This analog instrument circuit was found in a 1990s William Sheets. The components are common and are only suitable for cars with mechanical switching (platinum).
Closing and opening S1 for a moment to charge the capacitor, the transistor conducts the load. The...
The basic component of this circuit is a general-purpose SCR. The voltage is according to the...
This simple preamplifier was published in Radio Electronics magazine in February 1958. The battery...