On Sun, 2 Jun 2019 15:57:22 -0000 (UTC), Cursitor Doom
wrote:


Gentlemen,

What are the typical average/maximum operating temperatures of a full
wave rectifying tube/valve? Is it normal for them to become too hot to
touch after only a minute or two?
I'm talking specifically about the 5Y3GT in this context.

Vacuum Tubes (Valves) work by heating the cathode to "boil off"
electrons. The 5Y3 has a 5v filament that draws 2 Amps. So that's 10
watts even without any current flowing in the plate circuit. So, yes,
I would expect it to get hot quickly.