THE YEAR WAS
"A Potent Death Ray Contraption"
Written by S. R. Powell(writer and artist)
Mystery Men Comics
#9 - A professor has perfected a death ray using sound waves. He sends a letter to the government offering it for use and D-13 is sent to "see what it's all about". Foreign agents, of course, want it, too.
Here are the pages I have of it.