Blu light into Power tubes....any idea?

[MetalJonesy]

got a reply from Derek at Watford Valves:

"Hi Mark

Yes the blue glow is quite normal as this is the reflection of the
electron flow against the glass when the H.T is applied
regards

Derek Rocco
Watford Valves"

 

[::XeS::]

Now I think it's normal. Thanks guys
In my Savage with JJ EL34 I've never seen blu light...probably it's more noticeable in 6L6's tubes

 

[MetalJonesy]

Usually when a tube is gone, the top turns white.

YUP!!

one of my Rubys in the 6505 had a white top and wasnt glowing! thats why i swapped em out for JJs