Regulation for Filament Voltage on 833A Tubes

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Original poster: "Mccauley, Daniel H by way of Terry Fritz <teslalist-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>

I finally got my 833A VTTC up and running and I noticed that the actual
filament voltage coming from my
10V, 10A filament transformers is about 11.6 VAC.

The nominal spec for the 833A tube is 10V +/- 0.5V  (either AC or DC).

Common sense always says you should abide by the datasheet and that
exceeding this limit would either be destructive to the tube, or reduce
optimal performance.  However, I have very limited experience with vacuum
tubes so I don't know how critical
this actually is.

What are your thoughts?  Okay as is, or do I need to control this precisely
via variac???

Thanks

The Captain