LMS TxLO noise

Thomas Tsou thomastsou at gmail.com
Thu Jul 19 14:45:04 UTC 2012


Hi Andrey,

On Thu, Jul 19, 2012 at 10:10 AM, Andrey Sviyazov
<andrey.sviyazov at fairwaves.ru> wrote:
> Hi all.
>
> I've found spurs on the LO noise plot at  ~33kHz and ~66kHz offset when GPS
> antenna used and position locked.
> This spurs begin grow up when GPS just near to lock position and after
> locking spurs stopped to grow as you can see at picture.
> If thereafter GPS disconnected then noise coming back to normal plot.
> I think that it is result of 32768Hz clock in the GPS module EB-230, but
> can't understant how it can impact to 26MHz clock or VCO.
> Please tell me something who know.
>
> Thomas.
> Was GPS antenna connected when noise measured like on the picture which you
> sent us (also attached here)?
> I would to know because of anomal peak near to 30kHz offset too.

I have not connected a GPS antenna for any of the tests. I will run
some measurements with register 0x16 later today.

  Thomas




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