[Moon-net] one-way propagation

[David Anderson GM4JJJ]

MoonSked calculates the optimum transmit pol if you know which RX pol  
is best at the time.

MNR is really an indication of how non reciprocal the EME path will  
be (caused by the combined effects of Faraday rotation and Spatial  
offset.

Where MNR comes in is when both stations have fixed polarisation and  
they want o avoid the 'one-way' effect that we get when spatial  
offset is 45 or 135 degrees. At these times one station will hear the  
other but not vice versa.

Of course if one station has switchable polarisation then this is not  
a problem, provided that the station realises that he needs to use  
the opposite polarity on TX from RX periods. Moonsked shows you what  
TX polarisation to use when you know what RX polarisation is giving  
best results. Note that with just 2 polarisations it is sometimes  
difficult to tell which is best so you can still make the wrong  
decision.



On 4 Mar 2007, at 19:15, Heinz Bordé wrote:

> Perhaps someone can tell me the law so I can react with my antennas  
> to the values, WSJT (an even other moon tracking programmes as  
> well) tells me.

73
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David Anderson, GM4JJJ         E-mail: david at gm4jjj.co.uk
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