Friday, July 25, 2008

Position as of 22:40 PDT 7/24/08

Compromise is the Kelly Green dot (position as of 22:40 PDT 7/24/08)
I spoke with Dave E again yesterday - still having problems with SailMail. They are able to communicate with SSB, the computer is fine, the modem is set, and the propagation tables show frustratingly clear signals. Dave E noted that this has become a topic for discussion at Children's Hour with other boats having similar problem. My attempts to troubleshoot from the shore have not yet met with success.
  • Higher frequencies in the late afternoon/early evening
  • Shut off your inverter
  • Shut off all other electronics and motors.
  • Check that your Clarifier, Clarity, or RIT control is centered or turned off.
  • Check that while transmitting during a SailMail connection that your SSB draws about 10-15 amps more during transmit than during receive. If it doesn't you either have your modulation levels set incorrectly or may have a bad connection to your tuner, antenna, or ground.
  • Generally the highest frequency that works will give you the best transfer rate because there is less multipath,
  • The 13 and 18 MHz frequencies work best in the afternoon, generally at distances over 1000 miles.
  • The 5 and 7 MHz frequencies work best during the night or early morning, generally at distances under 3000 miles.
  • 10 MHz is a pretty good bet just about any time for distances over 1000 miles
Dave T

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