>
>
>Richard wrote:
>
>> >
>> >On Mon, 4 Mar 2002 22:02:43 +0000 "Ian White, G3SEK" <G3SEK@ifwtech.com>
>> >writes:
>> >
>> ><snip>
>> >
>> >Hi Ian,
>> >
>> >> Can we identify a specific range of US-made resistors, for the
>> >> record?
>> >
>> > Here are some real pulse rated types... not just ceramics that (may)
>> >happen to survive the event.
>> >
>> > Kanthal Globar (who acquired the Carborundum product line) makes a good
>> >assortment -- their resistors are rated for both pulse voltage and
>> >energy. Take as look at the AS parts.
>> >
>> > Ohmite has a new line that would be suitable for the application with a
>> >pair in series -- look for the AY & AZ prefix
>> >
>> ? To test a glitch resistor, short the HV+ to gnd. [Before doing this
>> test, install suitable glitch diodes across the meters and across the
>> grid current and anode/plate current shunt resistors] The glitch
>> resistor should not exhibit physical damage or a change in R. If the
>> glitch resistor does pass the test, discard it, install two such
>> resistors in series, and repeat the test.
>>
>> - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
>> www.vcnet.com/measures.
>> end
>>
>>
>
>Isn't the idea of a glitch resistor to act as a fuse ? Don't you want it to
>open on a glitch?
>
? When an overloaded glitch resistor is in the process of exploding, a
metal-vapour arc briefly takes place. The V-drop across such an arc is
c. 20 volts. Thus, the arc does not do much to limit peak current flow,
which is/was the primary job of the glitch resistor, With no defined
limit on peak fault current, tube damage is likely.
cheers, Gary
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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