[Amps] gs35b 144mhz

[Carey Lockhart, KC5GTT]

Hello all,

i built a yu1aw 2 meter gs-35 amplifier about 8 months ago. been working great. just recently i can here my voice coming from the cavity. also the tube seems to be glowing a much brighter blue than before. with the lights out i can not see any arcing.  the amp is running the following

plate voltage 4100 no load
plate voltage 4600 full load
plate current 1.0a full load
bias -30v
output 1450 on diawa cn801hp

any ideas would be appreciated.

Carey, kc5gtt