Primary impedance vs. plate voltage charts?

[Dingleberry]

Hi.

Some time ago when just surfing some tube stuff I came across some old tube data charts that were showing "optimal" primary impedance for different plate voltages for different tubes.
I should have bookmarked that page...

Now I can't find those charts anywhere. I've been googling for an hour or so with every single word combination I can make up and now I give up.

It was an old scanned document as far as I can remember.
If one can point me to the right direction that would save my day.

-T

[Structo]

I just use the Duncan Tube Data Sheet Locator.

http://www.duncanamps.com/tdslpe/

Unless there is a more specific one you are thinking of.