PowerRF Testing

Formerly PowerSDR

A spectrum and waterfall receiver in the spirit of SDR++, written from scratch for Leopard.

SDR++ can't run on Mac OS X 10.5, so this is a native rebuild of the idea in Objective-C and C: a live spectrum, a scrolling waterfall and the usual demodulators, light enough to leave most of a dual G5 free.

PowerRF showing the FM broadcast band around 105.9 MHz with a spectrum trace and a dense waterfall

PowerRF 0.3.1 on 105.9 FM, live with the dongle.

Features

Spectrum and waterfall with zoom, hover readout and peak markers
WFM, NFM, AM, USB, LSB and CW
Recorder and frequency bookmarks
Hardware and software AGC; Bias-T on by default for the Blog V4

Details

Version	0.3.1, in testing
Runs on	Mac OS X 10.5 Leopard, PowerPC G5 and Intel (universal)
Needs	An RTL-SDR dongle (Blog V4 / R828D tested)

Download

Coming soon. Check back here, or watch tdtech.org/projects.

PowerRF tuned to NOAA weather radio in narrow FM, with peak markers on the active signals

NOAA weather radio in NFM, with peak markers.

This is the plain version of tdtech.org for older computers (no scripts, works over plain HTTP). On a modern browser, use https://tdtech.org/. Updated October 2026.