Basic treatment of voice with csound algorithm
Distorted CQ request for a ham operator. http://en.wikipedia.org/wiki/CQ_%28call%29 (thx to @Speedenza)
Unknow (for me) radio signal. Any ham radio expert in the room?
Another RTTY radio signal (thx @speedenza)
RTTY transmission sound http://en.wikipedia.org/wiki/Radioteletype (thx @Speedenza)
Playing with modulation of radio signal (similar sonority with martenot waves) and finally slow reception of a regular station (Radio ...
Probably another jamming radio station
Modified beat frequency by ssb modulation
Strong radio jamming signal http://en.wikipedia.org/wiki/Radio_jamming (thx @Trebblofang)
Regular radio station (turkish?) listen through a SSB filter
Powerful interference modified randomly varying the SSB filter of my receiver