You need a TVS diode because many voltage regulators do not have the ability to sink current, nor can they respond fast ...

with the 1930s invention by the Russian [Oleg Losev] of an early form of tunnel diode. But there’s an earlier amplifier technology that used a solid state circuit which is largely forgotten ...

Using a few simple formulas you can then calculate how much noise the amplifier produced ... to go for the classic method of using a vacuum diode. He describes the design and analysis of a ...