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W8MI! Whiskey right Mexico India… Dennis, do you read me?
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Can I just, like, text you next time? This is weird...
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Can you read me DNews, what's your 20?
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Sciencemen Trace here hamming it up for DNews.
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Remember that time Eleven needed to talk to Will in the upside-down?
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The kids were excited because they got to use a ham radio.
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Ham radio is an amateur radio broadcasting system -- people who operate ham radios are
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called "hams!"
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There are nearly three million ham licenses worldwide: with major populations of hams
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in Japan, Germany, England, Indonesia, South Korea.
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According to the National Association for Amateur Radio, there are more than 727,000
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licensed ham radio operators (called hams) in the U.S. -- making us the second largest
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community.2
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I say community, because that's what amature operators says it's all about.
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Ham radios are exactly like any other radio, but instead of your local rock, country, or
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Beyonce station playing nothing but the hits, nothing but the hits…
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Instead, it's Jenny from the block, Sloan from Canada, or Siso from Swaziland; right
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there, in your radio!
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Aside from the fun community aspect, in times of disaster, when cell towers and internet
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are down, hams can still communicate with each other and emergency services.
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All radio works the same, even ham radio.
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When electricity travels through an antenna of some kind, another antenna can pick it
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up and decode it.
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Tune a radio to a static AM station, grab a nine volt battery and a coin, hold them
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near the antenna and connect the studs with the coin.
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The radio will pick something up!
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The electricity is "broadcasting" radio5.
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The battery will only go a few inches, but with more power, the signal can go farther.
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Thanks to advances in technology, we can pinpoint exact frequencies to broadcast on, where the
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radio waves are precisely tuned so they don't interfere with each other.
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According to HowStuffWorks, ham bands are "above the AM radio band (1.6 MHz) to just
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above the citizens band (27 MHz) (also known as CB radio!)"
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And on those ham bands, the FCC says people can send 1,300 different types of communication
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using voice, video, digital, telegraphy (morse code!)... you name it -- it's all shared space,
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though.
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So if someone else is using that frequency, it becomes a party line.
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There are three main Ham radio bands: HF, VHF, and UHF.
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With UHF or "ultra high frequency" the waves leave the antenna and bounce off buildings
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and around solid things, but can't go2 around mountains.
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VHF "very high frequency" waves can pass around some obstacles, but can still be blocked.
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These are mainly "line of sight" antennas.
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Straight lines.
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Think FM radio.
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Which is why it doesn't work over the curve of the Earth or behind a mountain.
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But, that doesn't stop all radio.
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HF "high frequency" waves are my favorite in this scenario…
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Because, starting about 50 kilometers above you is the ionosphere -- an electrically charged
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layer of the atmosphere.
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Ham radios using the HF range can bounce their waves off the ionosphere, creating a Sky Wave.
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That wave "skips" to another point on the Earth… or hits another antenna -- which
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might rebroadcast it!
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All ham signals can be rebroadcast… someone can pick it up, and send it out again.
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Like a relay!
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I wasn't kidding when I said Swaziland!
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But Swaziland isn't the furthest radio can reach.
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In 1969, an operator in Louisville, Kentucky picked up radio between Armstrong and Aldrin
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on the moon during Apollo 11.
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He even recorded President Nixon's message to them!
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You can still talk to astronauts with amature radio today.
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The ionosphere doesn't bounce all signals!
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On the International Space Station, the crew has access to a ham radio.
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When they're overhead, their 2-meter FM transceiver allows the ground can have a chat with space.
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You can see for yourself that the astronauts are overhead, talk to them while they're there,
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and then they fly away.
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TAKE THAT
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If you're fascinated by how far afield ham radios can reach, the new CW show, Frequency
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takes that even further.
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In the show, a female police detective in 2016 discovers she can reach her estranged
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father over the airwaves of her ham radio.
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Plot twist: He's in 1996!
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Don’t miss the Series Premiere of Frequency, Wednesday October 5th, at 9/8c only on The
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CW.
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It's pretty amazing that we can do all this with waves of electromagnetic energy.
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The more you think about it, the cooler it gets.
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Which is why DNews Plus did a whole thing on LIGHT!
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What is it anyway?!
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Wait, what?
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You don't know DNews Plus?
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It's like DNews, but ten times longer.
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We take a big topic, like Artificial Intelligence, Leaving Earth, or Light -- and get nerdy with
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it.
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If you're smelling what we're cookin' subscribe to DNews Plus on YouTube, or listen to it
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as an audio podcast on Soundcloud or iTunes.
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Have you ever tried a ham radio?