LimeSDR Transmits HF Voice on 20m Using SDRAngel

LIMESDR HF TRANSMIT UPDATE: …Today, for the very first time, I transmitted a LSB voice transmission at 14.0 MHz (yes, I know USB is used on 20m - I only had it setup in LSB for this test, USB is next) in the HF band with the LimeSDR off a small whip antenna I had laying around to get ‘something’ to the front end of my Yaesu FT-857…The power output is shown on the picture at about 6dBm at 14 MHz, so off the whip it’s going to be REAL hard to hear since I have the 857’s antenna is switched out and its not using anything besides coax to hear the Lime off the whip…But the important thing to note is that Edouard’s SDRAngel program IS working (albeit with a significant 6 second delay in audio transmission) with the LimeSDR and transmitting clear voice audio on HF (and with some spectral TX noise that’s apparent as the below-carrier periodic (they repeat a pattern) signals in the picture, too)…you’ll also note that there’s a remnant signal at 30 MHz that is taking part of the power away from the primary transmit signal…It’s a first, folks, and the recipe for decimation and sampling rates are KNOWN now that make the voice transmissions clear…I’m certain in time that Edouard will have this working without the delay soon…I will have a YouTube video link that I will post later, but if you’re on the LimeSDR Facebook page you can watch that video now…More to follow in the days to come - Stay tuned…! 73 de Marty, KN0CK


…And here is the video link from YouTube that I promised for those that do not have access to the LimeSDR Facebook page ---->

PLEASE stay tuned for more as I have it…

Enjoy…! 73 de Marty, KN0cK

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Hello Marty,

glad to see you get it working and thanks for the video. I just opened a ticket for the extremely large delay ( I’ll see how to get this reduced ~6s is clearly annoying.

There are already some fixes to problems you reported (corresponding to tickets #42 and #43) in the v3.5.4 version just released.

Best regards, Edouard.


@F4EXB - Edouard,

Thanks for the recent update and, yes, the SDRAngel application is working REAL well in SSB voice on HF with the delay, but if you can get that reduced to 1/2 second or less (PiHPSDR has a delay in and around 1/2 second to 3/4 second) then that would be great…! I’m not sure if SDRAngel has any affect on the other spectra that is produced when transmit happens, but I do notice that when the application is not transmitting that you can move the frequencies around and there’s no other interference or spurious, but when transmit is activated spurious will appear along with the 30 MHz and tuned frequency signals. Again, I’m not sure this is your issue - it may be a LimeSDR induced issue - but that can be tackled later, and for that matter I’ll take before and after pictures of the issue to you can also see what I’m seeing with this spurious signal issue.

I’ll try your new version this evening and see the results. SDRAngel is by far leading the pack when it comes to transceiver operations on HF with the LimeSDR. I’m real happy with the progress thus far and see A LOT of light at the end of a very long tunnel with the LimeSDR being a building block of a HF/VHF/UHF transceiver solution for Amateur Radio.

More to follow as I have it with the new version, Edouard,

73 de Marty, KN0CK

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Hope you are doing very well today!

I’m a new member to the forum, but ive been browsing for a while and i noticed that you are the Lime SDR amateur radio guy. i’ve gotten a lot of great info from your posts already so thank you!

Im looking for some example code, preferably in C++, that will allow me to send and receive data (ascii, hex, or binary, etc.) over HF, UHF or VHF from lime to lime.

I bought two lime SDRs and got Soapy running in Ubuntu for both. they are hooked up to separate computers.

Got GNU radio running, and the lime drivers. its all working, but i want to get them to talk to each other sending and receiving data.

I would like to use PSK or some variant of PSK

If you dont know of any code offhand maybe you know a program that will do this?

thank you so much man!



I can’t see my limesdr mini with the last sdrangel version . Limesdr mini isn’t recognize . I’m under windows 10 . Limesdr mini is working fine with sdr console V3 dans modified version of cubicsdr

What is the way to use sdrangel with limesdr mini


@HighDesertBeacon - Jamie,

Sorry for the incredibly long delay in getting this back to you - I’m currently on business travel in Chicago this week and next and will also be moving my QTH about 50 miles west of where I reside now, so very busy time for me and everything is in a blur at the moment.

There are examples of transmit and receive in the LimeSuite zip file on Github and, for that matter, the entire SDSRAngel application is open source and very much available for inspection for transmit and receive using the Lime or LimeMini. MANY of the threads on the LimeSDR forum have examples of transmit and receive, too - you’ll just have to root through all of it to get the info you need. But for a quick start, I would highly recommend the LimeSuite examples they provide as a part of the LimeSuite package you download - within that Zip file are examples of setting up for transmit and receive using the LimeSDR (and LimeMini). But don’t disregard the SDRAngel app for some snippets of info on how to transmit and receive using that app, too.

When I get back on familiar ground again, I’ll try to pass along more info as I have it. But thanks for the initial message and welcome to the fold…!

73 de Marty, KN0CK


I would like to first of all thank you for your warm welcome, and eagerness to reach out! I know traveling can be very disorienting, so i appreciate you took the time.

While your there, try a real deal Chicago hot dog if you get the chance, theres nothing like it!

I’m impressed by this SDR Angel at first glance! i cant believe i didn’t see it before. seems like there’s plenty of functionality from a quick look at the github.

i followed this link for the downloads:

im gonna instal this on my Ubuntu box and give it a try. I also have a windows machine i can use with the other lime in case i run into any snags. I guess it runs windows , linux, didnt see mac os.

As far as the LimeSuite i have played around with the GIU portion extensively in the past but i have not found any rend/receive options for voice or data, within the GUI itself that is. I may have missed it, there are so many options. it is a pandoras box for sure.

Within the LimeSuite example code on github i found this today, which is new to me:

it is a very minimalistic it is a simple rx and tx example that i think i could easily chop up into a send receive routine between my two Limes. I noticed from the #includes that it isnt calling Soapy. it seems to be bypassing soapy and going straight for the driver. is this correct? this is interesting! So ill give that a shot as well!

Again thank you for the guidance. I’ll let you know how it goes back here on the forum.
May you have traveling Mercies, and bon voyage!


Ah, so this is really aimed at system developers and debugging. Most people shouldn’t have to ever use this.

That’s right, this uses the underlying LMS API. For general experimentation I’d probably recommend using GNU Radio with the gr-limesdr source/sink blocks.


I hope this finds you well!
I am trying at the moment to install SDRAngel on my Ubuntu machine.
I am running Ubuntu 16.04.

( from sdrAngel/releases page: sdrangel_3.14.7-1_amd64_xenial.deb
Debian package for Intel/AMD 64 bit architecture with SSE 4.1 support. Works in Ubuntu 16.04)

After i download ed the package sdrangel_3.14.7-1_amd64_xenial.deb

i ran:

sudo dpkg -i sdrangel_3.14.7-1_amd64_xenial.deb

i got:

:~/Downloads$ sudo dpkg -i sdrangel_3.14.7-1_amd64_xenial.deb

Selecting previously unselected package sdrangel.
(Reading database … 335272 files and directories currently installed.)
Preparing to unpack sdrangel_3.14.7-1_amd64_xenial.deb …
Unpacking sdrangel (3.14.7-1) …
dpkg: dependency problems prevent configuration of sdrangel:
sdrangel depends on libopencv-dev; however:
Package libopencv-dev is not installed.
sdrangel depends on libavcodec-dev; however:
Package libavcodec-dev is not installed.
sdrangel depends on libavformat-dev; however:
Package libavformat-dev is not installed.
sdrangel depends on libopencv-highgui2.4v5; however:
Package libopencv-highgui2.4v5 is not installed.

dpkg: error processing package sdrangel (–install):
dependency problems - leaving unconfigured
Processing triggers for libc-bin (2.23-0ubuntu10) …
Errors were encountered while processing:

Apparently there are a bunch of unsatisfied dependencies that are mucking up my installation.
How would i satisfy these?

I tried apt-get on them one by one, but it snowballed into a bigger mess.

Is there a way to do a bulk install?

Do you know of any installation tutorials for SDRAngel?

Haha…why am i even using Ubuntu!? Seems like everyone around here is rocking Debian. Maybe i should just switch to Debian

Thank you!


@HighDesertBeacon - Jaime,

Please review the link here as to the sequence of steps you take to build an Ubuntu installation error-free for LimeSDR / LimeSDR-Mini:

Look though that thread and start over using this guide - THERE IS a absolute series of steps that you must take to make the installation work properly, so that information is in that link. Follow it for any Ubuntu distro and you’ll be fine. Looks like you will have to install Ubuntu clean again and build with that procedure.

Let us know how it works for you - 73 de Marty, KN0CK

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