Make sure you're insulated, the amp is unplugged, and the filter capacitors are discharged before using a tool to remove the key. Otherwise you might get a surprise if your metal tool accidentally comes into contact with the plate or screen grid pins in the tube socket!
How do you remove a tube Key?
I’ve had this issue before but it was during a DIY tweak to the amps so I could bias them by myself. The amps were both opened up by a friend and it was simple for him to do the fix.
EL 34 tubes have what I call a locator key. The plastic part down by the pins that locates the proper alignment of the tubes into the tube socket. It also covers the point where the glass tube is drawn out, providing protection to that slim glass point amongst the tube’s metal pins.
Thinking to rotate some of my tubes from one amp to the other, the tube came out but the plastic pin/key stayed in the amp. Super.
Consequently another tube couldn’t be interchanged with that spot until the plastic piece is removed.
Is there some way to remove this piece without opening up the amp and pushing it out from behind the tube socket itself?
Also, What about re-afixing the plastic thingy to the tube itself?
Don’t worry about that, or what?
BTW… as this has happened to me at least once before, is this a common thing?
Can it be overcome/avoided somehow, apart from the obvious… don’t mess with it once they are in place bit… ? Or is this just part of using EL 34 based amps?
Mucho gras'