Re: Ross-O's VTTC update

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

Original poster: "David Trimmell by way of Terry Fritz <twftesla-at-uswest-dot-net>" <davidt-at-pond-dot-net>

Ross,

Your Grid leak setup probibly needs a tighter coupling with the Primary, O
R? No wonder you had to back off from the primary! Good thing you added
current monitoring. The grid is really a ballance of proper coupling too
best (safe) current/ voltage. With no R you may be pushing the voltage
limit of the grid. You don't want to run this as grounded grid service. I
ahve noticed that one can get great performance with very low grid R, but
it will be short lasting, as the tube will probibly blow up.

"I" would not go bellow 2000 ohm's in the grid leak (with multiple 833's I
have found 8 to 15K too be best, but this depends on tube type), and I
would adjust coupling (more/less turns and distance from Pri) with higher
grid R. This is a very complex dance! I am glad you are do such a good job
measuring and documenting this process.

Regards,

David Trimmell
www.ChaoticUniverse-dot-com


On Mon, 22 Jan 2001, Tesla list wrote:

> Original poster: "Ross Overstreet by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <ross-o-at-mindspring-dot-com>
> 
> Hi Guys,
> Added more stuff to the page.  http://users.better-dot-org/roverstreet/  then
> click on "tube coil"
> 
> Of particular interest is:
> (1) 3 new pics of the coil in action.  Be sure and look at "helix_arc.jpg".
> (2) a bunch of new measurements
> (3) performance data with the reworked primary and grid coil
> (4) link to http://frank.nostalgiaair-dot-org that has incredible original EIMAC
> PDF data sheets.
> 
> Need to figure out:
> (1) grid circuit still not optimal.  I(g) is looking more reasonable but the
> coil still won't run good unless I completely short the grid leak C.  See
> page for more details.
> 
> (2) I played around a bit with calculating the sideband freqs and then
> measuring them by looking at the resonant freq of the primary with the
> secondary in place.  The measured upper freq didn't match my calculations.
> Any ideas?  Forgive the lack of details in this post.  I'm keeping bandwidth
> low by putting all the details on the web page.
> 
> 
> 
> 
>