LMS TxLO noise

Thomas Tsou ttsou at vt.edu
Mon Jul 30 02:37:54 UTC 2012


Hi Andrey,

Parts arrived yesterday and I made modifications for the 100 kHz loop
filter and tested today. The entire 900 band is below 1.5 / 5 with a
good margin.

http://filebox.vt.edu/users/ttsou/http/umtrx_945mhz_4.bmp

The lower part of the 1800 is also below the target value. I was not
successful at 1885 MHz, though further calibration is possible (manual
calibration at each frequency takes a very long time). I will perform
additional tests tomorrow.

http://filebox.vt.edu/users/ttsou/http/umtrx_1825mhz_4.bmp
http://filebox.vt.edu/users/ttsou/http/umtrx_1825mhz_noise.PNG

  Thomas

On Wed, Jul 25, 2012 at 9:52 PM, Thomas Tsou <ttsou at vt.edu> wrote:
> On Wed, Jul 25, 2012 at 1:41 PM, Andrey Sviyazov
> <andrey.sviyazov at fairwaves.ru> wrote:
>> Hi Thomas.
>>
>> Digikey part numbers links:
>> C82 = 100pF, C83=1500pF, C84=33pF, R106=2.2k, R109=3.3k, L6=0.022uF.
>>
>> But you'll remove 100pF capasitor from position C45, so you could use it for
>> C82.
>> BTW, how long time required to delivering from the DigiKey?
>
> Thank you for the links. Parts are ordered. Digikey orders usually
> arrives in 2 days.
>
>   Thomas




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