Re: Grid #2 in ultralinear mode


"mick"
>
> In a 6L6 g1 and g2 are wire spirals wound in the same direction and
> in-line, allowing a straight line through from the cathode, through
> the grids, between the beam-forming plates to the anode.


** Same construction method used in beam tubes and power pentodes like the
EL34 and EL84.

The screen wires are sheltered " down wind " of G1 where electron density is
low.


> I don't know
> about the diameter of the wire used, but it could be an indication of why
> the max g2 dissipation figure given in the spec is quite low.


** Heat radiated from G2 is all collected by the anode anyhow. At least in
UL mode, the AC component of screen current adds to the output power -
unlike pentode mode where it is entirely wasted.


> This form of construction *could* be why 6L6s seem to be quite good when
> triode-connected. In a normal tetrode or pentode the electron stream will
> hit g2 or g3, causing dissipation in those grids. g2 does operate as an
> anode, with the true anode merely being an electron collector.


** Huh ?

" with the true anode merely being an electron collector "

What drivel.



> The 6L6, on
> the other hand, still uses the true anode as the electrons will mostly
> tend to miss g2, and there is no g3 to get in the way.



** Make up your mind.

Compewter geeks........



........ Phil


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