Pre selector with varicap tuning (CB9172E)

This circuit for the medium wave range was suggested by a Popular Electronics from the 90s. The double port MOSFET is an unusual component today.

| Clique na imagem para ampliar |

Very High Voltage generator (CB15714E)
This circuit generates voltages of tens of thousands of volts for projects such as electrostatic filters...
Resistor voltage control (CB20758E)
This circuit was found in an old American documentation. The operational used is of the...
NiCad Charger (CB15654E)
Rechargeable Nicad batteries type AA, C or D can be recharged with this circuit, which is nothing...