[hpsdr] Introducing Angelia

[Joe Martin K5SO]

Hi Phil, 

That is wonderful news!!  In fact, if the "phase word" approach works for multiple Mercury boards too then this may be the breakthrough approach I was seeking and could make using perhaps up to five Mercury boards for DF and beam steering feasible with the Atlas bus.  

I'll definitely check it out!  Great observation!   Thanks!!

73,  Joe K5SO

On Aug 5, 2012, at 1:08 AM, Phil Harman wrote:

> Hi Joe,
>  
> There may be a solution to this issue.  I’ve been writing the code to turn Hermes into a Vector Network Analyser. IN which case I need to guarantee the phase relationship between the Tx and Rx is totally consistent and repeatable across numerous power cycles.  Since the Tx and Rx FPGA code  run off the same clock on the Hermes board then that is half the problem solved.
>  
> What I found is if I feed the same frequency to the individual frequency-to-phase converter code for the  Tx and Rx CORDICs then every time I change frequency the phase relationship varies in a totally uncontrolled manner.  However, if I calculate the phase word from the frequency and feed the phase word to *both*  CORDICs then the phase relationship is rock steady under all conditions that I’ve tested so far.
>  
> In which case if we run all the Mercury boards off the same 122.88 MHZ clock and feed the phase word, calculated in say Metis,  over the Atlas bus rather than the frequency then we may find an improvement.
>  
> 73 Phil....VK6APH
>  
>  
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