[Amps] "Tubes 201" - How Vacuum Tubes Really Work

[Peter Chadwick]

Rich said;
>> However, 'flashovers' in high power tubes with a good vacuum have 
> been written up many times over the years, with a number of 
> explanations. In tube manufacturing circles, they were said to be 
> 'barnacles', and could be removed by controlled energy flashovers - 
> there was an article in about 1934 in the IEE journal. As I recall, 
> flashovers are more prevalent with new tubes.
> Sorry, I just don't buy grid fuses ( and even more so, resistors as 
> fuses) as a good idea. I believe I'm not the only one, though.

Definitely not, Mr. Chadwick. <
Definitely not what? That I'm the only one who doesn't buy the idea of grid fuses as bad idea? That there are published articles that have been around for years about flash overs?

Then Rich said:
>Do you subscribe to the statement that  
the R of a Ni-Cr conductor decreases as frequency increases? -- i.  
e., that it exhibits reverse skin-effect<
No, but I fail to see any connection between that and the previous discussion.
I would comment that it's perfectly possible for a component made from a nichrome (or any other) conductor to show a decreasing impedance with frequency above some frequency if it is so constructed that the self capacitance is high enough to have a lower reactance than the inductance plus its series resistance.
73
Peter G3RZP