Online IQ Samples

[rheb1026]

Is there someplace online where I can download IQ sample data? I'm looking for like 10 seconds to a minute worth to test out some software demodulation and filtering I'm working on. Ideally I'd like 20m and 40m band, voice and cw. I have an RTL dongle, but the signals I receive are pretty abysmal inside my apartment (and the cheap dongle has so many spurs anyway). I have a decent 2m antenna, but both ham and airband activity is so infrequent that I can never seem to catch much - by the time I click the record button it's gone.

I tried doing some searches online, but couldn't find anything.

[hendorog]

Have you tried ATIS? That transmits most of the time if you are in range. You could take your SDR closer to the signal

[cncjerry]

Look at the SDRsharp site.  It records and reads IQ files.  I think they distribute some as well, maybe with the program.  It's pretty cool as if you record 96khz or even 192khz of bandwidth you can tune around thru it at a later time.  There are sound cards that can record even wider bandwidths with higher sampling rates.

[donmr]

Or fire up gnu-radio and make some (read an audio file).

[cncjerry]

I didn't think of it before, but just about any audio editing software can make an I/Q file.  I used them for testing.  You just use the program to synthesize a sine wave and then use the same program or edit it to offset the sine wave into the second channel by 90 degrees.  Pretty easy.  If you don't have a program, I think Audacity is free on a mac.  There are a lot of others.  If you really get stuck, PM me and I will send you a file with 1000hz stereo I/Q.

[Artlav]

Signal Identification Wiki - http://www.sigidwiki.com/wiki/Signal_Identification_Guide
Many of their examples come with sample IQ files