This circuit is from an 80's technical newsletter. The circuit can use any general purpose transistor and its power supply can be changed with a resistive divider to use a single 9V battery.
Several types of OSEPP sensor modules can be obtained from Mouser Electronics for Arduino...
Epcos TDK TB2569 Film Capacitor EPCOS / TDK offers through Mouser Electronics are line of film...
This circuit was obtained from a 2005 Linear Technology application manual. The circuit is...