DSP-RDF Doppler Radio Direction Finder Kit

DSP-RDF Doppler Radio Direction Finder Kit


This kit is based upon the N0GSG DSP Doppler featured in the November 2002 QST Magazine. Doppler RDF units determine the bearing to a signal's source by electronically rotating four antennas, arranged in a circular pattern, at a high rate of speed. The signals received at each antenna are combined and passed on to your FM receiver which is tuned to the frequency of interest. The FM receiver detects the incoming signal and produces an audio tone which is then passed back to the Doppler unit. Inside the Doppler unit are two microprocessors which control the antenna switching and process the audio tone, from the receiver, using DSP techniques. The result of this processing determines the relative direction to the signal source. The direction is displayed continuously in real-time on a circular array of 16 LEDs, each representing 22-1/2 degrees of angle. In the case of intermittent signals the microprocessors save and display the last directional information (shown as a flashing bearing indicator) until the signal is again active. Active signals are displayed as a steady directional indication. The DSP-RDF Doppler kit being offered by W6DFW incorporates another feature not in the original design. This feature allows direction finding of a jamming signal even when the jammer is broadcasting a tone intended to interfere with Doppler units.


http://www.byonics.com/dsp-rdf/