This circuit only works with incandescent lamps and the frequency is adjusted in the pot, depending also on the capacitor. The triac must be equipped with a heat sink. The circuit is from an 80s manual.
This sensor circuit from a 1967 Ferranti documentation uses components from the era. The circuit...
This is the receiver for the previous circuit transmitter. Similarly, no information about the...
Found in a 90s Popular Electronics, this circuit uses two PLL tone recognizers to trigger by touch an...