Rumble filter (CB6541E)

This turntable filter was found on an 80's Elektor. The circuit makes use of operational features that are easily obtainable today.

| Clique na imagem para ampliar |

4 Levels Digital Voltmeter (CB4375E)
This circuit was found in an English magazine Radio & Electronics Constructor of February 1977....
Simple Symmetric Power Supply (CB11921E)
This symmetrical or dual source without regulation is indicated for the feeding of experimental projects...
28V x 500 mA Shunt regulator (CB8818E)
Found in a 1960s RCA manual, this circuit uses components from the era. For the indicated circuit R1 is...