NEVER DO THIS! If you apply screen voltage without plate voltage,
screen current
will go through the roof and destroy the screen!
Always ensure plate voltage is present before applying screen voltage!
73,
Victor, 4X6GP
### On a similar note, but using high mu triodes in GG, with no B+
present, but fil on, and drive applied, all hell breaks loose, with
grid current meter pegged. Like say a HV fuse that went open.
With no B+ present, and drive applied, all the electrons are attracted
to the grid. The tube now thinks the grid is the anode. And you only
require just a bit of normal drive power to peg the grid meter.
On the bigger metal GG tubes, I used a simple fast 3agc grid fuse,
wired between the negative terminal of the grid meter...and chassis.
Ideally, fast grid overcurrent protection should be used.
Fast plate current protection would also be ideal.
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