How do I make a crystal microphone element? Simular to the Astatic
MC-151 or a ceramic microphone element simular to the Astatic Mc -127.
Also there is a crystal made by Sure , it is the 707 model element The
elments were first manufactured in the 40's or 50's and the Astatic's
just discontinued. So I know the technology cant be that bad. Astatic
and Sure both  quit making OEM replacement elements. I am very
interested in any information that would lead me to the developement
and possible sale of these replacement elements.

Thank You 
Al Hostert