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Re: Orbit 250 apogee

At 19:22 16-05-2001, you wrote:

>I can't speak to power, but there are 2 different S antenna/transmitters on
>AO-40. S1 uses the dish and S2 uses the helix. The antennas and transmitters
>are dedicated i.e. you can't put the helix into S1 xmtr and vice versa. The
>dish has 8dBi more gain (as I recall) But, here's the rub, with more gain
>comes a tighter pattern. So, while the S1 xmtr/dish combination will be great
>near perigee, you must remember there is more path loss. As AO-40 heads
>towards/away from perigee, the S2 helix should be better because of a wider
>pattern. The dish will remain very good near perigee, but the optimal
>footprint will be smaller due to the tighter pattern.
>That's my understanding of the antennas after studying them. I could be way
>off base........ Work on your receive system. <grin>

I think you are spot on, Mike..

73 de OZ1LRG

"A closed mouth gathers no colesterol"

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