule I was aware of regarding the restrictions of 420-450 was along the Canadian border 50 miles inland around the Great Lakes due to Canada's use of 420, (and subsequently MI's), use of 423.xxx-428.xxx MHz for public safety and other "special emergency" use, (eg. ambulance services, hospitals, some fire departments and police agencies, repair crews for utility companies and so on and so forth.)

Thanks for the useful info.

 

Since I think you live in the Tampa Bay Area, if you feel the need to exceed 50W while mobile, chances are that you can apply for permission. I did and received same while I lived in Bradenton.

Also, my sympathies with respect to your dialogue with N1IR over on the UWB thread. He's quite a piece of work.

73,

Lee
W6EM
Leeds, AL

 

Actually, all the band restrictions for 70cm and the exemptions for telecommand and earth stations are fully detailed in the ARRL FCC Rule book in chapter 4, where the band plans are explained. Hard to believe so many hams don't bother to check it out before operating.
KB7HK