Has support for using the LimeMini on HF improved yet?

[chibill]

I originally tried using my LimeMini for HF shortly after I got it back into 2019 and there was little support in software and the ones that did had many bugs. Also I learned the you have to actively cool a LimeMini to use it on HF otherwise the thermal Nosie swamps out everything. (Meaning heatsink plus a fan.)

What’s the state of things in what supports the LimeMini and what doesn’t as I literally haven’t touched mine since before the pandemic.

I am also interested in learning if anyone else has had this thermal noise issue.

[AA7QQ]

I think SDR Console has support for HF on the Mini now.

Ed

[yt7pwr]

Not yet finished but it is working on HF, Windows 64bit application. Link:
https://drive.google.com/file/d/1hvuDEhC1Vl1MqgDU2pfuKxatMpMyKvsU/view?usp=sharing
Unpack into empty folder and run LimeSDR#.exe

[frog]

LimeSDR-mini: What needs to be cooled and to what temp?

I’ve changed the title and content of the original post, which was about my LimeSDR mini not receiving below 31mhz when the temperature of the LimeSDR mini as measured on Lime Suite was above 45C. After more experimentation, it appears that the temperature readout of LimeSuite doesn’t really make sense to me. At a measured temperature of 45C in LimeSuite, a FLIR infrared camera measuring the temperature of the FT601 and Altera FPGA chips puts the surface temperature of the IC’s at approximately…

The heat issue from my experimentation is not “thermal noise”. If it was thermal noise, then the SNR would decrease linearly with board temp. YT7PWR has a good explanation related the LO.

Below 30Mhz on LimeSDR Mini - Full of garbage

Just change freq to HF. Set sample rate to 1536, LPF to 40MHz and you can receive down to 5.5MHz. For entire HF increase sample rate and LPF (but you need to change RF input of Mini). Also, use GFIR as band filter (set to 0.4 for 20m for example).

LimeSDR-mini bellow 30MHz

I testing my new LimeSDR-mini. I testing with CubicSDR and Console v3. With Console v3 and CubicSDR v0.2.3 working stable but not with newer versions. I tried to receive signals from 10 MHz, but any signal on screen. If I tested with signal generator, then I could see that the receiver started to work just above 30 MHz. I think LO does not work. Can it be changed on settlements or my equipment is bad? Joe

My suggestion is that if you need HF operation, to either cool the limesdr mini passively or actively, or buy another product which is designed specifically to receive HF.

[chibill]

I assumed it was thermal noise in mine since when running HF the temperature would slowly creep up toward 50c and as it did so the SNR of the bands would greatly degrade unless I cooled it.

And yea that thread that YT7PWR was explaining it to me in was my last attempt at HF were I discovered you need to actively cool it for any good performance below the FM broadcast band.

I still have trouble wrapping my head around the NCO and how it’s used. Considering its not like say the normal idea of just a up converter, and it also depends on the sample rate what the NCO can be set to. (At least it did back when I made that thread.)