White Noise Generator

legal pad not talking writing back and forth burn all when complete

 

Iron Butterfly, Joan Jett, Judas Priest, Black Sabbath played at concert volume and talkers using sound powered phones like we used when I was Navy in the 60's ?

 

There is one positive proof method and that is "sign language" ,and you can use it any where on the planet even over the internet.

 

Everyone completely naked, and standing at a location 500 yards into dense brush. Alternatively treading water in a lake or the ocean a half mile from shore.