Touch sensor (CB8723E)

Found in a 90s Popular Electronics, this circuit uses two PLL tone recognizers to trigger by touch an external load.

| Clique na imagem para ampliar |

Intercom LM386 (CB11567E)
This circuit is quite simple to assemble, having been found in a traditional American publication. The...
Oscillator with Frequency Doubler (CB18885E)
This rectangular oscillator produces signals of two frequencies, one double the other. The circuit is...
Quartz PNP Oscillator (CB18933E)
This oscillator can generate signals up to about 10 MHz, depending on the crystal used. The...