>
>Rich, Ian & all...
>
>Am I missing something? There's no reason for the cathode and bias circuit
>to go way negative when the "glitch resistor" is in the negative HV lead
>and a +HV arc occurs.
>
>Putting the resistor in the negative lead means only that the -HV POWER
>SUPPLY SIDE of the resistor goes to ~full -HV during a +HV short or arc to
>ground. The cathode side of the resistor should be at or close to ground
>potential for negative voltage, so that the full HV drops across the
>resistor.
? good point, Dick. However, the problem of additionally insulating the
neg. HV circuit is obviated by putting the glitch-R in the positive HV
lead -- as is recommended by numerous power grid tube manufacturers. .
. In the Henry Radio 3-500Z amplifiers that have a glitch-R in the neg.
lead, I have heard of many instances of grid-fil shorts occuring during a
big-bang. .
>
- cheers
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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