Goal

goal of this exercise. is to have fun.
another goal was to discover wether tubes could be usefully used for something.

Setup

I have a home made variable powersupply.
one side is used for fillament It's a pcf80 ran at 12V B+.
seems a bit low. but it works great!!
the Filament supply is at 16V. even though the datasheet says it should only really be 9V