HDSDR is a freeware Software Defined Radio (SDR) program for Microsoft Windows 2000/XP/Vista/7/8/8.1/10. Typical applications are Radio listening, Ham Radio, SWL, Radio Astronomy, NDB-hunting and Spectrum analysis. HDSDR (former WinradHD) is an advanced version of Winrad, written by Alberto di Bene (I2PHD). Main features:

• separate large spectrum and waterfall display for input and output signals
• RF & AF spectrum and waterfall is optically zoomed to fit window width independently of FFT resolution bandwidth (RBW)
• flexible and efficient usage of the screen area from 640x480 (Netbooks) up to unlimited
• extreme low-speed waterfall - helpful for pattern noise detection or short wave condition monitoring
• AM, ECSS, FM, SSB and CW demodulation
• basic transmit (TX) functionality in modes SSB, AM, FM & CW
• I/Q modulated signal pair for the TX input signal (Microphone) is produced on the TX output
• squelch, noise reduction, noise blanker, adjustable band pass filter, anti-alias filter
• automatic notch filter and up to 10 manual adjustable notch filters
• record and playback RF, IF and AF WAV files with recording scheduler
• Frequency Manager for Eibi, Ham Bands, Radio Bands, User frequency lists
• DDE client for Ham Radio Deluxe, Orbitron, WXtrack, SatPC32 and Wisp (Howto)
• Omni-Rig support (CAT) to control additional hardware
• support for various hardware through Alberto's (I2PHD) ExtIO DLL interface
• ExtIO frequency options for IF-Adapter, Upconverter, Downconverter, Undersampling and calibration
• All HDSDR program options can be stored and loaded per "profile", to ease use of different receivers
• autocorrelation and cepstrum display for demodulated audio
• command line options "-as"(auto start), -fs" (full screen)
• "-swapsw" (swap spectrum/waterfall display), "-p profilename" (profiles)