I'm projecting an amplifier with a GU74B. The transformer I intend to
use has all voltages; plate, screen and filament on the same core.
This means that basically all voltages will be applied as soon as the
step start relay closes. In most literature, such as The Radio
Handbook, it is very clear that plate and screen never should be
applied to such a tube before the filament is heated. Now, I have seen
quite a few builds, both home brewed and commercial, where this is
actually not put into practice, i.e. plate and screen is applied at
the same time with the filament. So, now I'm asking for some
experience with this. Will my tube break if I apply screen and plate
before the tube is heated? My option here is to get a separate
filament transformer. It's not a big deal, but I'm curious to know how
important this is!
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