|
From: | Dan CaJacob |
Subject: | Re: [Discuss-gnuradio] URSP noise |
Date: | Tue, 11 Nov 2014 11:37:52 -0500 |
Dan:
That's generally good advice, with the single exception of the BASIC/LF card family--they don't have any gain--they're just ADC/DAC buffers, so it's generally safe to loop them directly.
On 2014-11-11 11:27, Dan CaJacob wrote:
Hi Lucas,You say you connected TXA to RXA directly via a cox cable? Did you put an attenuator inline? I am afraid you may have damaged your RX side by transmitting directly into it without protection. Most USRPs can be damaged with input power greater than -10 dBm. Disconnect that cable immediately and try testing the RX side alone to make sure that it is not damaged. Then, if you want to go back to a looback test, make sure that you put about 60 dB of attenuation between the RX and TX ports.The noise you were seeing was almost certainly not a problem with your source block, but your RX being over-driven (dying).Good luck.
Very Respectfully,
Dan CaJacob
On Tue, Nov 11, 2014 at 11:07 AM, Lucas Lopez <address@hidden> wrote:
hi everyone. i was working with the USRP1. I'm testing a MOD/DEMOD DBPSK. I have only one USRP, so, i connected TX_A( from daughterboard LFTX-LF) to RX_A ( from daughterborad LFRX-LF) with a coaxil. All system works well without URSP but when i taste with the USRP i get so much noise and the SNR give me -infinite. I checked the problem comes from "uhd ursp sourse" block, that make me think the problem is the noise from URSP. some suggestions?Regards.Lucas.
_______________________________________________
Discuss-gnuradio mailing list
address@hidden
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
_______________________________________________ Discuss-gnuradio mailing list address@hidden https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Prev in Thread] | Current Thread | [Next in Thread] |