Is potential penetration from anode to grid greater when grid is floating?

For example when filament current is applied to an 1H4 electron tube the grid becomes negative wrt the the average value of the filament potential.


Then if we keep the grid open and connect an anode voltage of 9V the measured grid potential at the grid wires increases a few hundred millivolts and is negative.


About 10μA can flow from cathode to anode on a circuit such as the Pleiades V6 with open grid and the mic sound is big and rather nice.






See previous posts on 1H4 on the Pleiadss V6 circuit.