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Emergency Cellphones That Work Without Phone Towers Or Satellites

A cellphone that can work when phone towers and satellites are not available

Doctor Gardner-Stephen using his reprogrammed cellphone to talk to his team of researchers during testing in the Outback desert and Flinders Mountain ranges of South Australia.

It is stories like this that make me proud to be an Australian. A team of Aussie scientists from Flinders University have found a way to re-program mobile phones (cell phones) so they can talk to each other over short distances without working cellphone tower or a communications satellite. This would make these cellphones ideal for emergency communications in a disaster situation, like the recent major earthquake in Port au Prince, Haiti.

These radio boffins have been testing out their modified mobile phones in remote desert areas of South Australia that are hundreds of miles or kilometers from the nearest cellphone towers. The researchers have even been in deep canyons, and the cellphones are able to talk to each other over a distance of a few hundred yards (meters) or so.

The modified cell phones are models that already have an inbuilt WiFi feature, and the boffins re-programmed the phones to make calls to each other using just the WiFi signals. Normally wifi transmissions are used over very short distances, to link computers and their peripheral devices, such as wireless-enabled printers, optical scanners, hard disk drive remore storage, or from computer to computer. But here the WiFi works from phone to phone, making phone towers (computer controlled radio repeaters) unneccesary.

It was Aussie ingenuity like this that created the original Outback pedal-operated radio transmitter-receiver that remote Outback cattle stations (ranches) could use to call for help from the Royal Flying Doctor Service.

For further details, click on the photo (above). The link will send you to the original article, which is on the Australian ABC News web site.

2 comments - What do you think?  Posted by Admin - July 12, 2010 at 01:07

Categories: Emergency Communications   Tags: cellphone, disaster communications, emergency radio, Haiti earthquake, mobile phone, outback radio, safety radio, wifi communications

Radio Repeaters Extend the Range of VHF and UHF Two Way Radios

To get the maximum possible range for a radio transmitter, the radio's antenna should be up as high as possible. That is why professional radio installations, business, government agencies, police fire and emergency services all have their radio antennas placed up as high as possible. And they often use radio repeaters as well.

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Be the first to comment - What do you think?  Posted by Admin - July 11, 2010 at 06:35

Categories: Long Distance Radio   Tags: 2 way radio, ACMA, amateur radio, cb radio, duplex channels, emergency radio, fcc, frs radio, government radio, ham radio, longer distance radio, mobile radio, portable radio, public service radio, radio repeaters, radio towers, simplex channels, two way radio

Long-Distance Radio

Two way radio has progressed a very long way (pun intended) since it was first invented around 1900, however people have always had a desire to get their radio signals out further. Let me explain how radio developed and what has been involved in getting those radio transmissions to work over longer and longer distances.

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Be the first to comment - What do you think?  Posted by Admin - July 6, 2010 at 02:35

Categories: Long Distance Radio   Tags: first walkie talkie, ground wave, Guglielmo Marconi, line of sight, low-frequency radio signals, maritime radio, MF or HF bands, morse code, radio propagation, ship to shore radio, spark gap, spy radios, suitcase radios, trans atlantic radio

Why do most all TWO-Way Radios (GMRS/FRS) boast such a huge range, when in fact range is significantly less?

For example, I am very interested and will most likely purchase a new 2-way radio (GMRS/FRS), specifically the Cobra LI-7200/2WXVP GMRS 2-Way Radio Value Pack that boasts a 27 (that’s TWENTY-SEVEN) mile range, when, in fact, from reading many, many reviews, the most that has been reported is maybe 2 miles?

Now, I understand that there are MANY factors involved, such as urban usage – buildings, houses, cars, trees, etc., but seriously, that is more than a 75% difference. Where are “they” coming up with those astronomical figures? Are the using the ocean, or airspace as their testing grounds?

You know, Walt Disney World covers about 47 square miles which is about the size of San Francisco or two Manhattan islands – so what good are these or any other two-way radios?

If you mention skiing in the mountains, don’t bother cause I was using a 2-way radio while skiing in Colorado and took a wrong turn and ended up literally in the streets of town and I couldn’t contact any of my party for assistance which led me to walking 2 miles in my rented ski-boots just to find a bus. Now, I am from Florida and let me tell you, we aren’t used to ski boots when they are attached to skis, so don’t think us boys down here like them any better now.

A GMRS license? Yeah, right. Then why don’t they include one (or information)when you purchase any GMRS 2-way radios that are for sale to the public? The ones I am referring to are the maximum power output allowed by law.

It sounds to me like “false advertising”, in which case, a lawsuit should be filed, eh?

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2 comments - What do you think?  Posted by Admin - May 19, 2010 at 10:03

Categories: CB and FRS Radio   Tags: 2 way radios, astronomical figures, cobra, false advertising, GMRS license, maximum power output, radio value, ski boots, skiing in colorado, skis, two way radios, walt disney world

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