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Comment Re:Buy an rf jammer, become a drone collector (Score 1) 1037 1037

... illegally transmitting in restricted spectrum.

2.4 GHz is some of the _least_ restricted RF spectrum, FWIW.

Too bad I can't charge for using Amateur radio - I can legally transmit up to 1500W into the antenna on that band (2300-2450 MHz) with no restriction on Effective Isotropic Radiated Power. Here's a 1.0x0.6 m somewhat paraboloid antenna that has 24 dB gain in a 10x14 degree pattern, making the EIRP 377kW. I bet that would pop the radios in that drone.

(Naturally I'd never do this - according to RF exposure limits, that setup would exceed the limits for uncontrolled human exposure out to 180 feet or so).

Comment Re:Safety (Score 1) 63 63

They may be, given the horrendous loss involved and the use of directional coupling. That 50 Watt limit is not absolute, it's more of a guideline for Amateur radio stations specifically, not all emitters. Your cell phone at < 4W is also closely regulated due to its proximity to human tissue. Please refer to the FCC RF exposure site for the full regs.

RF exposure is a function of frequency, duty cycle, distance, transmitter power, and antenna gain. I have a tiny 10mW 10GHz transmitter that couples its power via WR-90 waveguide. If my math is correct, that's 3.1 mW/cm^2 at the mouth of the waveguide - WAY over the exposure limit of 1.0 mW/cm^2 at 10 GHz for uncontrolled access.

Remember, sunburns are actually RF burns.

Comment Re:Safety (Score 1) 63 63

Magnetic fields don't hurt you

STATIC magnetic fields don't seem to hurt you. Time-varying magnetic fields most certainly can hurt you. In addition to ionizing radiation (x-rays, gamma rays) which can obviously hurt you, plain old radio waves can too:

Radiation burns can also occur with high power radio transmitters at any frequency where the body absorbs radio frequency energy and converts it to heat.[1] The U.S. Federal Communications Commission (FCC) considers 50 watts to be the lowest power above which radio stations must evaluate emission safety. Frequencies considered especially dangerous occur where the human body can become resonant, at 35 MHz, 70 MHz, 80-100 MHz, 400 MHz, and 1 GHz.[2] Exposure to microwaves of too high intensity can cause microwave burns.

Comment Pot, meet Kettle (Score 1) 574 574

It's about sound quality. I don't need my music to be devalued by the worst quality in the history of broadcasting or any other form of distribution.

Neil Young complaining about sound quality??? Neil Young, one of the worst-sounding singers on the planet??? Please.

Comment Re:Might make sense (Score 1) 87 87

I agree with your points - they're all well-reasoned.

What I haven't seen mentioned is the case where the drone arrives first and it's video shows the dispatchers that the fire is much larger/more involved than first reported so the dispatcher can roll additional equipment to the scene while the original trucks are still en route. That would be a major plus for having the drones.

Similarly, if the drone finds that the original report of a massive fire is more like a tiny shed on fire, they could cancel some of the equipment en route, freeing it up for other calls.

Another case: A train derailment or tractor-trailer accident. Much of the cargo carried in tank cars is in some way hazardous, and it would be very handy if a drone could show the dispatcher what placard numbers* are involved so that they can coordinate cordoning off the area and possibly evacuating residents. It would also help in making sure you have the right firefighting chemicals around - lots of hazardous stuff requires foam to extinguish and reacts rather violently with good old H2O.

*If you've never read the Emergency Response Guide, you should. Some of the nasty stuff that's hurtling down the highway next to you is very dangerous and/or toxic. It's eye-opening, to say the least.

Real programmers don't bring brown-bag lunches. If the vending machine doesn't sell it, they don't eat it. Vending machines don't sell quiche.

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