It depends on the level of automation of your station... if you are using fixed antennas, you only need enough accuracy to know when the satellite is in view. If you are using rotor control, it depends on the beamwidth of your antennas ( the narrower the beamwidth, the more critical the aiming becomes). If you are using doppler control, then very high accuracy is needed: a few seconds of error can translate to several hundred hertz of doppler shift on a high pass.

I have my XP machines set to check an internet NTP server every 4 hours. For Field Day, I use a GPS receiver to keep the PC clock dead on, and always use GPS to set my station coordinates accurately when portable. And when in doubt, I update my keps right before operating, and at least once a week otherwise.

George, KA3HSW

----- Original Message ----- From: "Stargate" stargatesg1@verizon.net To: "Amsat-Bb" amsat-bb@amsat.org Sent: Thursday, August 24, 2006 4:29 PM Subject: [amsat-bb] Accuracy?

I guess my question should be....How much accuracy is required for satellite communications?

Thanks, RoD KD0XX