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RainyDayNinja
02-09-2011, 09:36 PM
My characters are trying to take over the world, and part of the plan involves broadcasting a kind of mind control signal to influence large groups of people over wide areas. I'm thinking cell phone networks would be the way to go, but I'm having trouble finding the details I need. I'm fine with playing a little fast and loose with the technology, but where would they need to go to tap into the system? Is there some kind of centralized hub that handles the calls, where they could splice their technology in and piggyback on signals across the country?

lbender
02-09-2011, 09:39 PM
Does this signal go directly to the mind, or does it require the recipient to have a device to receive and listen to it; i.e. a cell phone, radio, etc.?

Skyler
02-09-2011, 10:22 PM
Well, basically you have two options.

Either there's a way to feed the signal across the public switched phone network (in which case all you'd need is a cell phone--or even land line), or you'd have to hack each and every cell service provider to hijack their switching centers (more likely). That could take a while.

PeterL
02-09-2011, 10:51 PM
It is technically feasible to broadcast a signal around the world from radio antennae. You would have to boost the output, and there might be dead spots due to interference patterns, but it would work. It the wavelength(s) were an even fraction of the circumference of the Earth, then the waves would start to reinforce themselves.

Skyler
02-09-2011, 10:57 PM
It is technically feasible to broadcast a signal around the world from radio antennae. You would have to boost the output, and there might be dead spots due to interference patterns, but it would work. It the wavelength(s) were an even fraction of the circumference of the Earth, then the waves would start to reinforce themselves.

I thought of that, but you also have propagation issues depending on solar activity, weather, and so forth. It's too unreliable.

Stanmiller
02-09-2011, 11:11 PM
Research ham radio. They do it all the time.

PeterL
02-09-2011, 11:23 PM
I thought of that, but you also have propagation issues depending on solar activity, weather, and so forth. It's too unreliable.

You'd have those issues with any broadcast signal. Solar activity has knocked out cell phone signals at times. Weather would be a very minor factor, but the change in the height of the reflecting layer would be an issue.

Skyler
02-09-2011, 11:49 PM
You'd have those issues with any broadcast signal. Solar activity has knocked out cell phone signals at times. Weather would be a very moinr factor, but the change in the height of the reflecting layer woul be an issue.

No, I mean it would be significantly worse. In ham radio, you basically take what you can get--intercontinental contact is possible, but weather patterns determine where your signal gets through and where it doesn't. Even relatively minor effects like sunspots affect propagation.

PeterL
02-10-2011, 12:03 AM
No, I mean it would be significantly worse. In ham radio, you basically take what you can get--intercontinental contact is possible, but weather patterns determine where your signal gets through and where it doesn't. Even relatively minor effects like sunspots affect propagation.

It depends on where on the spectrum one is broadcasting. Ham operators have some of the worst part of the spectrum. Weather is relatively minor, except when there is an electrical storm. Radio on better parts of the spectrum and FM get through muc more readily.

Sunspots are a major concern of all broadcasters, and it affects electrical transmission in cables.

Skyler
02-10-2011, 01:18 AM
It depends on where on the spectrum one is broadcasting. Ham operators have some of the worst part of the spectrum. Weather is relatively minor, except when there is an electrical storm. Radio on better parts of the spectrum and FM get through muc more readily.

FM radio is in the VHF band. Propagation there is limited to either line of sight or the unpredictable "sporadic E propagation" reflecting signals off of "clouds" of ionized particles in the lower E region of the ionosphere. In other words, it only rarely transmits inter-continentally, and then it's pretty much accidental. (Also, see tropospheric ducting--dependent on the weather, as I said.)

HF or shortwave radio propagates more reliably in the E region of the ionosphere, but again it's dependent upon the strength of the solar wind. You get better propagation at night and worse during the day.

Anything lower follows the curvature of the earth via groundwave propagation, but suffers from severe attenuation due to the earth's resistance.

Anything higher is more likely to punch through the ionosphere instead of reflecting back down to earth (a necessary prerequisite for getting around the curvature of the earth).


Sunspots are a major concern of all broadcasters, and it affects electrical transmission in cables.

But broadcasts which depend on the state of the ionosphere for propagation are most affected by the presence or absence of sunspots.

Generally it's a Bad Idea for your evil plan to depend on the weather. Just sayin'.

movieman
02-10-2011, 03:23 AM
If you don't need a powerful signal, the simplest solution is satellites: you can cover most of the planet other than the poles with three of them.

Skyler
02-10-2011, 06:00 PM
If you don't need a powerful signal, the simplest solution is satellites: you can cover most of the planet other than the poles with three of them.

What he said. :)

KQ800
02-11-2011, 06:27 PM
My characters are trying to take over the world, and part of the plan involves broadcasting a kind of mind control signal to influence large groups of people over wide areas. I'm thinking cell phone networks would be the way to go, but I'm having trouble finding the details I need. I'm fine with playing a little fast and loose with the technology, but where would they need to go to tap into the system? Is there some kind of centralized hub that handles the calls, where they could splice their technology in and piggyback on signals across the country?

You could go with aircrafts. highaltitude brodcast from a stolen SR-71 or equivalent. If you only need to send once.

If you need to bradcast continously an aerostat might work, a balloon tied to a cable. Take over the major cities, then send minions around with balloons to the smaller ones. Needs a lot of preparation, but equipment could be shipped with fedex if you have minions ready.

Pro, no rocket launch can be detected and balloon takes over minions in largera area as it rises. At 70 000 feet you cover more than 300 miles across with a single aerostat.

Con: Correctly equipped aircraft have ruined ballooners entire day since 1915

movieman
02-11-2011, 06:37 PM
You could go with aircrafts. highaltitude brodcast from a stolen SR-71 or equivalent. If you only need to send once.

It would have to be 'equivalent' unless you're going way out there on the airplane thefts, because a real SR-71 typically needed air-to-air refuelling within a few minutes of taking off and then every few thousand miles of supersonic flight.