This is a different circuit for a component from the past, the zirconium arc lamp used in projectors. The circuit is from an August 1972 Radio Electronics magazine.
Found in a 90s Popular Electronics, this circuit uses two PLL tone recognizers to trigger by touch an...
This Hughes circuit is from 1968. Equivalent modern components can be used. The input impedance is...
This circuit is from 1995 documentation. In the original, the source is symmetrical at 12 V, but...