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Re: Pacsat question



> >> A few ops also said that the
> >> image files from the 9600 birds are much better than that of the
> >> 1200's.

> There would be no
> different in the image quality from a 1200 vs. 9600 baud satellite.  The
> different is in how long it takes to upload and download the image from the
> satellite.

Someone has, I suspect, introduced some confusion. A digital image is a
digital image is a digital image. Internal quality remains the same however
you get it.

OTOH if the point is about images *taken by* the satellites ... the only
1200 with a camera is WO-18 (I believe its an NTSC box) and the quality of
its images is poor compared with all the other cameras (which are on 9600's).
WO-18 seems to crash much more often than the other birds.

I'm not sure of the file-size of a WO-18 image; I'm told it takes several
passes to download one. Images snapped by the 9600's are of the order of
350K; download time depends on whether you are the only station in the
queue or just one of many taking their time-slots. With a full queue it
can take more than one pass to download an image but if you're somewhere
remote and have the spacecraft to yourself then (I guess) it will take
about half a pass to download. Of course, with a popular image and a full
queue you benefit from the broadcast protocol by eavesdropping on other 
folks downloaded parts of the same image.

73
Richard W L Limebear G3RWL
g3rwl@amsat.org
FOC # 1188

          So many beautiful girls ..... (sob) so little time



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