> How does tying the grid hard to ground help, apart from
> the profits of the
> tube retailers?
Nonsense about manufacturers being in a conspiricy to make
money really is just a last ditch attempt to appeal to
emotions rather than common sense and good engineering.
Common sense and good engineering dictate any fault
protection for flash-overs be in the HV supply line, not
downstream in a grid.
Protection for excessive drive or RF induced grid current
belongs in the cahode path of a GG amplifier.
The grid is a barrier that protects and isolates the input
from the output, it belongs connected to ground unless there
is a compelling reason to NOT do that and the designer is
willing to accept an increase in input system failures as a
price for floating the grid.
> The fact that the grid "is the first thing in line" is not
> in dispute,
> HV-grid fault current and its duration is.
As I said, protect it at the source. And at least do
something responsible and sensible like using the correct
compoenets, not carbon grid resistors as fuses!
> It seems that you are inferring that a frangible component
> in the grid
> circuit, when subjected serious overload provides no more
> protection than a
> solid strap.
1.) Floating the grid opens a can of worms. We lose the
barrier between HV and cathode.
2.) A carbon resistor is about the strangest thing I've
heard of to use as a fuse to protect sensitive components.
It is horrible engineering.
3.) Universally suggesting people remove overload systems
based on not having even read or understood a schematic is
not helpful to anyone.
There are right ways to do things, and wrong ways. Fusing a
grid is bad enough, using a resistor as a fuse is worse, and
telling people to get rid of real overload protection takes
it all one level lower.
73 Tom
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