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Re: drifting on AO-7

Perry Yantis wrote:

Some stations seem to be drifting so bad you have to chase them down the band.
How can you have a nice qso that way??
This causes interference to others on the band????

Wayne replies:

I had a serious case of "operator error" on the AO-7 pass yesterday evening.  Last weekend I made 100+ Field Day contacts using InstantTrack/InstantTune.  At my home station I use SatPC32 for satellite tracking and Doppler tuning.  Last night at the home station my BRAIN was still in "InstantTune" mode.  I was frantically twisting the FT-847 sub-tune knob trying to adjust my TX offset frequency.  But every 3 seconds or so SatPC32 would write a new TX frequency to the FT-847.  It wasn't until the pass was almost finished that I realized that I must adjust my TX offset frequency via the computer keyboard instead of the sub tune knob.

Next time I won't make that mistake.  I also use computer-controlled full Doppler tuning, so I won't be the one drifting across the passband.  Manual Doppler tuning can get pretty messy on a LEO satellite, especially for a high-elevation pass where other stations often have "opposite" Doppler shift.  i.e. the satellite approaching one location while moving away from another location.

Wayne Estes W9AE
Mundelein, IL, USA

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