This 50% duty cycle configuration was found in a Popular Electronics from the 1990s. The operating frequency is given by C1.
This circuit is from a 1979 publication. The sensor consists of plates or screens that, when...
Found in an 80's documentation this circuit uses an integrated from the uncommon era today. Other...
This circuit was found in a Popular Electronics from the 90s. It uses a LASCR which is a photo-SCR...