The LimeSDR can now tune to HF Frequencies

Back in June the LimeSDR completed its $500,000 crowd funding goal. The units are still in production and have not yet shipped, but the software is currently being worked on heavily. In a recent update they have enabled HF reception on the LimeSDR hardware. LimeSDR beta tester Marty Wittrock wrote in to let us know his review of the new update:

Another major step forward for the LimeSDR yesterday…

As a part of the continuing development of the PPAs for Ubuntu and other distros, the LimeSDR is now supported for native HF tuning – – no transverter required. Receive has been functionally tested from 7.0 MHz to 56 MHz and even with the matching networks as they are in the LimeSDR I have (which is not what will be delivered in November – the LimeSDRs the backers will receive in November will have modified matching networks to be more broadband and perform better than what I have right now) the receive quality was very good with my applied HF station antenna (ground mounted vertical for 80m – 6m). I shot two videos yesterday of the LimeSDR operating on the 20m band – one with USB voice and one with CW/RTTY on the contest weekend for RTTY (REAL active). I ran this completely from a USB 3.0 Flash Drive plugged into a Dell 3020 and booted from that Flash Drive to operate the LimeSDR. The Flash Drive is loaded with Ubuntu Xenial (16.04), all the applied support files (SoapySDR, GNURadio, OsmoSDR. etc) and the application GQRX to tune and demodulate the LimeSDR. The setup worked VERY well and the results can be viewed with the two videos provided here:

20m Phone Using the LimeSDR in Native HF Tuning Mode Receive
20m CW and RTTY Using the LimeSDR in Native HF Tuning Mode Receive

Again, I was impressed with the quality of the direct, native, HF tuning of the recent updates to LimeSuite. Having this functionality in LimeSuite finalizes for receive, but I still need to check out the transmit. It’s my hope that Simon Brown’s SDR Console V3.0 will update with the new HF tuning improvements such that I can use his app on Windows to do a full checkout in receive/transmit with the LimeSDR and hopefully apply it to the WSPR app to have the LimeSDR operate HF digital modes on the HF band and Amateur Radio frequencies to have the first true LimeSDR operation benchmark.

I fully intend to have Flash Drive images available for download once I put the final touches on the Flash Drive I have. This will allow all Hams that want an instant solution for booting Ubuntu and running GQRX for receive to use their LimeSDRs right out of the chute without having to install ANYTHING provided that they have a PC that is decently fast (3.0 GHz, 8GB RAM) and has USB 3.0 ports on the PC. I’m looking for a reliable means to read/write the Flash Image and then take the image and ‘burn’ other USB 3.0 Flash Drives with the image. Once I have that reliably working, I’ll post the image and the Flash Drive app so ANYONE can make their own from a blank 32GB to 128GB Flash Drive.

More to follow on the HF transmit as I have those apps and check that out – – Stay tuned..!

The LimeSDR is a RX/TX capable SDR with a 100 kHz – 3.8 GHz frequency range, 12-bit ADC and 61.44 MHz bandwidth. It costs $299 USD.


  1. AD5NL

    What sort of antenna is being used? I assume this is an external, probably a dipole?

    Looking forward to limesdr ship day! Guess I better go find me some U.FL to SMA pigtails (looks like Mouser and Amazon both sell these).

    • Marty Wittrock

      AD5NL – The LimeSDR operating in Native HF was using a ground-mounted Hustler 6BTV – has great performance over 80 – 10m and pretty much a pretty nice ‘coat-hanger’ for 6m.

      • AD5NL

        Okeydokey! Rough look at this indicates its a trap vertical. So probably decent SWRs although maybe a little lossy. Seems like this’ll be a great performer with a full dipole, G5RV, etc.

Post a comment

You may use the following HTML:
<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

This site uses Akismet to reduce spam. Learn how your comment data is processed.