Power source for tubes (T384E)

This experimental bench source was found in a modern book on tubes. The components used can be easily obtained.

Video driver with impedance matching (CB20915E)
In this circuit of an old American documentation, the input impedance is the same as the output...
Voltage Level Detector (CB16801E)
This circuit of old documentation is based on an operational amplifier that is no longer used...
Temperature to Frequency Converter LM35 or LM34 (CB25447E)
We found this circuit in the March 1992 Radio Electronics magazine. The circuit provides 100 Hz...