Found in a 1964 Electronic Design, this circuit makes use of FETs of the time. These transistors can be replaced by modern general-purpose types. The input resistance is 30 M.
This circuit uses the Linear Technology LT6505 and was found in a 2005 manual. The circuit is for 24 V...
The tone produced by this circuit depends on the capacitor and the adjustment of the...
Equivalent triacs and any diac may be used in this circuit of the 1977 GE semiconductor manual. The...