Touch switch (CB8727E)

Found in a 90s Popular Electronics, this touch switch uses a single sensor. PLLs are common today. Observe the supply voltage range.

| Clique na imagem para ampliar |

Audio Leveler (CB6481E)
This circuit was found in an Experimenters Handbook of the 1990s. The purpose of this circuit is to...
49 MHz Receiver (CB18072E)
Signals from old cordless phones can be picked up with this circuit. L1 has 10 to 20 turns of 32...
Series LC Oscillator (CB24027E)
This emitter-coupled transistor LC oscillator circuit was found in the May 1970 issue of Radio...