As I understand it, the glitch resistor is not supposed to be a fuse. In the
event of a flashover, it is supposed to limit the current so that components
(even the tube) won't be damaged in the time before the primary fuse in the
power supply opens.
I believe that 10 ohms is on the low side and 25 ohms would be better. During
normal operation it will dissipate I**2 * R watts, so 25 or 35 watts should be
adequate. A vitreous enameled resistor is recommended to take the short but
heavy overload in the event of a flashover. Those rectangular wirewound
resistors containing sand are NOT recommended.
Also it's important to have correctly sized primary fuses.
> On 13 Nov 2016, at 03:52, Dick NY1E <firstname.lastname@example.org> wrote:
> My SB220 stopped operating, with no plate current and pegging the grid meter
> after a bright light out of the rear fan grill. It seems an added glitch
> resistor opened, 10 ohm 10 watts doesn't seem big enough. did it do its job
> and sacrifice itself? The resistor looks fine no burns or anything. Should it
> be bigger or keep this size as a fuse?de Dick NY1E
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