LimeSDR Mini "unstable" or "jumping" noise floor and heat issue

Hi everyone. First thing I want to say that I’m total newbie in SDR things. Second thing, english is not my native. Sorry for possible mistakes.
So, recently I got my LimeSDR Mini, installed FTD3XXDriver, Pothos and SDR Console V3 (I have win 7 on desktop, win 8.1 on laptop). And for the test I decided to listen to FM stations.
Two problems begin here.
First one is about the “jumping” or “unstable” noise floor (across all frequencies). There is no matter if antenna connected or not (I’m using cheap chinese antenna from nRF24l01. Just I don’t have anything better for now). Values of LNA, TIA, and PGA doen’t matter too. Also doesn’t matter that if I use desktop PC or laptop (in different rooms in flat). I’m able to listen to nearest FM stations through that noise, but sound quality is bad. I’ll attach screenshots of SDR Console V3 screenshots of that noise.
Second is about the temperature of the board. LimeSDR becomes really hot on touch after 7-10 minutes of operating. Is it okay? What is the normal operation temperature for LimeSDR Mini?

And photos of the board. Maybe there is something wrong?

I have tested two LimeSDR mini’s ( Side by Side Comparison of two LimeSDR Mini’s ) and found one of them shows the same behaviour using SDR Console as to what you have described, whilst the other seems to work perfectly all the time.
I have then done some testing with HDSDR and both the LimeSDR mini and they both seem to work fine, so I would suggest you give HDSDR a go and see if your LimeSDR mini works better. Search this website for information about setting up HDSDR using ExtIO to connect to your LimeSDR.
Have not yet been able to explain why the two units behave differently to each other with the same installation of SDR Console.

Hope this helps

I recently has started experimenting with “mini” and also have similar issues with output at SDR console.

  1. I am more or less confident that device is working properly. Passed all tests from test-client!AsTX3WCH_RLChkcEP2wP-RhKL8a0 and recognized by SDR console. Try this tool first
  2. You have mentioned that installed driver FTD 3xx, but I have FT 601. Quick search shows that there is also specific driver Don’t know if it suits for “mini”, because haven’t tried yet.
  3. I have started from minimal sample rate, i.e. 2,5MS/s and heard no sound at all for WFM stations though console showed perfect match and different filters I have applied didn’t change the picture. Then I have started to increase device sample rate and near 10MS/s I started to hear noise from the speakers. At 15MS/s I could even distinguish speech, but quality of the sound is still awful. I can’t understand why. Using RTL SDR with it’s 2,4MS/s speech quality is nearly perfect!

My device also gets hot when working, but probably it is normal behavior. Try to measure temperature with LimeSuite. My shows 53C. Default is 51C when it is just turned on and it is hard to believe it is correct.

Will continue to experiment, but with such a number of parameters it is hard to guess where problem could be. If you find something, please let us know.

Tried with HDSDR. Here what I got.

FM stations are audible.
LimeSDR temperature was a little lower on touch.

vadim, I know about this testing software and my LimeSDR Mini passed it tests too.
As far as I know this driver is not for Mini.
And about the “Read Temp” button in Lime Suite GUI. I had found that is temperature sensor in unpopulated. So it turns out that these readings are not true.
You may try to check temperature through Modules > Board controls > Labes > LimeSDR Mini and click Read all. In my case it shows -1.
Here should be that IC that measures temperature.

I have same problem! Limesdr mini, 88-108 mhz with sdr console audio not is clear, jumping and if I increase Bandwidth not work (( Cubic SDR work only with default Bandwidth bad of a RTL (