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<DIV>umtrx_lms.py --lms-get-rx-lna --lms 1 </DIV>
<DIV>umtrx_lms.py --lms-get-rx-lna --lms 2</DIV>
<DIV> </DIV>
<DIV>then output nothing</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 17:30</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: Re: The Difference of Signal Strength From Two
Channels on The Same Board is Big</DIV></DIV></DIV>
<DIV>
<DIV>Ok.</DIV>
<DIV> </DIV>
<DIV>Also check that a correct input is selected on both chips</DIV>
<DIV>(--lms-get-rx-lna option).</DIV>
<DIV> </DIV>
<DIV>Then, could you check whether this is consistent among both UmTRX you have?</DIV>
<DIV> </DIV>
<DIV>On Fri, Aug 2, 2013 at 12:55 PM, jiangwy <wyjiang@ljshuoda.com> wrote:</DIV>
<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>
<DIV>> ________________________________</DIV>
<DIV>> jiangwy</DIV>
<DIV>></DIV>
<DIV>> From: Alexander Chemeris</DIV>
<DIV>> Date: 2013-08-02 16:20</DIV>
<DIV>> To: wyjiang</DIV>
<DIV>> CC: UmTRX</DIV>
<DIV>> Subject: Re: The Difference of Signal Strength From Two Channels on The Same</DIV>
<DIV>> Board is Big</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 / §°§°§° §µ§Þ§²§Ñ§Õ§Ú§à</DIV>
<DIV>> http://fairwaves.ru</DIV>
<DIV>></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>-- </DIV>
<DIV>Regards,</DIV>
<DIV>Alexander Chemeris.</DIV>
<DIV>CEO, Fairwaves LLC / §°§°§° §µ§Þ§²§Ñ§Õ§Ú§à</DIV>
<DIV>http://fairwaves.ru</DIV></DIV></BODY></HTML>