Tom,
>On the other hand if the grid in a triode is floated through a
>resistance any HV faults in the tube would be passed right along to
>the filament/cathode circuit, yet that is supposed to be a "good
>idea".
>
>Odd.
You're forgetting that the only HV faults that ever appear are because of
parasitics!
73
Peter G3RZP
> ----------
> From: Tom Rauch[SMTP:w8ji@contesting.com]
> Reply To: W8JI@contesting.com
> Sent: 30 November 2000 12:41
> To: g3sek@ifwtech.com
> Cc: amps@contesting.com
> Subject: Re: SV: [AMPS] SB-220 Glitch Resistor ???
>
>
>
>
> Date sent: Thu, 30 Nov 2000 09:43:08 +0000
> To: amps@contesting.com
> From: "Ian White, G3SEK" <G3SEK@ifwtech.com>
> Send reply to: "Ian White, G3SEK" <g3sek@ifwtech.com>
> Subject: Re: SV: [AMPS] SB-220 Glitch Resistor ???
>
> >
> > Wilbert Knol wrote:
> > >
> > >
> > >> With the glitch R in the negative return, the cathode circuitry may be
> > >> driven to several kV by a B+ to chassis arc.
> > >
> > >Good point.
> > >
> > >I don't like the idea of most of the HT appearing across the filament
> > >transformer secondary...
> > >
> > Does it?
>
> The same fellow who always proclaims a "glitch resistor" in the grid
> is a good idea, now finds fault with a resistor in the B-.
>
> A glitch resistor in the B- only would cause the negative terminal at
> the HV rectifier and filter cap junction to go up towards HV + rail,
> everything on the chassis and cathode side of the resistor could be
> fully clamped to ground and remain so just as a resistor in the HV
> line would allow. It would make no difference at all!!!
>
> On the other hand if the grid in a triode is floated through a
> resistance any HV faults in the tube would be passed right along to
> the filament/cathode circuit, yet that is supposed to be a "good
> idea".
>
> Odd.
>
>
> 73, Tom W8JI
> w8ji@contesting.com
>
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