Low-cost instrument is a tough price test for the high-end makers

The sizeable capital investment involved when it comes to buying top-end oscilloscopes, logic and signal analysers can have even the toughest of bean-counters snapping shut their corporate wallets.

But this may no longer be quite the financial threat it has been in the past thanks to some smart low-cost test and measurement thinking by a small, privately owned Slovenian company.

Called Red Pitaya and established in 2013, it has set about changing the test and measurement (T&M) world by developing a credit card sized, multi-functional, open-sourced and reconfigurable instrument that is clearly positioned as a low-cost alternative to much more expensive measurement and control instruments.

I met the CEO of the company, Rok Mesar, recently in London and he summarised his company’s product called STEMlab as the T&M equivalent of the Swiss army knife for engineers, a multi-tasking tool that is not only modestly priced but is aimed at both the big corporate engineers and students alike.

STEMlab is based on a dual core ARM Cortex A9 + Xilinx Zynq 7010 FPGA SoC which has a dual core processor and FPGA logic. This facilitates soft and hardware programming and is coupled with accurate ADCs. Customisable at the FPGA and CPU levels, STEMlab can process real-world signals. The product’s board has front-end input and output connectors that feature a curved design making it as small as possible and eliminating the need for other adapter boards.

STEMlab can function as an oscilloscope, logic analyser, signal generator and spectrum analyser.

To run vector analyser applications (VNA) users need STEMlab plus an additional VNA bridge module. VNA runs on Windows and Linux and covers a frequency of 500kHz to 62MHz It has a directivity of 42dB, a dynamic range of 74dB and a noise floor of 88dBm.

Software features include. plot formats (Smith chart, impedance, SWR, reference coefficient, return loss), open, short and load calibration modes, measurement export and marker readouts. Included in the VNA module box are an RF SWR bridge module in an aluminium enclosure, calibration accessories (50 Ohm, open & short load) and cables.

With high-end ‘scopes often costing up to €20k Red Pitaya has come up with a price-challenging alternative but it’s only realistic to say that these days along with the very expensive T&M gear there are also plenty of test options that are competitively priced.