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<DIV>Hi Andrey Sviyazov</DIV>
<DIV> </DIV>
<DIV>I confirm that both UmTRX's runs with the same FPGA images (and
firmware). I have updated them to the latest version.</DIV>
<DIV>I will try some other programs to check the problem.</DIV>
<DIV> </DIV>
<DIV>Best Regards,</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:andreysviyaz@gmail.com">Andrey
Sviyazov</A></DIV>
<DIV><B>Date:</B> 2013-08-03 00:54</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>; <A
href="mailto:alexander.chemeris@gmail.com">Alexander Chemeris</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 class=FoxDiv20130803101810854271>Hi Jiang Wenyi.
<DIV><BR></DIV>
<DIV>
<DIV>Please double check that both UmTRX's runs with the same FPGA images (and
firmware).</DIV>
<DIV>If absolutely the same then seems one board is broken.</DIV>
<DIV>Please double check it also by some other tests to be sure before send
to us for repair.</DIV></DIV>
<DIV><BR></DIV>
<DIV>
<DIV>Best regards,
<DIV>Andrey Sviyazov.</DIV></DIV><BR><BR>
<DIV class=gmail_quote>2013/8/2 jiangwy <SPAN dir=ltr><<A
href="mailto:wyjiang@ljshuoda.com"
target=_blank>wyjiang@ljshuoda.com</A>></SPAN><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"><U></U>
<DIV style="MARGIN: 10px">
<DIV>I try another UmTRX board, and it's OK. The difference from the channel 0
and 1 is very small.</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"
target=_blank>Alexander Chemeris</A></DIV>
<DIV><B>Date:</B> 2013-08-02 17:30</DIV>
<DIV><B>To:</B> <A href="mailto:wyjiang@ljshuoda.com"
target=_blank>wyjiang</A></DIV>
<DIV><B>CC:</B> <A href="mailto:umtrx@lists.osmocom.org"
target=_blank>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 class=h5>
<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 <<A
href="mailto:wyjiang@ljshuoda.com"
target=_blank>wyjiang@ljshuoda.com</A>> 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>> <A href="https://github.com/fairwaves/umtrx_scripts"
target=_blank>https://github.com/fairwaves/umtrx_scripts</A></DIV>
<DIV>></DIV>
<DIV>> On Fri, Aug 2, 2013 at 12:09 PM, jiangwy <<A
href="mailto:wyjiang@ljshuoda.com"
target=_blank>wyjiang@ljshuoda.com</A>> 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 / ïïï õÍòÁÄÉÏ</DIV>
<DIV>> <A href="http://fairwaves.ru"
target=_blank>http://fairwaves.ru</A></DIV>
<DIV>></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>-- </DIV>
<DIV>Regards,</DIV>
<DIV>Alexander Chemeris.</DIV>
<DIV>CEO, Fairwaves LLC / ïïï õÍòÁÄÉÏ</DIV>
<DIV><A href="http://fairwaves.ru" target=_blank>http://fairwaves.ru</A></DIV>
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