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Ham Operator Sets New Miles-Per-Watt World Record
DoctorPepper writes "A ham radio operator in New London, North Carolina correctly copied an 80 meter CW beacon in Wappingers Falls, New York, a distance of 546.8 miles. The kicker is, the beacon station, an Elecraft K1, was putting out 40.6 uW (40.6 millionths of a Watt) -- which works out to 13,467,980 miles per watt!"
Ham Radio continues to excite. I think there's something romantic about it that draws geeks towards its coils - how else do you explain the way it has enthralled so many in its history? The venerable Woz is one. Can anyone else recall any Ham Radio enthusiasts who went onto bigger things in Tech?
Man B: what?
Man A: 13,467,980 miles per watt
Man B: What?
Man A: Watt?
Man B: What!?!?!?
Man A: Watt!!!!
Man B: Forget it, I'm not playing this stupid thing, go be an A$$.
omg.. after reading that article I got the feeling that there are people even more geeky than computer geeks.
"I'm thrilled the record was set by an all-American team using all-American equipment." The Ten Tec receiver is manufactured in Severville, TN and the Elecraft transmitter is produced in California and offered as a kit.
yes, so relevant...
it would be like running doom 3 on a 286.
Even most directional antennas will not give you linear 'watt to distance' amplification.
In worst case it is a power^1/3. So for 40 milliwatts to 1 watt amplification you'll get some 30x distance (at worst), but never 2500x, unless some wicked atmospheric conditions happen.
This seems an odd way to compare accomplishments. If you use this metric, then you reach the false conclusion that doubling wattage doubles distance. Since signal strength deteriorates with distance squared, a better metric might be miles^2 per Watt.
Example using round numbers. Philip transmits 10 miles using a 10W transmitter. Sally transmits 19 miles using a 20W transmitter. If you use miles per Watt to compare, it looks like Philip achieved better results, when in fact Sally did.
Commenting on his remarkable success, Bill said "I've spent 25 years on 80 & 160 listening to below noise level signals ..."
Below noise signals sounds paradoxical, but people do it all the time. If you're in a noisy restaurant, you can pick out individual noises even though they are much quieter than everyone else. The key is that you have an idea of what you expect to hear - you generally know the tone of their voice, know what sounds make words, know what words make understandable sentences.
Imagine if the signal had been spread-spectrum. Spread-spectrum signals are stealthy because, they to, can be recovered from below the noise floor. Basically, with an idea of what to expect, the receiver's processing can effectively raise the signal above the noise floor. Instead of sending short tones for each bit, a series of tones are sent for each bit (a chip) - one chip for zero, and a different chip for one. It's a lot easier process a sound and see which chip it sounds closer to than it is to see if one particular tone is there or not.
So, in summary, this guy's brain played a lot in the reception to pick out a signal from the noise. I wonder if the next record will be set with a spread spectrum transmitted signal and a digital processing receiver.
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Many people have made the comparison to the internet or other wireless technologies. There may be some relation if your only purpose is to talk over a distance. There is however a big difference. All of the services (internet, phone, cell phone) in use by the majority of people require network support. A ham can communicate with none. In an emergency the phone and network services can be interupted by damaged circuits loss of power or just congestion making it impossible to get a message through. The last communication service funtioning will be the hams. Real life example from a call that I relayed. Power and phones were out in a section of the city and a man's wife collapsed. Luckily he was a ham and grabed his radio. I took his info and relayed to it to the fire department and the paramedics were there withing five minutes.