Quantum Spectrum - a DSP option for SDRs

and maybe ALL radios (someday)

Ham Radio Information 03/11/2023

Posted By: Robert Nickels (ranickels)
Posted on 03/11/2023

The Quantum Spectrum is an add-on DSP that provides real-time spectrum and waterfall display for any SDR providing IQ outputs. This includes the Xiegu G90, uSDX, (tr)uSDX, mCHF, Elecraft, and more and a serial CAT connection allows the radio to be tuned via the touchscreen interface. The 360x240 pixel color touchscreen can provide various tuning/display options and implements a Low-IF architecture to move demodulation away for center 1/f noise which considerably improves performance over the zero-IF method. The company promises audio demodulation and more DSP enhancements in future releases of the firmware, but the unit comes ready to go, although fine-soldering wire connections must be made and the unit presently offered on group buy does not include an enclosure. (Surely a 3D printed one will be available soon).

Most low-cost SDR transceivers use a Taylor or Quadrature Sampling Detector which is capable of quite good performance - much better in most cases than the DSP back-end these radios can provide. Most of them cannot provide a nice color display and touchscreen interface for size and cost reasons, and some of the available solutions are grossly expensive for what they do. At around $100 the Quantum Spectrum appears to be a great addition to the low-cost SDR user's bag of tricks and will be a significant enchancement, especially as new software features are rolled out.

Presently the company is accepting pre-orders for a group buy. The webstore allows placing a 1GPB ($1.14USD) deposit to indicate a desire to buy for late April 2023 delivery. Go to their store website for more information.

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