Fast Heating 15W Amplifier (T487E)

We found this circuit in an American documentation from 1947. The circuit uses 5 tubes and has a feature to keep the tube filaments preheated.

| Clique na imagem para ampliar |

Courtesy Light Expander (CB4958E)
This circuit keeps the courtesy lights of a car on for a while after the doors are closed. The...
Continuity tester (CB9326E)
This circuit was obtained in an Electronics Now from the 90s. The circuit uses operational...
VHF Amplifier (CB3886E)
This circuit was originally designed to measure the gain of two-door RF MOSFETs as indicated by...