Re: 4-1000A Screen Biasing...

["David Trimmell" <davidt-at-pond-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi,

At 05:35 PM 7/28/00 , you wrote:
>Original poster: "Ed Phillips" <evp-at-pacbell-dot-net> 
>
>>>>snip<<<<
>
>	By the way, the use of a triode connection for tetrodes/pentodes has
>been mentioned several times.  Before doing this you should look at the
>tube data sheets carefully to avoid possible disappointment.  For some
>tubes the two grids should be tied together, while for some others the
>screen should be hooked to the plate.  Depends on the grd-screen grid
>amplification factor among other things. Think some guys have used 803's
>in one of these connections, but don't remember if the actual circuit
>was mentioned here.  
>
>>>>snip<<<<<

Yes, I have used two 803's in triode configuration (screen, control,
suppression grids all tied together) this worked well. I also ran it as
spec. using resistors. I got 7" sparks in both configurations.

>
>	For projects such as these your time is the biggest expense.  Nothing
>like honking big power triodes for simplicity and reliability, starting
>out with babies like the 833's and working up to something really
>interesting.
>
>Ed

I completely agree. Triodes are the best route with a VTTC. Something like
a 4-1000A should be used for a Linear or transmitter, or sold, and used the
money to by a large Triode.

Regards,

David Trimmell
www.ChaoticUniverse-dot-com