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Re: UO-22 azimuth-only system



Hi All,

Dave wrote:

> A friend in Australia wrote a program that attaches to IT, and will switch
> a relay
> to select an antenna that is designed for various elevations.
>
> I use it here in conjuction with a quadrifilar mounted vertically (good
> sigs above
> 30° El), and a j-pole (good sigs to 30° EL).  It works very well, simple,

Interesting how ideas converge! I had ideas on a similar arrangement. For
switching, I pulled the relays out of some very old (free) UHF rigs. (Cheap,
but quite good quality relays!) The plan was to switch them of the PC's
parallel port, one bit per relay. The idea faltered when the "high gain"
collinear omni I had planned to use on the horizon proved useless for
satellites (at any elevation). Not sure why, it's fine for terrestial, and I
thought the lobe on the horizon would work well. For the overhead pass I was
going to use an upward pointing yagi, and my j-pole to fill in the gaps
around 30 degrees.

To drive it (under linux) a simple program to read Easycomm style serial
messages (off a virtual serial port), parse them, and then select the
appropriate antenna. This would let me use a number of tracking programs.

As I mentioned, the omni performance killed the idea, and I subsequently
found that just setting my stacked 8-el yagis to a fixed position would
still get up to 20KB from a UO-22 pass, without tracking.

cheers
Steve


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