The two 3-500zg's I put in my Henry 2K Classic X show little color at 1 KW
on data modes, modest color, dull red to low orange at 1.5KW mode.
The former is with 3 Kv on anode and the later is with 4 Kv on the anode and
approximately .800 current on the plate. Of course this amplifier had a
squirrel cage blower with plenmty of air going through.
The grid is showing
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