3-tube receiver 2 (T1603E)

Using known tubes, this receiver was found in a Radio Electronics from 1949. The circuit does not include the power supply.

200 mA LDO (CB1250E)
The circuit shown in the figure consists of a low voltage dropout (LDO) regulator for 200 mA using...
Varicap Variable Frequency Oscillator (CB4587E)
The great advantage of the circuit shown in the figure is that its frequency is controlled by a...
Electric Tool Torque Control (CB20794E)
Found in American documentation from the 1970s, this circuit can be designed based on a modern SCR,...