[hpsdr] Multiple receivers on single mercury with down converters

[Joe Martin K5SO]

Mark, 

It may be that all the discussion regarding phase stability has masked the pertinent answer to your original question of obtaining V and H diversity.  Your suggestion of using dual down converters into a single Mercury receiver running in multiple receiver mode with one receiver tuned to 50 MHz and one to 40 MHz will work perfectly well to achieve polarization diversity, with no special concerns regarding phasing whatsoever.  

For simple diversity operations you do not need to have the two channels coherent.  To achive stable nulls/peaks with manual phasing controls you do need coherence, certainly, but if the goal is to simply obtain polarization diversity you do not need phasing adjustments at all and you do not require coherent receivers to achieve it.  

The scenario you proposed originally will result in an audio stream that contains contributions from both V and H polarized waves; thus you will have polarization diversity operation.  That "non-coherent" configuration will allow you to be immune to "Faraday lock out" conditions on EME, as an example.  No special consideration need be given to the LO soucre(s) for your down-converters, in this case.

73,  Joe K5SO


 1346348117.0