Re: Filament voltages

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>" <davep-at-quik-dot-com>



Tesla list wrote:

> Original poster: "Alexander Rice by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <alex-at-rices.myip-dot-org>
 
> 06/05/2002 18:58:21, "Tesla list" 
> <tesla-at-pupman-dot-com> wrote:
 
>>Original poster: "davep by way of Terry Fritz 

> <twftesla-at-qwest-dot-net>" <davep-at-quik-dot-com>

> Hi Dave

[snippage]


>>>so a 3kw fil trans will provide a good 
>>> transformer.

>>>	I'm in favour of over design, but 1600W 
>>> is 1600W.


> my understnding is that since the filament 
> provides the electrons by thermionic emission 
> then the power that is being drawn from the 
> tubes mostly comes from the plate,


	Completely comes from the plate supply.

> the accelerating voltage is applied to the plate 
> and the control voltage to the screen. So in
> this case you need more than just the apparent 
> power for the resistive load of the fillament


	Indeed.  that is needed in the PLATE supply.
	The anode (filament) could care less
	were the heat comes from.  Gas jet or oil
	burner would work.  (OK OK:  Not Practical).
	Filament power heats the filament.  Plate power
	(to do useful work elsewhere) comes from the
	plate (aka B+) supply.


	best
	dwp