Programmable Twin T Band Pass Filter (CB6244E)

This circuit was found in an American 1980s documentation. Dual FETs can be replaced by single equivalents. Control voltage ranges from 0 to 1 V.

| Clique na imagem para ampliar |

Broadcasting band amplifier (CB8404E)
Found in a 90s R-E Experimenters Handbook, this circuit amplifies signals from 100 Hz to 3 MHz....
LM324 Electret Microphone Amplifier (CB4838E)
The gain of this amplifier is given by the 120k resistor, which can be changed depending on the...
Robot eyes (CB7262E)
This sensor circuit for a small robot was found in a Popular Electronics from the 90s. The circuit...