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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