Two Stage Amplifier (T340E)

This amplifier circuit is indicated in a tube experiment kit and is powered by only 12 V. The circuit has high impedance input and output.

Monostable with input lock (CB5426E)
This circuit is from an old manual, but can be easily assembled as the integrated one is still...
Blown Fuse Alarm (CB6109E)
We found this circuit in a 1967 Electronic design. However, it can be easily implemented even...
Low input current adder (CB4908E)
This circuit has a 200 kHz bandwidth and a low input current. The circuit is from the 80's, but...