Re: Battery bias directly to grid



bruce seifried wrote:

> In article <43560898.A0E3655F@xxxxxxxxxxxxxxxxxx>,
> Patrick Turner <info@xxxxxxxxxxxxxxxxxx> wrote:
>
> >snip<
>
> > >
> > > Aha... apparently we *are* talking about different cicuits.
> > >
> > > Until it was changed several days ago, I had been referencing the T39
> > > schematic on this page:
> > >
> > > http://members.lycos.co.uk/fiultra/T39-KISS-300B-Ultrafi-crct.jpg
> > >
> > > I was never able to view the other schematic due to unknown browser
> > > demons, but its description sounded like that of the T39 input biasing
> > > arrangement, which I must say was bizarre, but easily fixable (...and I
> > > happen to believe that a good quality capacitor makes a better capacitor
> > > than a battery).
> > >
> > > Carry on...
> > >
> > > -bruce seifried
> >
> > Both of Andre's circuits which use battery bias either in the grid or cathode
> > circuit
> > are NOT prone to switching transients when the gain is changed.
> >
> > Patrick Turner.
>
> >snip<
>
> goddamn, Patrick, you are one stubborn bloke. Please pay attention.
>
> There are at least *three* versions being discussed, not two:
>
> 1. batteries in the cathode circuit.
> 2. batteries *in series* with the grid.
> 3. batteries *in parallel* with the grid (grid leak position).
>
> Circuit number three is what I have been talking about. The schematic
> was locate at the link I referenced above, until a few days ago, when it
> was redrawn to show the batteries in the cathode circuit. OK?
>
> I will send you a copy of said schematic if you need to see it.
>
> Can we move on now?

For 3 you'd need a cap somewhere.
But Andre sent me what he was discussing, and there was no way you'd get transient
or
biasing problems.

I am happily settled, ain't movin noplace :->

Although Nicole and Kylie have asked me over to the
tropical island they bought
but I said I'd need to bring a physio, chiropractor, therapist,
and there is limited room.....

Patrick Turner.

>
>
> -bruce seifried

.

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