An rtl_tcp compatible server for the LimeSDR Mini

I recently acquired a new LimeSDR Mini USB SDR module. In order to test the receive function of the LimeSDR Mini using my existing SDR applications, I wrote an rtl_tcp compatible IQ server for the Mini. I’ve posted the source code to my lmm_tcp server on GitHub:

Using the lmm_tcp server, I can the plug my LimeSDR Mini into a Raspberry Pi 3, then view an RF waterfall and listen to demodulated audio on my iPhone or iPad, using either my rtl_tcp SDR iOS app, or the SDR Receiver iOS app.


@hotpaw2 - Ron,

Welcome to the forum…! Great work on that app - looks wonderful. Does the app on the Pi support the GUI, too? I don’t have an iPhone (I’m on Android) and I’d like to give this a spin. Let us all know what’s possible using your app.

73 de Marty, KN0CK

The iPhone does not have a USB port, and Apple restricts what devices can be plugged into their Lightning connector. So the strategy I use for USB SDR devices is to plug them into a tiny inexpensive computer, such as a Raspberry Pi, and stream the raw IQ data from the USB SDR over the network to my iPhone for signal processing, visualization, and demodulation. The rtl_tcp server protocol serves IQ data in exactly the manner needed for RTL-SDR devices. The code I posted on GitHub is a work-alike server for the LimeSDR Mini (perhaps it works with a LimeSDR as well, but I haven’t tested that as I don’t have one), so that I can use my RTL-SDR apps on my iPhone with the Lime plugged into a Pi.

On the iPhone (or iPad), there are 2 iOS apps that can take in raw IQ data and visualize/demodulate etc. One is mine:

and one was done by an amateur radio friend of mine:

IIRC, there are already several Android apps in Google’s Play store that can work with rtl_tcp , but I haven’t tried any of them, as I don’t have an Android phone.

73 de Ron, N6YWU

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