Posted by Mike Harris-9 on URL: http://elecraft.85.s1.nabble.com/K3-tune-mode-question-tp2989324p2995456.html
G'day,
| When using the amp on continuous duty modes like FSK or FM, the plates
| will run a nice red-orange color. This is perfectly normal, and not a
| sign of problems.
And apparently necessary to keep them de-gassed. The gettering material
needs the heat.