-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
Behalf Of Chris Howard
>> Fuses and especially resistors are significantly less
>> reliable than electronic overload circuits for soft faults,
>> and hard faults should be handeled in the anode.
>Well... the other issue of course is _COST_. If a reliable
>system is obtainable without investing in a sophisticated circuit
>that's a good reason to stick with the simpler method.
There is neither high cost nor a sophisticated circuit necessary to protect
tubes.
The cost is always a fraction of the tubes value
>As for "hard faults should be handled in the anode",
>I parse that statement as being a design philosophy.
It is the only way.
>(by Hard Fault do you mean arc? I think so.)
>Well here we get to a minor point of contention.
>The textbooks we've been examining, with your generous help,
>don't cover what happens when a grid under arc is floated.
>So... we don't have good data on what happens, except for
>the experience of folks who say things work out ok.
When the grid is under arc it is at anode potential so another arcing path
to the cathode showing up is more then likely if it is not grounded.
There will be a big chance for transceiver damage then among melted cathode
circuitry.
>If it were dangerous to the tube.. I would think the experience
>stories would be different than what has been reported here.
It depends on the mechanical layout of the tube and the anode voltage level
>Or, maybe the position of the pro-fused-grid bunch would be
>that arcing is less likely with a fused grid altogether...
>I'm a little shakey on this point.
Arcing occurs independent of the grid to ground path
73
Peter
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