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<DIV>I use the following command</DIV>
<DIV> </DIV>
<DIV>./umtrx_lms.py --lms {1,2} --lms-get-rx-vga2-gain </DIV>
<DIV> </DIV>
<DIV>the outputs are all the same ( 15 ).</DIV>
<DIV> </DIV>
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<DIV><SPAN>jiangwy</SPAN></DIV>
<DIV> </DIV>
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<DIV><B>From:</B> <A href="mailto:alexander.chemeris@gmail.com">Alexander
Chemeris</A></DIV>
<DIV><B>Date:</B> 2013-08-02 16:20</DIV>
<DIV><B>To:</B> <A href="mailto:wyjiang@ljshuoda.com">wyjiang</A></DIV>
<DIV><B>CC:</B> <A href="mailto:umtrx@lists.osmocom.org">UmTRX</A></DIV>
<DIV><B>Subject:</B> Re: The Difference of Signal Strength From Two
Channels on The Same Board is Big</DIV></DIV></DIV>
<DIV>
<DIV>Hi Jiang,</DIV>
<DIV> </DIV>
<DIV>Are you sure you're setting Rx gain properly for both channels?</DIV>
<DIV>I recommend you to use umtrx_lms.py script from this repository to</DIV>
<DIV>check Rx LNA and Rx VGA settings for both LMS chips:</DIV>
<DIV>https://github.com/fairwaves/umtrx_scripts</DIV>
<DIV> </DIV>
<DIV>On Fri, Aug 2, 2013 at 12:09 PM, jiangwy <wyjiang@ljshuoda.com> wrote:</DIV>
<DIV>> Hi Alexander Chemeris,</DIV>
<DIV>></DIV>
<DIV>> According to rx_multi_samples , I write a program to receive samples from</DIV>
<DIV>> two channels on the same board.</DIV>
<DIV>> The program receive samples from 2 channels and calculate the signal</DIV>
<DIV>> strength respectively. The signal is from a BTS arround.</DIV>
<DIV>> I find the difference of signal strength is very big, about 20dB, and</DIV>
<DIV>> channel 1 is bigger than channel 0.</DIV>
<DIV>> I exchange the antenna and feeder of the them, but the result is same.</DIV>
<DIV>> I think there is some problem, but I cann't find it.</DIV>
<DIV>> Would you please give me some sugguestion?</DIV>
<DIV>></DIV>
<DIV>> Best Regards.</DIV>
<DIV>></DIV>
<DIV>> ________________________________</DIV>
<DIV>> Jiang Wenyi</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>-- </DIV>
<DIV>Regards,</DIV>
<DIV>Alexander Chemeris.</DIV>
<DIV>CEO, Fairwaves LLC / ООО УмРадио</DIV>
<DIV>http://fairwaves.ru</DIV>
<DIV> </DIV></DIV></BODY></HTML>