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If the transmitting aerial is horizontal then most of the power goes only at right angles to the line of the aerial and you 'loose' a lot of power transmitting up and down. Also the receiving aerial needs to be in the horizontal plane for good reception efficiency. This is fine perhaps ever preferential if you know where you're transmitting towards (and want to minimise the chance of interception) but for general broadcast you want a vertically aligned aerial.
Doctor Prepper: What's the worst that could happen?
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Interesting. How do the US DoD do this with the VLF antenna which cover large areas of land? No way does that go up in the air.
Skean Dhude
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It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change. - Charles Darwin
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The lower the frequency the less directional but the footprint of a horozontal aerial is far from circular
Doctor Prepper: What's the worst that could happen?
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Makes sense and with a wavelength that size it probably covers the solar system anyway.
Skean Dhude
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It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change. - Charles Darwin
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Ex-scaleyback here.
My VHF/hf days were a few years ago now and my knowledge is rusty although I am prone to chattering out a bit of morse on my teeth now and then!
This technology is only used now by hobbyists. I would say its not worth pursuing unfortunately. If you are in a big group, hand held personal radios are the best bet. The range is upto a couple of K's.
Mobile phone coverage would last last 24 to 72 hours if anything kicks off (my field of expertise nowadays)
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I just wondered, if you are transmitting can TPTB triangulated your position, like the Nazis used to do in WW2?? i'm not technically minded to start with, so whilst i have a wind up radio to receive news will be keeping a low profile especially after TSHTF.
Some people that prefer to be alone arent anti-social they just have no time for drama, stupidity and false people.
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All transmissions can be triangulated. It is easy to do with simple receiver of that frequency.
Mobiles, CB, Walkie Talkies,etc. If it transmits you can locate it while it is transmitting.
Skean Dhude
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(15 November 2011, 13:06)Skean Dhude Wrote: All transmissions can be triangulated. It is easy to do with simple receiver of that frequency.
Mobiles, CB, Walkie Talkies,etc. If it transmits you can locate it while it is transmitting.
thats what i thought, after TSHTF the mobile gets chucked away and i keep a VERY low(i.e.hidden) profile.
Some people that prefer to be alone arent anti-social they just have no time for drama, stupidity and false people.
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Any transmitter can be triangulated (DF'd). Simple measures can counteract this. Maintain radio silence (self defeating in a way) and keep radio transmissions to a minimum. Do not transmit for more than 20 secs so as to provide less of an opportunity to transmit your location.
Mobile phone operators use distance to base station calculations to determine locations for as long as the mobile is switched on.
Unless you are a major criminal, I wouldn't worry about things like this.
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