RE: [amsat-bb] A few sat questions

[Tony Langdon <tlangdon@xxxxxxxxxxxxxxxxxx>]

> 	1)  With respect to receiving antennas on 435 Mhz,  I put up a
> homebrew "eggbeater" type omni antenna,  using about 40' of 
> 9913 to the
> rcvr.  It is wired for RHCP.  Though the antenna works OK on 
> various passes
> of UO14,  ocassionally bringing the rcvr to "full quieting" , 
> a lot of the
> time during the pass,  the signal just drops out.  Perhaps 
> weakly related to
> the elevation angle,  it is hard for me to tell.  Is this due 
> more to the
> fact that the polarazation from the sat is changing?  I 
> thought that an
> eggbeater would have worked better,  though I realize that an 
> omni ant is a
> compromise.  Do most ops work UO14 with handheld beams ?

I use a handheld beam, which works very well.  For an omni, there's a few
strategies:

1.  Add a tower mounted preamp and polarization switching (LHCP/RHCP).  That
should give you some more performance.  
2.  Use a 2m 1/4 wave (3/4 on 435), and work only the higher elevation
passes (above 30 degrees).  Bob recommends this especially for packet/APRS
users.
3.  If you can manage azimuth rotation only, try a beam with a broad
patterm, such as a TPM II.  (from K5OE).  Again, use a masthead LNA for best
results.> 
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