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.

Optical communication transmitter (CB7849E)
This circuit was found in a 90s American documentation. The circuit uses an LED that can be of a...
Damped Oscillator (NI012E)
Damped sine oscillations can be produced when short pulses are applied to the input of this...
50 W amplifier TDA1514A (CB15371E)
We found this circuit in the Philips integrated circuits manual of 1990. The circuit must be...