Older post tube amp schematics looks something like this:
This schematics and tube amplifier is not designed for tube maniacs. It is designed to test tubes. Resistor’s and capacitor’s values may differ, because I build the amp and only later draw diagram.
V1- 12AX7 (can use 12AU7 or something, when input sygnal is strong), V2- 6ÐŸ14ÐŸ, V3- VR150 (150V zener), R12-200K, C2-0.1Î¼F