Excellent Program & Support

iSDR is an excellent software defined receiver (SDR) program, both as a demonstrator of the technology and as a live receiver in its own right when used with your own separately provided radio frequency (RF) front end that converts radio signals to digitized I/Q signals. It covers all the major modes (CW, USB, LSB, AM, FM, and Binaural), provides bandwidth settings appropriate to each mode, and allows use with prerecorded spectrum recordings or live use off the air when connected to an RF front end. It is easy to tune around the display, change modes and bandwidth, and the audio quality is very good. Display choices are spectrum scope (panadapter), waterfall, and audio oscilloscope.

The history of this program shows that it is well supported and enhanced. For example, when it was recently discovered that the signal level for weak signals was a bit too low to be displayed with certain hardware combinations, the program was quickly updated to version 3.3 in about two weeks with a capability to adjust the signal floor. Problem solved!

The developers support site and forums are very helpful, including information about RF front ends, how to use prerecorded spectrum recording files, which Apple devices are supported, and which external hardware works with which Apple device. I use a Griffin iMic (and the Apple Camera Connection Kit USB adapter) with my iPad 2 and a Sonoma Wire Works Guitar Jack 2 (and the free GuitarTone app from iTunes for adjusting settings, including signal level) with my iPhone 4S. iSDR works beautifully with both these hardware setups connected to my Elecraft KX3 portable amateur radio transceiver.

iSDR is fun, useful, and robust. Short wave radio listeners and amateur radio operators will find the program to be very helpful.

73 de WF4Z

JP OConnor - USA about iSDR