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Ham Operator Sets New Miles-Per-Watt World Record

Posted by timothy on from the bend-it-like-an-ionospheric-layer dept.

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!"

3 of 403 comments (clear)

  1. It is non-linear by frakir · · Score: 5, Informative

    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.

  2. Miles per Watt? by c++ · · Score: 5, Informative

    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.

  3. Re:Even when it's horribly outmoded... by s4ltyd0g · · Score: 5, Informative

    Outmoded you say? Here's a recent example that may make you change your mind on that one.

    http://www.voanews.com/english/2005-01-05-voa24.cf m