Why is LimeSDR so unreliable

I have been fiddling around with limeSDR past 4 months or so and I still could no figure out how this device exactly works. I managed to demodulate a simple AM signal the first week I got this board and now even that task is so hard to do reliably. For instance let me show you two different plots I got from the receive channel. When the center frequency is not tuned to the carrier frequency correctly, I get rectangles filled with sine as expected. However, when the LO frequency is tuned correctly, I get total garbage !?!?!?!?? The board’s behavior changes every time I turn it on. I am doing all the tasks using LimeSuite API c++ library and as far as I am concerned, it has the most unhelpful examples and documentation out of all the c++ libraries ever created on this earth. Besides all that, there is no place to get help from except this forum. The official support/tutorials/examples are not at all present. Below are the plots I was talking about.

Screen Shot 2021-03-25 at 15.57.01

Screen Shot 2021-03-25 at 15.56.51

Are you cooling the board? If not, you might want to. I have used heat conductive epoxy to adhere small heat sinks to all major ICs & have a fan on the enclosure.
I use 2 Limes set up this way & they are as stable as can be.



Why don’t you first try the LimeSDR with proven software? Simply download the free SDR console V3.
I use it now for more than a year without problems, as a transceiver for the Oscar-100 sattellite.
Quality is constant and the settings are still in it.
In your case put an antenna on it (or a piece of wire) and listen to FM broadcast stations then you now if its working correct.

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Hello, @ugy99, I’m also having an hard time using the limesdr mini for NMR studies. I’m at the moment trying to make a short, simple, RF burst. However, if I can use GNU Radio to do simple task, I want something more precise and with much more control. I decided to use python library but I can’t even send a sine. The documentation are indeed unhelpfull. How did you managed to do it in c++ ?