Thank you to Stefan Dambeck (DC7DS) for submitting news about OpenWebRX adding support for Hermes HPSDR compatible SDRs. Hermes is a single board version of the open source high performance SDR (HPSDR) design. There are several compatible Hermes designs including the newer Hermes-Lite 2 . The Red Pitaya is an open source electronics laboratory instrument, but custom software can be installed allowing it to function as an HPSDR type SDR. OpenWebRX is software which allows you to access your SDR remotely via the internet or local network through a web browser. Stefan notes:
I built a test setup today using a Red Pitaya 125-14 SDR in HPSDR mode, and this is now also supported, see screenshot.
At the moment, only one receive stream is supported, for the red pitaya with 192KHz bandwidth.
The SDR is advertised to cover HF + 6m (50MHz) and includes two 16 bit 50 ohm input ADCs and two 14 bit outputs. Based on the Xililinx Zynq 7020 FPGA running an ARM cortex A9 processor it’s plenty powerful to handle the various modes frequently seen in the amateur bands and then some while supporting an impressive 122.88 MS/s sample rate.
This hardware is also fully compatible with the HPSDR software platform which is an open source project for amateur radio SDR operation.
While this radio is built with amateur operation in mind, it is still a very capable platform that could be used for experimentation albeit with a more restricted frequency range that what you may be used to with traditional software defined radios.
The radio retails for $499 euros and will be available for pre-order from RedPitaya until March 31st of 2019.
The Red Pitaya is a type of advanced digital acquisition device (DAQ) that is marketed mainly for use as a type of digital oscilloscope. But it has an on board programmable FPGA and through various downloadable apps can be used for many different applications, such as a spectrum analyzer, impedance analyzer, bode plotter, signal generator or even as a software defined radio.
Recently, Dave from the hugely popular electronics YouTube show EEVBlog reviewed the Red Pitaya. Whilst Dave doesn’t try out the SDR apps, he tests it out as an oscilloscope and also tests more of its default apps such as the spectrum analyzer.
Unfortunately in his review the Red Pitaya does not seem to live up to expectations. During operation Dave encounters problems with the WiFi connectivity, frequent problems with the web based apps crashing and freezing on him, and discovers that the provided apps are extremely rudimentary and provide very little functionality. He mentions that the device is probably more useful for people wanting to write their own customs apps for specific applications, but as an out of the box digital measurement tool it is not there yet.
The Red Pitaya is marketed as a type of digital oscilloscope, and is more accurately described as a type of digital measurement and control tool that sells for about $220 USD. However the technology behind its operation (high speed ADCs) is basically the same as what is used in a software defined radio like the RTL-SDR. By using the correct software, and by reconfiguring it’s onboard Xilinx FPGA, the Red Pitya can be turned into an SDR transceiver.