If the channel that's out follows the tube, I would replace the tube.
Having said that, an intermittent short caused by debris or untrimmed leads may periodically destroy any tube you plug into the SEX if it shorts things out.
In the first photo, it appears that there's a piece of metal between where the blue wire connects and where the striped end of the 1000uF/35V capacitor connects. If that is the case, you 380V power supply would short to ground through your plate choke, and that will destroy the plate choke.
« Last Edit: April 25, 2020, 06:31:59 AM by Paul Birkeland »
Paul "PB" Birkeland
Bottlehead Grunt & The Repro Man