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randall1959

I was wrong......I'll admit it......

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Last night I was listening to Art Bell. I'm a long time listener. He broadcast a story last night about a gentleman, somewhere here in the states, that had a television that was sending out a beacon, somehow on 1.2 ghz. According to the story this is an aircraft locator beacon frequency in the event of a crash. Before long, the FCC was on his doorstep DEMANDING that he turn off that beacon NOW :angry:

After some investigation, they found the offending television and he disconnected it. I'm not sure who the manufacturer was, but that's not the issue. The manufacturer has offered to trade him a working set for his, so that they can do further study on what went wrong. This wasn't stated in the newspaper article, but maybe Mr Bell got the story after the manufacturer got wind of it.

Having heard that, all my 1.2 ghz stuff went to the dump(most of it was broken anyway) this morning. Why take chances when there is perfectly legal stuff out there for comparable prices?

http://www.katu.com/news/story.asp?ID=71894

Edited by randall1959

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Randall1959

I went to the link that you posted and and I think that you are a bit confused.

The frequency that the TV was emitting was 121.5 MHz not 1.2 GHz.

I am not aware of any aircraft locator beacons in the 1.2 GHz band how ever the 121.5 MHz is in the VHf aircraft band and is what we in the Air Force called the Guard channel it is monitored by the Air Force, the Air National Guard, the US. Coast Guard and most commercial airliners wile in flight and by satellites.

It is used to locate downed aircraft.

The locator units are called ELT or Emergency Locator Transmitters An ELT is a device that transmits on 121.5, 243.0, and 406.0 MHz. The transmission is tracked by SAR (Search and Rescue) to assist in the rescue.

See http://www.avionix.com/elt.html for more information.

The military version of it is on the 243.0 MHz in the lower end of the UHF band.

If you take a look at the first two frequencies 121.5 and 243.0 you will see the 243.0 is twice the frequency of 121.5 this is done that a UHF receiver could receiver 121.5's 2nd harmonic that would be 243.0 MHz.

Some of the newer units have GPS receivers built in to transmit the last known good position of the aircraft. There is a version for boats called an (EPIRBs), Emergency position indicating radio beaconshttp://www.sarsat.noaa.gov/emerbcns.html

So you hurry you could get to the dump and get your 1.2 GHz stuff back.

Dave Jones

AUAV.net

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OOPS.......my bad........ok, since you are as well versed as you are, what is the 1.2 ghz band used for? Here on this site it's reputed to be something about aircraft navigation........

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When I did I came across a whole list of search results.........which one should I go to after that comes up?

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The issue is that the low cost imported video Tx's have yet to be found to use the legal areas of "1.2Ghz" band. Those that have been tested have come up around 1.15Ghz or so. That is a reserved area and not available to us mortals, even with a ham license.

The more expensive "1.2Ghz" systems are available on 1.24Ghz to 1.3Ghz. They are legal for ham licensed use. These are sold by reputable ham radio suppliers that carry ATV components.

Please see this Freq allocation list for more info: http://www.panix.com/~clay/scanning/frequencies.html

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On ebay, there are some 1.2ghz transmitters that are now coming out with switches on tx and rx instead of the rotary tuner. I'm wondering if any of those are legal now? I might bid on one as they are pretty cheap and see what frequency they are really on.

I was told by cctvwholesalers, that the lower the frequency, the better the signal will be, or at least less directional.

Thank you for posting that list Mr RC CAM. I had been trying to find that forever.

Edited by randall1959

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On ebay, there are some 1.2ghz transmitters that are now coming out with switches on tx and rx instead of the rotary tuner.

A few weeks ago I emailed one of the sellers of those systems with my simple sales questions. They wouldn't tell me the EXACT frequencies that were transmitted. I suspect that means something.

A few months ago one of the folks on another R/C forum bought a "1.2Ghz" system with DIP switches and measured the frequency. Like the systems with the tuning knob, it wasn't USA legal. It came from a USA based online retailer that marketed to R/C modelers. The retailer claimed it was legal. I guess they were not aware of their equipment's actual operating frequency. ;)

And here in the USA, when we speak of "legal," there are basically three levels of "legal." [1] Part 15 labeled equipment is legal for use by anyone (the FCC assigned registration number will be printed on the transmitter). [2] RF devices that meet the amateur radio requirements are legal for use by licensed hams (this is what covers our wireless video hobby activities). [3] Devices that do not meet either are off limits. They are reserved for commercial or government use. To date, the cheap eBay units fall into the last category.

Edited by Mr.RC-Cam

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I emailed cooleyes as to the legality of their units and never got a reply. I just asked if these frequencies were legal in the US.

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