[AMRadio] Heathkit DX-60 grid current drops

[Brian - KF5CCN]

My Heathkit DX-60 grid current drops after a couple of minutes and will keep dropping more rapidly as I increase drive level. Eventually the tube plates glow red. I am tuning by the book.
Any ideas?

73                                             
Brian
KF5CCN at ARRL.NET
KF5CCN.COM
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